JP7814064B2 - System, device and program - Google Patents

Description

The present invention relates to, for example, systems, devices, and programs.

Remote engine starting devices (engine starters) that remotely start the engine for the purpose of warming the engine and regulating the temperature inside the vehicle are becoming increasingly popular. These remote engine starting devices are installed in automobiles and include a relay drive circuit that controls engine start and the operation of electrical components, and a main control circuit that controls the relay drive circuit when it receives a start command signal. The start command signal is sent from a wireless remote control transmitter (portable device) held by the user.

Patent No. 3959146

In systems like engine starters, which are remotely controlled by a portable device and another communication device, with the portable device activating the functions of the other communication device, companies have traditionally used specified low-power radios with a 420 MHz frequency band, FSK (frequency shift keying) modulation, and an output of 10 mW or 1 mW for transmitting and receiving signals. The problem with such systems is that each company has a roughly uniform communication distance limit. While the communication distance varies depending on conditions, companies are competing with each other like apples to apples, with a maximum line of sight of around 4 km, and a range of several hundred meters depending on conditions. Companies have struggled to break out of this situation, and while there has been a strong desire to do so, it has been largely industry common sense and stereotypes that have prevented them from breaking away.

The object of the present invention is to provide a system that can perform remote control more reliably and is easier to use than conventional systems.

(1) For example, a system may include a first device and a second device capable of wireless communication, the wireless communication between the first device and the second device being carried by a spread spectrum system, at least one of the first device and the second device being portable by a user, and a signal transmitted by one of the devices including a signal that activates a function of the other of the first device or the second device.

In this way, users can activate device functions by remote control using wireless communication over significantly longer distances than conventional FSK methods other than spread spectrum (frequency spread) methods, far surpassing the comparative distances of other companies. According to the results of experiments conducted by the inventors, device functions can be activated over distances roughly twice as long as conventional methods. For example, with conventional FSK methods, where the distance at which wireless communication is reliably possible is 1 km, spread spectrum methods enable communication over more than twice that distance, at over 2 km.

At least one of the first device and the second device portable by the user may be any device, for example, a golf navigation system, and preferably a handheld device or remote controller (hereinafter also referred to as "remote control" for short). For example, the signal transmitted from the remote control may include a signal that activates a function of the other of the first device and the second device. At least one of the first device and the second device portable by the user may be particularly equipped with a function for inputting instructions from the user and may be configured to transmit a signal that activates a function of the other device based on the input instruction. The function for inputting instructions from the user may be any device that can input instructions, but may be a sensor that can detect user movement, etc., and may particularly be equipped with a means for inputting user instructions. At least one of the first device and the second device portable by the user may be a wearable terminal that can be attached to the body. Preferably, at least one of the first device and the second device portable by the user is a device that can be held in the hand and preferably has a function for inputting instructions by hand. Preferably, it should have a means for inputting instructions by pressing with a finger. Even more preferably, the means for inputting instructions should be configured as a switch.

The other of the first device and the second device may be any device, but for example, it may be a device that is portable by the user, preferably a device that is not portable by the user, such as a device fixed to an object, and more preferably a device installed indoors. When fixed to an object, it may be fixed to the ground, for example, and preferably fixed to a gas, electricity, or water meter. When fixed to the ground, it may be a water sprinkler, for example. When fixed to a gas, electricity, or water meter, it may be a terminal device that transmits meter reading data to a remote control. When installed indoors, it may be installed in a golf clubhouse or inside a car. When installed in a clubhouse, it may be used as digital signage, for example. When installed in a car, it may be used as an in-vehicle device, for example. Most preferably, when the first device is a portable device, the second device is fixed to another object, or when the second device is portable, the first device is fixed to another object.

The system of the present invention may be any system, but is particularly suitable for use in consumer devices and various industrial devices, and is particularly suitable for use in automotive-related devices such as the engine starter mentioned above. This allows users to remotely control various devices appropriately.

For example, in a system for use with consumer devices, one of the first device or second device that can be carried by the user can be a remote control, and the other can be a device fixed to the ground, and the signal transmitted from the remote control can include a signal that activates the function of the device.

For systems used in consumer devices, it is desirable that one of the first or second devices, which can be carried by the user, is a portable device, and the other is a transmitter fixed to a gas, electricity, or water meter, etc. The signal sent from the transmitter to the portable device should include meter reading data and a signal that causes the portable device to compile this meter reading data (a signal that activates the functions of the portable device).

In particular, it is desirable to use a wireless communication system that uses a standard called "Wi-SUN (Wireless Smart Utility Network)," which is equipped with a terminal fixed to a gas, electricity, or water meter, and collects meter reading data via wireless communication using a portable device or the like. Using the system of the present invention with Wi-SUN allows users to collect meter reading data from even more remote locations than before, minimizing the travel effort required for data collection. For example, when reading an electricity meter in a mountainous area far from roads accessible by car and accessible only by foot, a meter reader carrying a portable device is more likely to be able to collect meter reading data (hereinafter also referred to as "meter information") within the range of travel by car, thereby increasing the possibility of shortening the travel distance even if walking is required after traveling by car. In particular, it is desirable for the portable device to be portable and move around on foot, allowing instructions to be entered manually.

More preferably, this system would have the first device be a golf navigation system and the second device be a digital signage installed in the clubhouse. In particular, the signal transmitted from the golf navigation system would include a signal that activates the display and tallying functions of the digital signage. In this case, it would be possible to display the rankings of players entered into the golf navigation system during a round on the digital signage, saving the user the trouble of tallying up player results, etc.

A system for use in automobile-related equipment may, for example, be a system for use in an automobile engine starter or car security system, with the first device being a remote control and the second device being an on-board device. In particular, the signal transmitted from the remote control may include a signal that activates a function of the on-board device, and the signal transmitted from the on-board device may include a signal that activates a function of the remote control. Preferably, the signal transmitted from the remote control is transmitted based on instructions from the user.

Here, with conventional engine starters and car security devices, for example, in large apartment buildings, there were cases where the parking lot was too far from the user's room to be usable. This problem was particularly pronounced in tower apartments. Furthermore, for example, there were cases where radio waves were blocked by concrete walls, making it impossible to use the device without going out onto the balcony. However, even in such cases, with the present invention, the user can more reliably activate the function of the other device than before. For example, the engine starter or car security function can be activated more reliably than before. Therefore, for example, even in cases where the user previously had to move to a location where radio waves could reach the car in the parking lot more easily, such as a window or balcony, to activate the function of the other device, the user is more likely to be able to activate the engine starter or car security by operating it from a location indoors, such as next to the bed.

Furthermore, for example, a system for automotive-related devices equipped with the above-mentioned remote control (portable device) and in-vehicle device could be combined with a wireless communication system that collects Wi-SUN meter information, etc., so that the in-vehicle device acts as a gateway (intermediate) to transmit meter information generated in the home to the portable device. Specifically, for example, the in-vehicle device could receive information such as gas, electricity, and water meter reading data and power generation data from a solar-powered power generator installed in the home from a Wi-SUN device in Wi-SUN mode (a modulation method other than spread spectrum), and the in-vehicle device could then transfer this received information to the user's portable device (remote control) in spread spectrum mode. This would allow users to receive meter reading data and other information within a wider cycling range than the conventional walking range. For example, in conditions where conventional Wi-SUN mode (a modulation method other than spread spectrum) only had a range of about 1 km, lowering the bit rate using spread spectrum would extend the range to 6 km. An area with a diameter of 1 km from the center of a residential house is considered to be within the daily living area (walking distance), while an area with a diameter of 6 km is considered to be the local living area (if necessary, refer to Table 5 on page 6, page 32, and Table 4-3 on page 37 of the following electronic technical information (Ishihara Hiroshi, "Basic Research on Daily Living Areas (Part 2)", [online], March 2008, Nagoya Urban Center, [searched July 5, 2016], Internet <URL: http://www.nui.or.jp/user/media/document/investigation/h19/nichijo.pdf>). Furthermore, almost everything can usually be done within the local living area (biking distance) from one's home (if necessary, refer to page 11 of the following electronic technical information: Ichimura Machio, "Method for Analyzing Commercial Demand Based on Living Areas," [online], June 2006, Community Builders' Net, [searched July 5, 2016], Internet <URL: http://www.geocities.jp/non_non_net2006/p_rep/seikatukenn2.pdf>).

Preferably, the first device is fixed to an object, and the second device is portable by the user. The user carrying the second device can activate the functions of the first device at the location of the object to which the first device is fixed, without using the second device. The second device is carried by the user and moves as the user moves on foot or bicycle, with the location of the object to which the first device is fixed as a base point (e.g., the starting point of the movement). The second device returns to the base point (e.g., the original starting point as the end point after moving to a predetermined destination) when the user moves to the location of the object to which the first device is fixed. The "movement on foot or bicycle" should be a line-of-sight distance of 5 km to 20 km. For example, the base point may be the user's home, and the user may be an elderly person with dementia. Alternatively, the base point could be an automobile, with the user walking from the automobile, shopping at a shopping center, for example, starting the engine while shopping, and then returning to the automobile, which is the base point. Alternatively, the base point could be an automobile, with the user walking from the automobile to their home after returning home, and starting the automobile engine from their home the next morning before returning to the automobile. Alternatively, the base point could be a clubhouse, with the user walking around the golf course while playing, and returning to the clubhouse after playing.

Also, for example, the first device may be a single base unit installed in a nursing facility, and the second device may be a handset carried by multiple residents of the nursing facility. For example, each handset may store a different ID, and the base unit may store a correspondence between the ID stored in each handset and the name of the person carrying that handset. Each handset transmits radio waves containing ID data using a spread spectrum method at regular intervals (e.g., every minute). The base unit checks the ID data contained in the received radio waves and the RSSI (Received Signal Strength Indicator) of the received radio waves, and when the RSSI of the received radio waves falls below a set value, it displays on the base unit the approximate distance from the base unit to the handset that transmitted the radio waves, calculated based on the RSSI level, and the name of the person associated with that ID. The "RSSI setting value" can be set by previously determining the relationship between the distance between the parent unit and child unit and the RSSI value and storing this in the parent unit, so that the distance can be entered and set in the parent unit. Alternatively, "when the RSSI falls below the setting value" can be set when the RSSI level reaches that equivalent to that outside the care facility, based on the difference in RSSI measured in advance between inside and outside the facility and set in advance.

The base unit may have the function of selecting a person's name stored in advance from a list, etc., and the function of wirelessly transmitting a signal requesting a response to a slave unit with an ID corresponding to that person's name. If the received ID is its own ID and a response is requested from the base unit, the slave unit wirelessly transmits level information regarding the received electric field strength and its own ID. The base unit determines and displays the position of the slave unit (e.g., distance from the base unit) from the electric field strength level of the received ID.

Furthermore, it is preferable to provide a function for relaying wireless inquiry signals from the base unit between sub-units. For example, the base unit may be equipped with a "normal search button (search without relay)" and a "search with relay" button. When the "normal search button" is pressed, it requests a response from all sub-units within the range of the base unit's radio waves, including their IDs and field strength levels. On the other hand, when the "search with relay" button is pressed, it requests a response from all sub-units within the range of the base unit's radio waves and from all sub-units within the range of those sub-units. The responses (e.g., the IDs and field strength levels of other sub-units) are relayed by the sub-units between the base unit and the other sub-units. Note that further relaying between sub-units may be performed, and it is preferable to set a limit on the number of relays between sub-units. Furthermore, the base unit and sub-units may each be equipped with a location detector such as a GPS, so that only sub-units within a range specified by the base unit from the base unit's location will be relayed.

Communications using the "spread spectrum method" can involve, for example, modulating the signal to be transmitted, spreading the modulated narrowband signal to a wideband using a specified spreading method, thereby reducing the power density, and then transmitting the signal from the transmitting side. On the receiving side, the received signal can be despread to obtain the original narrowband signal with higher power density. Furthermore, the "spread spectrum method" can be particularly configured to restore the original narrowband signal with higher power density by despreading, even if the spread signal received on the receiving side is a weak signal below the so-called noise floor, and then demodulate the restored original narrowband signal to reproduce it as the signal that was intended to be transmitted. In this way, it is possible to receive signals that have attenuated below the noise floor over long distances.

In addition, in communications using the "spread spectrum method," modulation of the spread signal on the transmitting side and demodulation of the spread signal on the receiving side can be performed using hardware modulators and demodulators, or by software defined radio. In particular, it is preferable to use an IC chip that performs the calculations equivalent to such modulation and demodulation.

Any communication method may be used as the "spread spectrum method," but it is particularly preferable to use a method that increases communication distance even at the expense of communication speed. For example, a frequency hopping method is preferable. It is preferable to use a method other than a direct sequence spread spread method. More preferably, the "spread spectrum method" is a method that generates a chirp signal by continuously changing the frequency, and this spreads and modulates a signal based on the data to be transmitted (hereinafter referred to as the "chirp method"). It is particularly preferable to combine the chirp method with other methods. For example, it is preferable to combine the chirp method with at least one of a frequency hopping method and a direct sequence spread spread method. Furthermore, it is most preferable to use the LoRa method, which will be described in detail later, as the "spread spectrum method." Conversely, conventional modulation methods other than spread spectrum include the above-mentioned FSK method, as well as OOK (on-off keying), GFSK (phase-continuous FSK), MSK (minimum shift keying), and GMSK (Gaussian minimum shift keying) (hereinafter, these modulation methods will be collectively referred to as "FSK, etc.").

Furthermore, "at least one of the first device and the second device" that is "portable by the user" may be any device, but may be, for example, a mobile communication device, a mobile information device, a wearable terminal, etc. Furthermore, "at least one of the first device and the second device" that is "portable by the user" may be, for example, a non-dedicated device that can perform functions other than remote control, but may particularly be a dedicated device for remote control, such as a remote control.

The "signal transmitted by the one device" may include a signal that activates a function of the other of the first device or the second device. For example, in the case of an engine starter or car security, the signal may include a signal to start the device, a signal to stop the device, a signal to change settings, etc. In the case of an engine starter or car security, the signal may include a signal to activate an alarm function from the device to a portable device or remote control. Preferably, the "signal transmitted by the one device" may include a signal other than a signal that activates a function of the other device. For example, the "signal other than a signal that activates a function of the other device" may be data detected by a sensor installed in the vehicle, such as the current cabin temperature in the case of an engine starter, or the degree of impact to the vehicle in the case of a car security.

In addition, the "signal transmitted by the one device" may be configured to include start and stop signals for consumer devices such as water sprinklers and various industrial devices. In addition, in devices such as golf navigation systems, the "signal transmitted by the one device" may be configured to include signals such as player performance information entered into the golf navigation system. Furthermore, when the system of the present invention is used in devices such as gas, electricity, or water meters that use standards such as Wi-SUN, the "signal transmitted by the one device" may be configured to include various data such as meter reading data.

For example, if the first device is a portable device such as a remote control and the second device is an in-vehicle device, the portable device may be configured to use the single receive mode and the in-vehicle device to use the continuous receive mode. This configuration extends the battery life of the portable device and allows the in-vehicle device to more reliably capture signals transmitted from the portable device. In this configuration, it is desirable for the in-vehicle device to transmit the same information multiple times. This reduces the occurrence of missed readings due to external disturbances in the portable device. Even more desirable is a function to send a signal from the in-vehicle device to the portable device indicating that it should switch to continuous receive mode, and when the portable device receives this signal, it operates in continuous receive mode. In such a configuration, it is particularly advantageous to set the time for operation in continuous receive mode to a fixed period of time. This type of communication mode can be implemented, for example, by using the communications chip "SX1272," which will be described later.

The "Single receive mode" is, for example, a mode in which only one packet is received within a set time. In particular, when communicating at a fixed reception timing, it is recommended that the receiving circuit be configured to turn on only at the required reception timing. This makes it possible to reduce power consumption during reception standby. The "Continuous receive mode" is, for example, a mode in which signals are received continuously.

(2) The wireless communication between the first device and the second device using a spread spectrum method may be a LoRa method.

This allows users to break away from the current situation where the distance at which remote control is possible is generally uniform.

A wireless system using a spread spectrum method, particularly a LoRa method (hereinafter also referred to as a "LoRa wireless system"), can communicate at a higher transmission bit rate (hereinafter simply referred to as "bit rate", "data rate" or "transmission speed") when designed for the same communication distance as an FSK method, for example. A higher bit rate shortens communication time, allowing the user to obtain a system that can quickly activate the function of one of the first and second devices when transmitting a signal to activate the function of the other device from either the first or second device.

In particular, it is preferable that at least one of the first device and the second device, which are portable by the user, has a function for inputting instructions from the user and transmits a signal to activate the function of the other device based on the input instruction. With this configuration, it is possible to obtain a system that responds quickly to input instructions.

It is desirable to set the bit rate low in the LoRa system. This allows for higher sensitivity. Most desirably, the bit rate should be set to the lowest possible setting. In particular, the bit rate of either the first or second device, whichever is more portable, should be set to the lowest possible setting. This allows the user to transmit a signal from the portable device to activate a function on the other device, thereby activating the function on the other device, from a greater distance than before. It is also desirable to set the bit rate of the portable device lower than the bit rate of the device whose function is activated by the signal transmitted from the portable device. Furthermore, it is desirable to have the configurations (3) and (3-1) described below. According to the inventors' experimental results, this configuration achieves a transmission distance approximately four times longer and a coverage area approximately 16 times larger than that of the conventional 420 MHz band FSK system.

It is desirable to set the bit rate low in this way, especially in systems that transmit and receive small amounts of digital information. It is even more desirable to set the bit rate low when transmitting digital information such as for automobile engine starters and car security systems.

LoRa wireless communication can be implemented using, for example, the SEMTECH SX1272 communications chip. This communications chip performs the modulation and demodulation of the above-mentioned signals through arithmetic processing.

(3) The wireless communication between the first device and the second device may use a sub-gigahertz frequency channel whose bandwidth is wider than that of a channel in a frequency band below the sub-gigahertz band.

This allows users to operate device functions by remote control using wireless communication, using a smaller device than before and over longer distances than before. Radio waves generally have a shorter range in the sub-gigahertz band than in frequency bands below sub-gigahertz, but this problem of short range can be solved by using a sub-gigahertz frequency channel with a wider bandwidth than the channel bandwidth in frequency bands below sub-gigahertz. For example, it is recommended to set a sub-gigahertz frequency channel whose bandwidth is wider than the channel bandwidth in frequency bands below sub-gigahertz.

Furthermore, for example, the frequency of the oscillator for wireless communication provided in the first device and the second device may be set as in (3). In particular, for example, the setting of the frequency for wireless communication may be performed by a control unit provided in the first device and the second device, and the set frequency may be set as in (3). Preferably, the control unit is a computer, and a value corresponding to the set frequency is written to a register of the computer.

(3-1) The wireless communication between the first device and the second device should be specified low-power wireless, using the sub-gigahertz band, and using a sub-gigahertz frequency where the transmittable power is greater than the transmittable power in a frequency band below the sub-gigahertz band.

The "frequency band below the sub-gigahertz band" may be the 400 MHz band, and preferably, for example, 449.7125 to 449.8250 MHz, 449.8375 to 449.8875 MHz, or 469.4375 to 469.4875 MHz, and more preferably, for example, 426.0250 to 426.1375 MHz, 426.0375 to 426.1125 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, or 429.8125 to 429.9250 MHz. In each of these bands, the channel bandwidth may be, for example, 12.5 kHz, and in particular, in the 426.0375 to 426.1125 MHz band, it may be, for example, 25 kHz. Furthermore, in the frequency bands below the sub-gigahertz band, the transmittable power may be, for example, 1 mW in the 426.0250 to 426.1375 MHz and 426.0375 to 426.1125 MHz bands, and 10 mW in all other bands.

The "sub-gigahertz band" may be, for example, a frequency band slightly lower than 1 GHz, preferably between 800 and 950 MHz. More preferably, it is the 920 MHz band defined by Japanese regulations. Even more preferably, it is a band with a center frequency of 928.15 to 929.65 MHz, and most preferably, it is a band with a center frequency of 916.0 to 928.0 MHz. In the band with a center frequency of 928.15 to 929.65 MHz, the channel bandwidth may be, for example, 100 kHz, and in the band with a center frequency of 916.0 to 928.0 MHz, the channel bandwidth may be, for example, 200 kHz. Furthermore, channels used in the sub-gigahertz band should have a bandwidth at least four times the bandwidth of channels in frequency bands below the sub-gigahertz band. Preferably, the channel has a bandwidth of 200 kHz, which is eight times the 25 kHz bandwidth of the channel in the 426.0375 to 426.1125 MHz band. More preferably, the sub-gigahertz band has a bandwidth of 200 kHz, which is 16 times the 12.5 kHz bandwidth of the channel in the 426.0250 to 426.1375 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, or 429.8125 to 429.9250 MHz band. Furthermore, the transmittable power in the sub-gigahertz band should be, for example, 1 mW in the 916.0 to 920.4 MHz and 928.15 to 929.65 MHz bands, and 20 mW in the other bands. For channels to be used in the sub-gigahertz band, it is recommended to select a channel with a transmittable power of 20mW, which is 20 times the transmittable power of 1mW or twice the transmittable power of 10mW in frequency bands below the sub-gigahertz band.

In the 400 MHz band, which is included in the "sub-gigahertz frequency band," Japanese laws and regulations at the time of filing allocate a bandwidth of 12.5 kHz or 25 kHz per channel. Meanwhile, in the sub-gigahertz band, there is the 920 MHz band, which allocates a bandwidth of 100 kHz or 200 kHz per channel. As such, the 920 MHz band is a particularly good sub-gigahertz band, as it has a wider bandwidth per channel than the 400 MHz band, which is a sub-gigahertz frequency band. While the 400 MHz band has a narrower bandwidth per channel than the 920 MHz band, its radio waves have the advantage of reaching farther distances and being less directional and more prone to diffraction, making them easier to receive even behind distant obstacles (mountains or buildings).

The inventors have found that the "channel to be used" should be one of the following: a 200 kHz bandwidth, 200 kHz intervals, totaling 15 channels in the 920.6-923.4 MHz band; and a 400 kHz bandwidth, 200 kHz intervals, totaling 14 channels in the 920.7-923.3 MHz band. In particular, the inventors have found that the "channel to be used" should be at least one of the six channels with center frequencies of 922.4 MHz, 922.6 MHz, 922.8 MHz, 923.0 MHz, 923.2 MHz, and 923.4 MHz (all with a bandwidth of 200 kHz). It is particularly desirable to have a configuration that allows switching between some of these channels, and preferably a configuration that automatically switches to a channel that is determined to have no signal present when a busy state is detected. These channels may also be configured to use a wider bandwidth by combining multiple adjacent channels; for example, five adjacent channels of the six channels listed above may be combined to use a bandwidth of 1000 kHz.

Furthermore, a "channel" may refer to, for example, a frequency band allocated for use in communications, particularly a frequency band allocated by the laws and regulations of the country of use, and particularly a frequency band allocated by the laws and regulations of Japan.

When determining whether a channel is busy (determining whether a signal is present and therefore transmission is prohibited), the level of the spread spectrum signal is determined by, for example, CAD (Channel Acceleration and Delay Time Delay).
The CAD function may be configured to detect the presence of a spread spectrum signal at a level so low that it cannot be detected by RSSI. The busy state determination may be configured to determine whether a spread spectrum signal is busy when it is -130 dBm or higher, and whether a signal of another modulation method is busy when it is -80 dBm or higher. This allows for more accurate channel busy determination, making it possible to operate the device's functions over long distances by remote control using wireless communication.

Table 1 shows all cases where the presence of a signal is confirmed by the CAD function and RSSI and where it is not. The top row of each column indicates the Busy determination, and the bottom row indicates what type of signal may be transmitted. Table 1 shows cases where signals using modulation methods other than spread spectrum can be transmitted in the first and second devices. In Table 1, when the presence of a signal is confirmed by the CAD function, it is marked as "CAD present," and when it is not confirmed, it is marked as "CAD absent." When the presence of a signal is confirmed by RSSI, it is marked as "RSSI present," and when it is not confirmed, it is marked as "RSSI absent."

As shown in Table 1, when "RSSI present" and "CAD present" are present, the busy determination is either (A) due to the presence of both a spread spectrum signal and a signal using a modulation method other than spread spectrum, or (B) due to the presence of a relatively strong spread spectrum signal (-80 dBm or higher). Therefore, in case (A), the transmission of signals using all modulation methods is prohibited, while in case (B), the transmission of signals using modulation methods other than spread spectrum is possible. Furthermore, even in case (A), transmission is possible if the spread spectrum signal has a different bandwidth and spreading rate from the existing spread spectrum signal.

When "RSSI present" and "CAD absent" are displayed, the busy status is determined to be due to the presence of a signal using a modulation method other than spread spectrum. Since no spread spectrum signal is present, spread spectrum signals can be transmitted.

When "RSSI not present" and "CAD present", the busy status is determined to be due to the presence of a spread spectrum signal. Since there are no signals using modulation methods other than spread spectrum, it is possible to transmit signals using modulation methods other than spread spectrum. Furthermore, even if a signal uses spread spectrum, it can be transmitted as long as the bandwidth and spreading rate differ from those of the existing spread spectrum signal.

When "RSSI not present" and "CAD not present" there is no busy detection, and since there are no spread spectrum signals or signals using modulation methods other than spread spectrum, signals using all modulation methods can be transmitted.

(4) The strength of the signal transmitted from the first device or the second device may be below the noise floor.

This significantly reduces the possibility of interference with signals using modulation methods other than spread spectrum, such as FSK. Methods for keeping the signal strength below the noise floor include, for example, reducing the transmission power, or transmitting the signal at a high spreading rate that keeps the signal strength below the noise floor. While a higher spreading rate slightly reduces the transmission speed of the transmitted signal, it also has the advantage of improving communication sensitivity and extending communication distance. Therefore, this allows users to operate device functions remotely via wireless communication over longer distances than before. A "noise floor" of -80 dBm is recommended.

(5) The wireless communication between the first device and the second device using the spread spectrum method may be configured to transmit signals with the same power at one of the quarter portions of the bandwidth of the channel used from both ends of the bandwidth to the inside of the bandwidth, and at the center of the bandwidth.

This allows users to operate device functions remotely using wireless communication over longer distances than before. Such systems, which have high modulation efficiency and are capable of communication at high transmission bit rates, can be implemented using, for example, spread spectrum and LoRa systems. On the other hand, FSK systems have low modulation efficiency because the signal transmission power decreases at the high-frequency and low-frequency ends of the bandwidth and the signal extends outside the bandwidth.

Spread spectrum wireless communication between a first device and a second device preferably allows signals to be transmitted at the same power near both ends of the bandwidth of the channel being used, up to a quarter of the bandwidth inside the band, and near the center of the bandwidth. More preferably, signals should be transmitted at the same power near at least one end and near the center of the bandwidth of the channel being used. Even more preferably, signals should be transmitted at the same power across the entire bandwidth of the channel being used.

In the configuration (5), it is particularly advantageous to configure the power used to transmit signals outside the bandwidth of the channel in question to be less than a specified value. This will result in a higher modulation efficiency, as the amount of signal that extends outside the bandwidth will be less than the specified value. Given the same communication distance in a communication system, the higher the modulation efficiency, the higher the bit rate at which communication is possible.

At least one of the first device and the second device should preferably be a device whose power consumption does not change even when the transmission bit rate is changed. Increasing the transmission bit rate and shortening the communication time reduces the current consumption of the device, thereby reducing power consumption in the system. In particular, it is recommended to use a battery as the power source for the device. This can extend battery life (hereinafter also referred to as "battery lifespan"). This allows users to minimize the hassle of battery replacement, etc.

At least one of the first device and the second device may be a device whose power consumption increases when the transmission bit rate is increased. In particular, it is advisable to set the transmission bit rate so that the reduction in transmission power due to a shortened communication time exceeds the increase in power consumption caused by an increase in the transmission bit rate. In this way, overall power consumption can be reduced, and battery life can be extended.

Also, for example, a first device and a second device capable of wireless communication may be provided, and the wireless communication between the first and second devices may be configured to use a method that enables transmission at the same power in the center portion of the entire width and at one peripheral end portion, instead of or in addition to the spread spectrum method. In particular, it is desirable to configure the wireless communication between the first and second devices to use an OFDM modulation method, instead of or in addition to the spread spectrum method. In particular, it is desirable to use Wi-Fi HaLow (IEEE 820.11ah).

The wireless communication between the first device and the second device should preferably be configured to use GFSK modulation instead of, or in addition to, the spread spectrum method. Preferably, this should be at a speed of several hundred bits per second or less, as compared to GFSK modulation. Even more preferably, Sigfox should be used. However, the best method at present is the spread spectrum method, and the LoRa method (2) is particularly preferable.

In addition, wireless communication between the first device and the second device may be performed via wireless network communication, but it is preferable to perform it as one-to-one communication between the first device and the second device. For example, the communication chip "SX1272" may be configured to use a SyncWord value of, for example, 0x12, rather than the 0x34 used in LoRaWAN. Preferably, it should be configured to use a value other than 0x34 or 0x12. This reduces the possibility of interference with commercially available devices that perform wireless communication using the LoRa method.

(6) Of the first device and the second device, the one that is portable by the user may be equipped with a built-in antenna for use in the wireless communication.

This allows users to use devices with simple configurations where the antenna is not exposed to the outside, particularly portable devices with excellent portability, as portable devices. This is because a wireless system using spread spectrum technology can use an antenna with lower antenna gain when designed for the same communication distance and communication bit rate as a wireless system using FSK technology.

This effect is particularly pronounced in wireless systems using the LoRa method, as in (2). Furthermore, while common spread spectrum wireless systems (WLAN, WCDMA (registered trademark), etc.) strive to prevent interference and achieve high bit rates, the LoRa method significantly improves sensitivity by spreading low bit rate signals over a wide band using spread spectrum, consuming a large bandwidth. Therefore, by adopting the LoRa communication method, it is possible to further miniaturize the built-in antenna. This allows for a system that is unobtrusive and stress-free to use, even when the user carries the portable device in a pocket, etc.

As such, LoRa wireless systems have high communication sensitivity, allowing the use of smaller antennas with lower gain. Therefore, by adopting a LoRa wireless system, it becomes possible to use a remote control (portable device) that, despite having a built-in antenna, achieves radio wave ranges comparable to those of remote controls using conventional rod antennas, providing users with a system that allows for highly portable remote controls (portable devices).

It is preferable to have the configuration (3). It is more preferable to have the configuration (3-1). It is even more preferable to have the configurations (3) and (3-1). It is most preferable to have the configurations (2), (3) and (3-1). In this case, the advantage of having a built-in antenna is particularly great.

(7) It is preferable that the user be able to change the magnitude of the signal transmission power directly or indirectly.

This allows users to use the system with optimal transmission power depending on their environment. For example, if the distance between the first and second devices is short and the communication environment is relatively good, transmission power can be minimized by setting the transmission power low within a range that does not cause problems for signal transmission. The device that transmits the signal, either the first or second device, can use a battery as its power source. This allows users to extend battery life and reduce the frequency of battery replacements, etc. On the other hand, if users want to prioritize reliable signal transmission between the first and second devices over minimizing transmission power, they can set the transmission power higher, taking into account the expected communication distance, etc. This ensures reliable signal transmission and allows users to accurately control equipment equipped with the system of the present invention.

Here, an example of a configuration in which the user can directly change the magnitude of the signal transmission power is a configuration in which the magnitude of the transmission power of the first device or the second device is set by inputting a power value. By allowing the user to directly change the magnitude of the transmission power in this way, the user can accurately adjust the transmission power to a level that is appropriate for their own usage conditions.

A configuration that allows the user to indirectly change the magnitude of the signal transmission power may, for example, be one in which the magnitude of the transmission power of the first or second device is set using a relative numerical value or index associated with the power value. Various indices associated with the power value can be considered, such as "strong, medium, weak," or an index based on the operating mode. In particular, a configuration that allows the user to select between a "long-distance communication mode (normal mode)" and a "long-life mode" with a long battery life can be used. This allows the user to choose whether to prioritize battery life or the distance at which the device's functions can be activated by remote control using wireless communication. By allowing the user to "indirectly change the magnitude of the transmission power" in this way, the user can intuitively or intuitively adjust the output to a level of transmission power that suits their usage conditions.

The configuration "allowing the user to directly or indirectly change the magnitude of the signal transmission power" may be any configuration, and may be configured to do so via switches (e.g., dip switches) or control devices provided on the non-portable first or second device, such as an engine starter or an on-board device in a car security system, or particularly via a portable first or second device, such as a handheld device such as a remote control.

The signal transmission power level may be changed based on the operation of an operating unit provided on, for example, a remote control or other device. The operating unit may be configured, for example, as a slider, or as a slider displayed on a display screen provided on the remote control or other device.

Preferably, the portable first or second device is configured to be able to select between the above-mentioned "long-distance communication mode (normal mode)" and "long-life mode." In this way, the user can extend battery life by selecting long-life mode in areas where communication is possible in long-life mode, and when communication in long-life mode becomes impossible in areas farther away than the area where communication is possible in long-life mode, the user can switch to long-distance communication mode and activate the functions of the other device by remote control using wireless communication.

Furthermore, when setting the operating mode according to the magnitude of the signal transmission power, such as "long-distance communication mode (normal mode)" or "long-life mode," each mode may be set in multiple stages or continuously according to the magnitude of the transmission power. By adopting these methods, the user can easily and accurately adjust the magnitude of the signal transmission power.

(8) It is desirable that the user be able to change the transmission bit rate of the signal directly or indirectly.

In this way, by adjusting the transmission bit rate, the user can use the system under conditions that are optimal for their environment. For example, by setting a low transmission bit rate, the user can improve communication sensitivity while ensuring a larger communication range. Conversely, by setting a high transmission bit rate, the user can minimize communication time at the expense of communication sensitivity and communication distance, enabling agile communication operations and remote control of device functions over long distances using wireless communication.

At least one of the first device and the second device should preferably be a device whose power consumption does not change even when the transmission bit rate is changed. Increasing the transmission bit rate and shortening the communication time reduces the current consumption of the device, thereby reducing power consumption in the system, and particularly in the device that transmits the signal. It is particularly recommended to use a battery as the power source for the device. This allows the user to extend battery life and minimize the hassle of battery replacement, etc.

At least one of the first device and the second device may be a device whose power consumption increases when the transmission bit rate is increased. In particular, it is advisable to set the transmission bit rate so that the reduction in transmission power due to a shortened communication time exceeds the increase in power consumption caused by an increase in the transmission bit rate. In this way, overall power consumption can be reduced, and battery life can be extended.

Here, an example of a configuration in which the user can directly change the signal transmission bit rate is one in which the transmission bit rate of the first device or the second device is set by inputting a bit rate value. By allowing the user to directly change the magnitude of the transmission bit rate in this way, the user can accurately adjust the transmission bit rate to suit their own usage conditions.

An example of a configuration that allows the user to indirectly change the signal transmission bit rate is one in which the transmission bit rate of the first or second device is set using a relative numerical value or index associated with the transmission bit rate. Various indices associated with the transmission bit rate are possible, such as "large, medium, or small," or an index based on the operating mode. In particular, it is recommended that the user be able to select between a "normal mode" and a "speed mode" that provides fast communication. This allows the user to choose whether to prioritize the distance at which the device's functions can be activated by remote control using wireless communication, or the speed of communication. By allowing the user to indirectly change the signal transmission bit rate in this way, the user can intuitively or intuitively adjust the transmission bit rate to a level that suits their own usage conditions.

The configuration "allowing the user to directly or indirectly change the signal transmission bit rate" may be any configuration, and may be configured to be performed via switches (e.g., dip switches) or control devices provided on the non-portable first or second device, such as an engine starter or an on-board device in a car security system, or particularly via a portable first or second device, such as a handheld device such as a remote control.

Preferably, the portable first or second device is configured to be selectable between the above-mentioned "normal mode" and "speed mode." In this way, the user can select speed mode in areas where communication is possible in speed mode to make communication operations more agile. When communication in speed mode becomes impossible in areas farther away than the area where communication is possible in speed mode, the user can switch to normal mode and activate the functions of the other device by remote control using wireless communication.

The transmission bit rate may be changed, for example, by operating an operation unit on a remote control or other device. The operation unit may be configured, for example, as a slider, or as a slider displayed on a display screen on the remote control or other device.

Furthermore, when setting the operating mode according to the transmission bit rate, such as "normal mode" or "speed mode," each mode may be set in multiple stages or continuously according to the transmission bit rate. By adopting these methods, the user can easily and accurately adjust the signal transmission bit rate.

(9) In the information regarding the strength of the signal received in the last communication between the first device and the second device, if the strength of the signal is equal to or greater than a predetermined value and transmission occurs within a predetermined time from reception of the signal in the last communication, the transmission power is reduced; and if the strength of the signal is less than the predetermined value or transmission occurs after a predetermined time has elapsed from reception of the signal in the last communication, the transmission power is maintained at least at the transmission power at the time of the last communication.

This allows users to optimize transmission power consumption while ensuring reliable signal transmission and reception in the system. For example, if the signal strength received by a device in the last communication is stronger than necessary, the strength of the next transmitted signal can be reduced. Here, since at least one of the first and second devices is portable, even if the signal strength received by the device is stronger than necessary, the distance between the first and second devices may increase over time due to the user's movement, etc. In this way, when adjusting the transmission power for the next communication based on the signal strength received by the device in the last communication, it is advisable to assume, for example, a change in the distance between the first and second devices using time as an index and adjust the power based on this assumption. In the configuration (9), the transmission power is reduced not only when the signal strength received in the last communication is equal to or greater than a predetermined value, but also when the next signal is transmitted within a predetermined time since the reception of the signal in the last communication. Furthermore, in the configuration (9), the transmission power is maintained at least when the signal strength is less than a predetermined value or when transmission occurs after a predetermined time has elapsed since the reception of the signal in the last communication. This allows users to operate device functions remotely over long distances using wireless communication, while also reducing transmission power consumption. Furthermore, if a battery is used as the power source, battery life can be extended, eliminating the need for frequent battery replacement.

Here, the "predetermined time" may be set based on the estimated distance at which communication between the first and second devices would be established even if the distance between them were to increase, and the assumed speed at which the distance between the first and second devices would increase, for example, when attempting to reduce the transmission power of the next signal to be transmitted below the transmission power of the signal transmitted in the last communication. For example, assuming that one of the first and second devices is a portable device such as a remote control and the other is a stationary device, and assuming that the distance between the first and second devices increases as the user moves on foot, the "predetermined time" may be set based on the relationship between the average walking speed of an average adult, the estimated distance at which communication would be established between the first and second devices after the transmission power was reduced, and the expected reduction in communication distance due to the reduction in transmission power. In this way, by using time as an index to estimate changes in the distance between the first and second devices, setting a "predetermined time" based on this estimation, and using this predetermined time as one of the criteria for reducing transmission power, the user can operate the device's functions over long distances by remote control using wireless communication without any inconvenience, even when control is performed to reduce transmission power consumption.

The "predetermined time" for reducing transmission power may be, for example, between one and two minutes. This "predetermined time" may be constant or may vary depending on the signal strength.

In this case, it would be a good idea to configure a system in which the first device is a portable device (such as a remote control) and the second device is a fixed device (such as an in-vehicle device or a home device that receives external power). In this way, in a system in which basic control begins with sending commands from the remote control, it is possible to reduce the transmission power consumption of the fixed device. In this case, for example, if the fixed device is configured to use the car's battery as its power source, such as an engine starter or car security system, the power consumption of this battery can be minimized.

It would also be beneficial to configure a system in which the fixed device periodically transmits a link confirmation signal to the remote control. In this way, the radio wave strength of the link confirmation signal can be monitored and the transmission power of the remote control's transmission signal can be reduced. Reducing the remote control's transmission power and power consumption can extend the life of the battery built into the remote control (portable device), eliminating the need for users to frequently replace the battery.

Also, for example, if the amount of information to be transmitted is large and the information is divided into multiple transmissions, it is advisable to configure the first transmission to be performed with high transmission power, and adjust the second and subsequent transmissions based on the radio wave strength of the first transmission. This allows for optimization of transmission power. In this case, it is advisable to configure the device to use a battery as the power source, for example. This can extend battery life and minimize the frequency with which users need to change batteries.

Also, for example, in the case of car security, when a sensor detects that some kind of trouble has occurred in the car, a signal can be sent from the in-vehicle device, which is a fixed device, to the remote control, even if no command is sent from the remote control. In this way, when a user who has learned that the car security is activated operates the remote control to disable the car security, the transmission power of the remote control's transmission signal can be reduced based on the radio wave strength of the signal previously received from the in-vehicle device, minimizing power consumption in the remote control's built-in battery and minimizing the frequency with which the user has to replace the battery.

Furthermore, it is desirable to configure the system so that signals can be sent to the fixed device using, for example, a remote control. In this way, the remote control can send a setup start command, and based on the radio wave strength of the response signal returned from the fixed device, the transmission power of the signal from the remote control can be reduced, minimizing power consumption in the remote control's built-in battery and minimizing the frequency with which the user needs to replace the battery.

A user carrying a remote control may move after receiving a signal in the system's last communication. Therefore, if the transmission power of the remote control or fixed device is reduced after a predetermined time has elapsed, the distance between the remote control and the fixed device may become too great, resulting in insufficient radio wave strength and making it impossible to activate device functions via remote control using wireless communication over long distances. Therefore, it is recommended that the transmission power be reduced within a predetermined time and that the transmission power be maintained after the predetermined time has elapsed. This allows device functions to be activated via remote control using wireless communication over long distances, while also extending battery life. This minimizes the frequency with which users have to perform tedious tasks such as battery replacement.

Furthermore, the configuration for "maintaining at least the transmission power" may be a configuration for maintaining the transmission power, or a configuration for increasing the transmission power. As in the configuration (9), when the strength of the signal received in the last communication is below a predetermined value or when transmission is performed after a predetermined time has elapsed since the signal was received in the last communication, it is preferable to maintain the transmission power at least at the transmission power level at the time of the last communication. This prevents communication from being terminated due to a reduction in transmission power, ensuring communication stability. This allows the user to operate the device's functions by remote control using wireless communication over long distances without any inconvenience, even when the strength of the signal received in the last communication was weak or a predetermined time has elapsed since the previous communication.

If the "predetermined time" for reducing transmission power is changed depending on the signal strength, it is recommended that the greater the signal strength, the shorter the predetermined time, and the weaker the signal strength, the longer the predetermined time. However, if the signal strength is below the predetermined value, the transmission power should at least be maintained.

In the configuration of (9), for example, if communication is not possible with the transmission power lowered, the transmission power is increased, and if communication is still not possible, the transmission power is increased further. When communication is not possible with the transmission power lowered, the transmission power is increased in stages or continuously, and in particular, it is preferably increased directly to the maximum. This provides the user with the benefit of being able to minimize power consumption.

In the configuration (9), for example, the transmission power settings of the remote control and fixed device may be set to maximum under normal conditions and then automatically reduced, or the user may set it by operating the remote control or by setting a dip switch on the vehicle-mounted device. The remote control's display screen may also be able to display the transmission power. This allows the user to check the transmission power. The remote control's display screen may also be able to display the strength of the received radio waves. This allows the user to use the remote control while checking whether communication is possible based on the displayed radio wave strength.

(10) In the information regarding the strength of the signal received in the last communication between the first device and the second device, if the strength of the signal is equal to or greater than a predetermined value and the signal is transmitted within a predetermined time from the reception of the signal in the last communication, the transmission bit rate for transmitting the signal may be increased; and if the strength of the signal is less than the predetermined value or the signal is transmitted after a predetermined time has elapsed from the reception of the signal in the last communication, the transmission bit rate may be maintained at least at the transmission bit rate at the time of the last communication.

This allows the user to optimize the transmission bit rate while ensuring reliable signal transmission and reception in the system. For example, if the signal strength received by a device in the last communication is greater than necessary, the strength of the next signal transmitted can be reduced. Here, since at least one of the first and second devices is portable, even if the signal strength received by the device is greater than necessary, the distance between the first and second devices may increase over time due to the user's movement, etc. In this way, when adjusting the transmission bit rate for the next communication based on the signal strength received by the device in the last communication, it is advisable to assume, for example, a change in the distance between the first and second devices using time as an index and adjust the rate based on this assumption. In the configuration (10), the transmission bit rate is increased not only when the signal strength received in the last communication is greater than a predetermined value, but also when the next signal is transmitted within a predetermined time from the reception of the signal in the last communication. Furthermore, in configuration (10), the transmission bit rate is maintained at least when the signal strength is below a predetermined value or when a predetermined time has elapsed since the last signal was received. This allows the user to operate the device's functions remotely over long distances using wireless communication, while also reducing transmission power consumption. Furthermore, if a battery is used as the power source, the battery life can be extended, eliminating the need for frequent battery replacement by the user.

Here, the "predetermined time" may be set based on the estimated distance over which communication between the first and second devices would be established even if the distance between them were to increase, for example, compared to the transmission bit rate at the time of the last communication. The "predetermined time" may be set based on the estimated distance over which communication would be established between the first and second devices even if the distance between them were to increase, and the estimated speed at which the distance between the first and second devices would increase. For example, if one of the first and second devices is a portable device such as a remote control and the other is a stationary device, and the distance between the first and second devices increases as the user moves on foot, the "predetermined time" may be set based on the average walking speed of an average adult, the estimated distance over which communication would be established between the first and second devices after the increase in the transmission bit rate is reduced, and the expected reduction in communication distance due to the increase in the transmission bit rate. In this way, by using time as an index to estimate changes in the distance between the first and second devices, setting a "predetermined time" based on this estimated result, and using this predetermined time as one of the criteria for increasing the transmission bit rate, the user can operate the device's functions by remote control using wireless communication over long distances without feeling any inconvenience, even when control is performed to increase the transmission bit rate.

The "predetermined time" for increasing the transmission bit rate may be, for example, between one and two minutes. This "predetermined time" may be constant or may vary depending on the signal strength.

Furthermore, the configuration for "maintaining at least the transmission bit rate" may be a configuration for maintaining the transmission bit rate, or a configuration for lowering the transmission bit rate. As in the configuration (10), when the strength of the signal received in the last communication is below a predetermined value or when transmission is performed after a predetermined time has elapsed since the signal was received in the last communication, it is preferable to maintain the transmission bit rate at least at the transmission bit rate at the time of the last communication. This prevents communication from being terminated by increasing the transmission bit rate, ensuring communication stability. This allows the user to operate the device's functions by remote control using wireless communication over long distances without any inconvenience, even when the strength of the signal received in the last communication was weak or a predetermined time has elapsed since the previous communication.

For a given bandwidth in a communications system, the transmission bit rate, sensitivity (travel distance), and transmission power are inversely proportional to each other. In other words, in the system of the present invention, increasing the transmission bit rate reduces the distance (decreased sensitivity) for the same bandwidth and transmission power, shortening the distance at which device functions can be activated by remote control using wireless communication. However, this shortens the transmission time and enables faster system communication. Here, if the received signal strength is high, communication is possible even with low sensitivity, and therefore communication is possible even if the transmission bit rate is increased. Therefore, in configuration (10), it is advisable to increase the transmission bit rate the stronger the received radio waves. In this way, a user can obtain a system that allows them to quickly activate a function from either the first or second device when transmitting a signal to activate the other device's function.

(11) In the wireless communication using the spread spectrum method, it is preferable that multiple spreading rates be set, and that the spreading rate be changed when predetermined conditions are met.

In this way, users can create a wireless system that is extremely difficult to intercept.

The "changing of the spreading factor" may be configured to be performed in a predetermined pattern. The "predetermined pattern" of the "changing of the spreading factor" may be configured to be random or in a predetermined order. Here, in the system of the present invention, the higher the spreading factor, the longer the distance at which the device's functions can be activated by remote control using wireless communication. Therefore, it is particularly preferable to configure the system to use the maximum spreading factor and the spreading factor one level lower. In such a configuration, the pattern for changing the spreading factor may be configured to alternate between the maximum spreading factor and the spreading factor one level lower in a predetermined pattern. In this way, it becomes possible to activate the device's functions by remote control using wireless communication over a long distance and in a manner that is difficult to intercept.

"When a specified condition is met" may be configured to occur every time one packet is sent, every time a packet with a specified amount of data is sent, or every time a specified amount of time has passed.

The "spreading factor" may be, for example, the ratio (C/B) of the spreading code speed (also called the "chip rate"; C) to the transmission bit rate (B).

(12) It would be good to be able to communicate by switching the channel used for communication.

By doing this, communication is carried out while the frequency band allocated for use in communication is switched, allowing users to obtain a system that is less susceptible to interference between spread spectrum communication systems. In this case, the receiving and transmitting sides switch channels in sync. For example, if the band used for wireless communication is the 920 MHz band, it would be desirable to configure the system to switch between six channels with center frequencies of 922.4 MHz, 922.6 MHz, 922.8 MHz, 923.0 MHz, 923.2 MHz, and 923.4 MHz. However, channels other than these may also be used.

Spread spectrum systems, particularly LoRa systems, allow for significantly longer communication distances than FSK systems. Therefore, when using a communication system with a long communication distance, such as LoRa systems, there is a high possibility of interference occurring due to other users' communications interrupting the communication range. Therefore, when using spread spectrum systems, particularly LoRa systems, it is preferable to suppress interference by appropriately switching the channel used for communication. This allows users to communicate stably without being affected by other users' devices that use spread spectrum communication nearby.

(13) A system according to any one of (1) to (12), comprising a vehicle control device that starts a vehicle drive device based on a predetermined vehicle start signal, and a start permission device capable of transmitting a start permission signal to the vehicle control device that permits the drive device to be started, the system receiving the PIN code transmitted from a PIN code transmitter that is portable by a user and capable of transmitting a predetermined PIN code, and indirectly transmitting the PIN code to a vehicle to which the start permission signal is transmitted by the start permission device based on the received PIN code and a reference code provided in the start permission device, wherein the system is configured to: The wireless communication with the first device can be selected between a spread spectrum method and a communication method other than the spread spectrum method, the first device can be carried by a user, can receive the PIN code from the PIN code transmitter, and can transmit to the second device a signal including a conversion code obtained by converting the received PIN code using a predetermined method, and a start instruction signal, and the second device can be mounted on the vehicle, can convert the received conversion code into the PIN code, transmit the converted PIN code to the start permission device, and can transmit the vehicle start signal to the vehicle control device upon receiving the start instruction signal.

In this way, in a vehicle equipped with a PIN-code-based start permission device (known as an immobilizer), for example, a user can start a drive device such as an engine or motor using a remote control (a first device that can be carried by the user) without having to leave the PIN code transmitter inside the vehicle, but instead carrying it with them. Generally, due to security concerns, for example, the PIN code transmitter and the start permission device must be in close proximity to send and receive the PIN code, and the drive device cannot be allowed to start. However, in this way, even if the PIN code transmitter and the start permission device are far apart, the PIN code transmitted from the PIN code transmitter is relayed between the remote control (a first device that can be carried by the user) and the on-board device (a second device mounted on the vehicle), and can be received by the start permission device, allowing the drive device to start.

An example of a configuration for "indirectly transmitting" a PIN code is one in which a first device receives the PIN code from a PIN code transmitter, converts the PIN code into a different conversion code, and transmits it to a second device, and the second device then converts the received conversion code back into the original PIN code before transmitting it to the start permission device.

With regard to the second device, "mounted on a vehicle" preferably refers to a configuration in which the device is originally attached to the vehicle by the automobile manufacturer when the vehicle is manufactured, and in particular, a configuration in which the device is retrofitted to a vehicle that has already been sold.

The start instruction signal transmitted by the first device may be configured to be issued in response to a user instruction.

The wireless communication between the first device and the second device may be configured to select between a spread spectrum method and a communication method other than the spread spectrum method. This increases the likelihood that the drive device will be permitted to start even if it is difficult to permit starting using one of the methods. The "communication method selection" may be configured in any way, such as via switches (e.g., dip switches) or a control device provided on the vehicle-mounted device (the second device mounted on the vehicle), and particularly via a remote control (the portable first device). The communication method may also be selected based on the operation of an operating unit provided on the remote control or another device. The operating unit may be configured, for example, as a slider, or as a slider displayed on a display screen provided on the remote control or another device.

It is desirable to configure the system so that the user can select between a mode in which the PIN code transmitted from the PIN code transmitter is relayed between a first communication device carried by the user and a second communication device installed in the vehicle (hereinafter referred to as "relay mode"), and a mode in which the PIN code is not relayed (hereinafter referred to as "non-relay mode"). In this way, users and retailers can support both vehicle models with immobilizers and vehicle models without immobilizers by simply preparing one type of system equipped with a remote control and an onboard device, and can also accommodate users of vehicles with immobilizers who are willing to leave the PIN code transmitter in their vehicle. The selection between "relay mode" and "non-relay mode" can be made by providing a selection means such as a switch on the onboard device, for example, and using this selection means.

When "Relay Mode" is selected, it is recommended that wireless communication be configured as a continuous mode using a communication method other than spread spectrum. In this case, the "communication method other than spread spectrum" should be FSK or similar. "Continuous Mode" is a mode in which the DIO2/DATA pin level is transmitted as is (without going through a FIFO).

When the "non-relay mode" is selected, it is preferable to select either the "long distance mode" or the "short distance mode." The "long distance mode" is preferable to select a packet mode of the spread spectrum method for wireless communication, and in particular, a packet mode of the LoRa method. The "packet mode" is preferable to select a packet mode of the SPI (Serial Peripheral
It is preferable to configure the device so that data provided by the FIFO interface is sent as packets via a FIFO.

The "short-distance mode" may be configured so that wireless communication is in packet mode using a communication method other than spread spectrum, and preferably so that wireless communication is in packet mode using spread spectrum with a higher transmission bit rate than in long-distance communication mode, and even more preferably so that wireless communication is in LoRa mode with a higher transmission bit rate than in long-distance communication mode. A communication device that can select between LoRa and FSK, and between continuous mode and packet mode, may be, for example, the above-mentioned communication chip "SX1272."

Any of the configurations (1) to (13) may be arbitrarily combined. Furthermore, any of the components described in the configurations (1) to (13) may be arbitrarily combined.

(14) For example, it may be configured as the first device in any of the systems described in (1) to (13) above.

(15) For example, it may be configured as a second device in any of the systems described in (1) to (13) above.

Such devices may be, for example, devices for systems used in the above-mentioned consumer devices and various industrial devices, or devices for wireless communication systems that collect meter reading data, and may particularly be configured as devices for systems used in automobile-related equipment. Devices for systems used in automobile-related equipment may be configured as remote controls or in-vehicle devices, for example, as devices for systems used in engine starters.

(16) For example, it may be configured as a program for causing a computer to implement the functions described in any of (1) to (13) above.

The present invention makes it possible to provide a system that allows for more reliable remote control and is easier to use than conventional systems.

FIG. 1 is a block diagram showing an outline of an example of the configuration of an engine starter using a system according to the present invention. FIG. 2 is an external view of an engine starter using the system according to the present invention, where FIG. 2(a) is a front view of the remote control, and FIG. 2(b) is a perspective view of the junction unit. FIG. 3 shows the display on the display unit of the remote controller and the sound emitted from the remote controller when starting the engine using the remote controller. FIG. 4 shows the display on the display unit of the remote controller and the sound emitted from the remote controller when checking the engine status using the remote controller. FIG. 5 shows the display of the remote controller and the sound emitted from the remote controller when idling extension is performed using the remote controller. FIG. 6 shows the display on the display unit of the remote controller and the sound emitted from the remote controller when the engine is stopped using the remote controller. FIG. 7 shows the display on the display unit of the remote control and the sound emitted from the remote control when the door is locked or unlocked using the remote control. FIG. 8 is an explanatory diagram of the first remote control registration method. FIG. 9 is an explanatory diagram of the second remote control registration method. FIG. 10 is a block diagram showing an outline of another example of the configuration of an engine starter using the system according to the present invention, and shows the case where the user carries and uses the original key in a car equipped with an immobilizer. FIG. 11 is a block diagram showing an outline of another example of the configuration of an engine starter using the system according to the present invention, and shows the case where the original key is placed inside a car equipped with an immobilizer. FIG. 12 is a block diagram showing an outline of another example of the configuration of an engine starter using the system according to the present invention, in which the system is used in an automobile not equipped with an immobilizer.

A preferred embodiment of the present invention will now be described with reference to the accompanying drawings. The system of this embodiment is a system used in an engine starter that starts an automobile engine (drive unit) by remote control using a remote controller (hereinafter referred to as "remote control"). Note that the present invention is not limited to the examples shown in the embodiments described below, and it will be readily apparent to those skilled in the art that other embodiments may be possible within the scope of the claims and within the spirit and teachings of the present invention.

1. Configuration of engine starter Fig. 1 is a block diagram showing an outline of an example of the configuration of an engine starter using the system according to the present invention. Fig. 2 is an external view of the engine starter using the system according to the present invention, in which Fig. 2(a) is a front view of the remote control and Fig. 2(b) is a perspective view of the junction unit.

As shown in FIG. 1, the engine starter 10 includes a remote control 20 (first device) and a junction unit 40 (second device) mounted on the vehicle. The remote control 20 can be held by the user for operation and transportation. As shown in FIG. 2(a), the remote control 20 includes a display unit 24 on the front of a flat, approximately rectangular case 22 with rounded top and bottom edges, extending from the center to the top in the vertical direction. The display unit 24 is a monochrome, two-tone segmented LCD screen. The display unit 24 incorporates a seven-color backlight, which illuminates when an operation of the operation button 26 is detected, improving visibility. However, because leaving the backlight on constantly consumes battery power quickly, the backlight is turned on for a set period of time and then turned off. This period can be changed by the user (e.g., 5 seconds, 10 seconds, or 20 seconds (default setting is 5 seconds)). A completely dark mode is also available. The backlight color can also be changed by the user (for example, white/yellow/purple/blue/orange/green/indigo). The display unit 24 displays the setting items and details during setup, and can display the operating status of the system and engine during use. Figures 3 to 8, described below, show examples of various displays on the display unit 24.

Operation buttons 26 are provided below the display unit 24 on the front of the case 22. The operation buttons 26 are used for operation and include a start button 26a, an engine button 26b, and a stop button 26c. The start button 26a also functions as a lock button, and the stop button 26c also functions as an unlock button. As shown in FIG. 2(a), the start button 26a on the left side and the stop button 26c on the right side are adjacent to each other, and the engine button 26b is located below the start button 26a and the stop button 26c. A rod-type antenna 28 is provided on the upper left of the case 22. The antenna 28 is pulled out fully when the remote control 20 is in use and pushed in fully when not in use. A battery cover (not shown) is provided on the back of the case 22.

The remote control 20 includes a wireless communication circuit 30, a control unit 32, and a battery 34 inside the case 22, as shown in Figure 1.

The junction unit 40 is installed in the vehicle after purchase. As shown in Figure 2(b), the junction unit 40 includes a first connector 42 that connects via cables to the vehicle's key cylinder connector and vehicle connector, a second connector 44 that connects via cables to the brake detection line, door lock line, door unlock line, etc., a third connector 46 that connects to the temperature sensor 54, and a fourth connector 48 that connects to the antenna unit 56.

The first connector 42, the key cylinder connector, and the vehicle connector are connected so that when the remote control 20 is operated, the same signal that is sent from the key cylinder via the cable to the vehicle when the key cylinder is operated with a key is sent from the junction unit 40 to the vehicle via the first connector 42 and the cable. Therefore, for example, when the remote control 20 is used to start the engine, the same vehicle start signal that is sent when the car's engine is started with the key is sent to the vehicle control device on the vehicle side, and the engine starts.

The door lock and door unlock lines connected to the second connector 44 are connected to a door control device on the vehicle side. When the door is locked or unlocked using the remote control 20, the same door lock or door unlock signal that is sent to the door control device when the door is locked or unlocked using the key or a remote control originally attached to the key (a remote control separate from the remote control 20) is sent from the junction unit 40 to the door control device, locking or unlocking the door.

Note that each remote control 20 is assigned a unique ID, and when the junction unit 40 receives a signal from a remote control 20 whose ID is paired with that junction unit 40, it operates based on that signal. Therefore, for example, even if an operation to start the engine is performed using an unpaired remote control 20, the junction unit 40 will not respond to the vehicle start signal sent from that remote control 20, and the engine will not be able to start.

The junction unit 40 internally includes the wireless communication circuit 50 and control unit 52 shown in Figure 1. The junction unit 40 is powered by the vehicle's battery.

The remote control 20 and junction unit 40 both include the SEMTECH SX1272 communications chip, and the wireless communication circuit 30 of the remote control 20 and the wireless communication circuit 50 of the junction unit 40 are both built around this communications chip. The wireless communication circuit 30 of the remote control 20 is connected to the antenna 28, and the wireless communication circuit 50 of the junction unit 40 is connected to the antenna unit 56.

The wireless communication circuits 30 and 50 can switch between six channels, CH33 to CH38, in the 920 MHz sub-gigahertz band. The center frequencies of the channels are 922.4 MHz for CH33, 922.6 MHz for CH34, 922.8 MHz for CH35, 923.0 MHz for CH36, 923.2 MHz for CH37, and 923.4 MHz for CH38. Each channel has a bandwidth of 200 kHz and a transmittable power of 20 mW. Wireless communication between the remote control 20 and junction unit 40 is specified low-power radio.

The 200 kHz bandwidth of these channels is 16 times the 12.5 kHz bandwidth of the channels in the bands 426.0250 to 426.1375 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, or 429.8125 to 429.9250 MHz used in conventional engine starters. Furthermore, the 20mW transmittable power for these channels is 20 times the 1mW transmittable power for 426.0250-426.1375MHz or 426.0375-426.1125MHz used in conventional engine starters, and twice the 10mW transmittable power for 429.1750-429.2375MHz, 429.2500-429.7375MHz, or 429.8125-429.9250MHz.

Wireless communication between the remote control 20 and junction unit 40 is carried out by the wireless communication circuit 30 and the wireless communication circuit 50. Radio waves used for wireless communication between the remote control 20 and junction unit 40 are transmitted and received via the antenna 28 of the remote control 20 and the antenna unit 56 of the junction unit 40. Wireless communication between the remote control 20 and junction unit 40 is carried out using the LoRa method, a spread spectrum method. Furthermore, wireless communication between the remote control 20 and junction unit 40 transmits signals at the same power in one of the quarter portions of the bandwidth from both ends of the bandwidth of the channel used, and at the center of the bandwidth.

The control unit 32 of the remote control 20 and the control unit 52 of the junction unit 40 each comprise a microcomputer equipped with a CPU, ROM, RAM, flash memory, various peripheral circuits, interfaces, etc. The control units 32 and 52 use a boot loader stored in ROM to expand the OS and application programs stored in the flash memory onto RAM, and execute the OS and application programs in RAM to perform various processes and realize various functions. Unless otherwise noted, all functions are realized by the processing of the control units 32 and 52. The frequency or channel of the oscillators used for wireless communication provided in the wireless communication circuit 30 of the remote control 20 and the wireless communication circuit 50 of the junction unit 40 is written to a register in the microcomputers provided in the control units 32 and 52.

2. How to Use and Operation of the Engine Starter Next, how to use and operation of the engine starter 10 will be described.

2-1. Starting the Engine Figure 3 shows the display on the display unit of the remote control and the sound emitted from the remote control when starting the engine using the remote control. (a) to (i) in the following explanation correspond to (a) to (i) in the figure, respectively.

(a) To start the car engine, press the engine button 26b until the remote control 20 emits a beep to confirm operation. The display unit 24 will show a flashing "E."

(b) Next, while "E" is flashing (for approximately 3 seconds), press the start button 26a until the remote control 20 emits the "Do Re Mi Fa So" sound. The display 24 displays "START" along with a transmission animation, and a start instruction signal is sent from the remote control 20. When the junction unit 40 recognizes the start instruction signal, it sends a response signal back to the remote control 20. As shown in (b1), the transmission animation shows three horizontal lines lined up one above the other moving from right to left in order from the top, followed by two vertical lines moving from right to left, repeating this action.

(c) While waiting for a response signal from the junction unit 40, the backlight on the display unit 24 slowly flashes and a reception waiting animation is displayed in which horizontal bars 24a light up sequentially from left to right.

(d) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits a receiving sound "So-Fa-Mi-Re-Do." Here, if the cabin temperature display setting is ON, the current cabin temperature is displayed on the display unit 24 for a certain period of time based on the temperature information contained in the response signal, after which the temperature display disappears and the system waits for reception of an engine start confirmation signal. The temperature information is the cabin temperature detected by the temperature sensor 54.

(e) On the other hand, when the cabin temperature display setting is OFF, when the remote control 20 emits the receiving sound "Sofa Mire Do," the display unit 24 displays "OK" for a certain period of time, then the OK display disappears and the system waits for reception of an engine start confirmation signal.

The junction unit 40 sends a vehicle start signal to the vehicle control device to start the engine. When the engine starts, the junction unit 40 detects the engine start and sends an engine start confirmation signal to the remote control 20. The vehicle start signal sent by the junction unit 40 is the same as the vehicle start signal sent from the key cylinder when an operation to start the engine is performed using a key.

(f) When the remote control 20 receives an engine start confirmation signal transmitted from the junction unit 40, the remote control 20 emits the reception sound "Do Re Mi Fa So Fa Mi Re Do." Here, if auto-stop is disabled, the display unit 24 displays the engine start animation 24b and the idling setting time.

(g) On the other hand, when auto-stop is enabled, when the remote control 20 emits the received sound "Do Re Mi Fa So Fa Mi Re Do," the display unit 24 displays the engine start animation 24b and "AUTO." Auto-stop is a function that automatically stops idling if the interior temperature reaches a preset temperature while idling, in order to prevent unnecessary idling of the vehicle. If the interior temperature at the time of engine start is within ±2°C of the set temperature, the idling time is fixed to 5 minutes.

When idling, the junction unit 40 emits a series of beeps to notify you that the vehicle is idling.

If the junction unit 40 is unable to detect engine start, it will attempt to restart (retry) twice.

(h) When a retry operation is performed, "RT" will flash on the display unit 24 to notify the user of the retry operation.

(i) If the engine does not start even after the second retry operation, a retry failure signal is sent from the junction unit 40, and the remote control 20 that receives the retry failure signal emits a "beep beep beep" sound, the display unit 24 flashes "ER", and the retry operation is stopped. Even if the retry setting is turned OFF, the display unit 24 will show the same message as in (i).

2-2. Checking the engine status Figure 4 shows the display on the display unit of the remote control and the sound emitted from the remote control when checking the engine status using the remote control. (a) to (i) in the following explanation correspond to (a) to (i) in the figure, respectively.

(a) To check the engine status, press the engine button 26b until the remote control 20 emits a beep to confirm operation. The display unit 24 will show a flashing "E."

(b) Next, while "E" is flashing (for approximately 3 seconds), press the engine button 26b again until the "Do-Re-Mi-Fa-So" sound is emitted from the remote control 20. "chK" will be displayed on the display unit 24.

(c) "chK" is displayed on the display unit 24 followed by a transmission animation, and an engine status confirmation signal is transmitted from the remote control 20. When the junction unit 40 recognizes the engine status confirmation signal, it transmits a response signal back to the remote control 20.

(d) While waiting for a response signal from the junction unit 40, the backlight on the display unit 24 slowly flashes and a reception waiting animation is displayed in which the horizontal bars 24a light up in sequence from left to right. If the engine fails to start, a start error sound can be heard by pressing the engine button 26b twice.

(e) Here, when the cabin temperature display setting is ON, the remote control 20 emits the receiving sound "Sofa Mire Do," and the cabin temperature is displayed on the display unit 24 based on the temperature information contained in the response signal. The temperature information is the cabin temperature detected by the temperature sensor 54. When the cabin temperature display setting is OFF, this display is not made.

(f, g) After displaying the cabin temperature, the idling time is displayed on the display unit 24. Here, (f) if auto-stop is disabled, when the vehicle is in an "idling state", the remaining idling time is displayed on the display unit 24. (g) When the engine is in an "engine stopped state", the set idling time is displayed on the display unit 24.

(h, i) On the other hand, when auto-stop is enabled, (h) in the "idling state", the elapsed idling time is displayed on the display unit 24. (i) in the "engine stopped state", "AUTO" is displayed on the display unit 24.

2-3. Extension of Idling Time During idling using the engine starter according to this embodiment, idling can be extended by 10 minutes once for the set idling time.

Figure 5 shows the display on the remote control and the sound emitted from the remote control when using the remote control to extend idling. (a) to (h) in the following explanation correspond to (a) to (h) in the figure, respectively.

(a) To extend the idling time, press the engine button 26b until the remote control 20 emits a beep to confirm operation. The display unit 24 will then flash "E."

(b) Next, while "E" is flashing (for approximately 3 seconds), press the start button 26a until the remote control 20 emits the "Do Re Mi Fa So" sound. The display unit 24 displays "START" along with a transmission animation, and an idling time extension signal is sent from the remote control 20. When the junction unit 40 recognizes the idling time extension signal, it sends a response signal back to the remote control 20.

(c) While waiting for a response signal from the junction unit 40, the backlight on the display unit 24 slowly flashes and a reception waiting animation is displayed in which horizontal bars 24a light up sequentially from left to right.

(d) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits the receiving sound "Do Re Mi Fa So Fa Mi Re Do," and (e, f) the display unit 24 alternates between "Ido" and "+10," notifying the user that the idling time has been extended.

(g, h) Here, when auto-stop is enabled, idling extension is disabled, the remote control 20 emits the reception sound "Do Re Mi Fa So Fa Mi Re Do," and the display alternates between the elapsed time and "I Do."

2-4 Stopping the Engine When the engine is started by the engine starter according to this embodiment, the engine can be stopped by the remote control 20.

Figure 6 shows the display on the remote control's display unit and the sound emitted from the remote control when the engine is stopped using the remote control. (a) to (d) in the following description correspond to (a) to (d) in the figure, respectively.

(a) To stop the car engine, press the engine button 26b until the remote control 20 emits a beep to confirm operation. The display unit 24 will show a flashing "E."

(b) Next, while "E" is flashing (for approximately 3 seconds), press the stop button 26c until the remote control 20 emits the "Do Re Mi Fa So" sound. The display unit 24 displays "STOP" along with a transmission animation, and a stop instruction signal is sent from the remote control 20. When the junction unit 40 recognizes the stop instruction signal, it sends an engine stop signal to the vehicle control device to stop the engine and sends a response signal back to the remote control 20. The engine stop signal sent by the junction unit 40 is the same signal as the engine stop signal sent from the key cylinder when the engine is stopped using a key.

(c) While waiting for a response signal from the junction unit 40, the backlight on the display unit 24 slowly flashes and a reception waiting animation is displayed in which horizontal bars 24a light up sequentially from left to right.

(d) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits the receiving sound "So Mi Re Do Re," the display unit 24 displays "OK," and an engine stop animation is displayed, notifying the user that the engine has stopped.

2-5. Door Locking/Unlocking Operation The remote control 20 of the engine starter according to this embodiment can be used to lock and unlock the doors of the vehicle.

Figure 7 shows the display on the remote control's display and the sound emitted from the remote control when using the remote control to lock or unlock the door. (a) to (h) in the following description correspond to (a) to (h) in the figure, respectively.

(a) To lock the door, press the start button 26a, which also serves as the lock button, until the remote control 20 emits a beep to confirm operation. The display unit 24 will flash a "locked padlock."

(b) Next, while "LOCKED PADLOCK" is flashing (for approximately 3 seconds), press the start button 26a again until the remote control 20 emits the "Do-Re-Mi-Fa-So" sound. "LOCKED PADLOCK" is momentarily displayed on the display unit 24, and a lock instruction signal is sent from the remote control 20. When the junction unit 40 recognizes the lock instruction signal, it sends a door lock signal to the door control device via the second connector 44 and the door lock line, and after the door control device locks the door, it sends a response signal back to the remote control 20.

(c) While waiting for a response signal from the junction unit 40, the backlight on the display unit 24 slowly flashes and a reception waiting animation is displayed in which horizontal bars 24a light up sequentially from left to right.

(d) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits a receiving sound "Sofa Mire Do," and the display unit 24 displays "Padlock in Locked State" and "OK," indicating that the door is locked.

(e) To unlock the door, press the stop button 26c, which also serves as the unlock button, until the remote control 20 emits a beep to confirm operation. The display unit 24 will flash an "unlocked padlock."

(f) Next, while "Unlocked Padlock" is flashing (for approximately 3 seconds), press the stop button 26c again until the remote control 20 emits the "Do-Re-Mi-Fa-So" sound. "Unlocked Padlock" is momentarily displayed on the display unit 24, and an unlock instruction signal is sent from the remote control 20. When the junction unit 40 recognizes the unlock instruction signal, it sends a door unlock signal to the door control device via the second connector 44 and the door unlock line, and after the door control device unlocks the door, it sends a response signal back to the remote control 20.

(g) While waiting for a response signal from the junction unit 40, the backlight on the display unit 24 slowly flashes and a reception waiting animation is displayed in which the horizontal bars 24a light up sequentially from left to right.

(h) When the remote control 20 receives a response signal from the junction unit 40, the remote control 20 emits a receiving sound "Sofa Mire Do," and the display unit 24 displays "Unlocked padlock" and "oK," indicating that the door has been unlocked.

2-6. Remote Control Registration Method The engine starter of this embodiment uses six channels: CH33 (922.4 MHz), CH34 (922.6 MHz), CH35 (922.8 MHz), CH36 (923.0 MHz), CH37 (923.2 MHz), and CH38 (923.4 MHz). The radio frequency is set to CH38 when the product is shipped. If a user attempts to register a remote control again using the same remote control 20 and the same junction unit 40, the wireless communication channel changes to the next channel (or the next channel if a carrier sense error occurs). The channel changes cyclically: CH38 → CH33 → CH34 → ... → CH38 → CH33. Even if the remote control 20 signal cannot be received on CH38 and a channel change is necessary (even if interference occurs), this remote control registration operation is performed near the junction unit 40, so there is no problem. Two remote control registration methods are described below. Since the remote control registration is completed when the product is shipped, the remote control registration work is performed to register the ID of a new remote control in the junction unit so that the new remote control can be used when the remote control in use is lost or broken.

(1) First Remote Control Registration Method Fig. 8 is an explanatory diagram of the first remote control registration method. The first remote control registration method will be explained below with reference to the same figure. <Step 1> to <Step 8> described in the following explanation correspond to <Step 1> to <Step 8> in the same figure, respectively.
<Step 1> Press and hold both the start button 26a and the stop button 26c on the remote control 20 simultaneously for about 5 seconds.
<Step 2> Press the stop button 26c until "Rmd" appears on the display 24 of the remote control 20. If no button is pressed for 20 seconds or more, the remote control 20 will emit a buzzer sound "beep beep beep" and the registration will be canceled.
<Step 3> Press the engine button 26b on the remote control 20. "REC" will appear on the display 24, and the remote control 20 will emit a series of confirmation beeps. If no button is pressed for 20 seconds or more, the remote control 20 will emit a beep beep beep sound, and the registration will be canceled.

Steps 4 to 7 below are to be performed while the confirmation beeps are being emitted from the remote control 20 (for approximately 40 seconds). If 40 seconds pass before Steps 4 to 7 are completed, the confirmation beeps will disappear and the registration will be canceled.
<Step 4> Insert the key 62 into the keyhole 64 provided on the vehicle body, and operate the key 62 to switch between ACC → ON → ACC → OFF three times within 7.5 seconds.
<Step 5> With the key 62 in the OFF position, the junction unit 40 emits a beeping sound for 10 seconds, followed by a beep. If the key 62 is operated while the beeping sound is being emitted, the registration is canceled.
<Step 6> Within 7.5 seconds after the beep is emitted from the junction unit 40, operate the key 62 to switch OFF → ACC → ON → ACC → OFF three times. A beep will be emitted from the junction unit 40. If 7.5 seconds pass before the three switches are completed, the registration will be canceled.
<Step 7> Press the engine button 26b until the remote control 20 emits the sounds "Do-Re-Mi.""REC" displayed on the display 24 flashes once, and a signal including the ID is transmitted from the remote control 20. When the junction unit 40 receives the signal including the ID and registers the ID, the junction unit 40 emits "beep, beep, beep" sounds and transmits a response signal to the remote control 20. When the remote control 20 receives the response signal transmitted from the junction unit 40, it emits the receiving sounds "Mi-Re-Do," and the display 24 displays "OK," notifying that remote control registration is complete.
<Step 8> Remove the key 62 from the keyhole 64.

(2) Second Remote Control Registration Method Figure 9 is an explanatory diagram of the second remote control registration method. The second remote control registration method will be explained below with reference to the same figure. <Step 1> to <Step 8> described in the following explanation correspond to <Step 1> to <Step 8> in the same figure, respectively.
<Step 1> Disconnect and reconnect the connector 42a from the first connector 42 of the junction unit 40. The junction unit 40 will emit a series of confirmation beeps: "beep beep beep beep beep."
<Step 2> Press and hold both the start button 26a and the stop button 26c on the remote control 20 simultaneously for about 5 seconds.
<Step 3> Press the stop button 26c until "Rmd" appears on the display 24 of the remote control 20. If no button is pressed for 20 seconds or more, the remote control 20 will emit a buzzer sound "beep beep beep" and the registration will be canceled.
<Step 4> Press the engine button 26b on the remote control 20. "REC" will appear on the display 24, and the remote control 20 will emit a series of confirmation beeps. If no button is pressed for 20 seconds or more, the remote control 20 will emit a beep beep beep sound, and the registration will be canceled.

The following steps 5 and 6 are performed while the confirmation beeps are being emitted from the remote control 20 (for approximately 40 seconds). If 40 seconds pass before steps 5 and 6 are completed, the confirmation beeps will disappear and the registration will be canceled.
<Step 5> Insert the key 62 into the keyhole 64 provided on the vehicle body and operate the key 62 to switch from OFF to ACC to ON. After about three seconds, the junction unit 40 will emit a beep.
<Step 6> Press the engine button 26b until the remote control 20 emits the sounds "Do-Re-Mi.""REC" displayed on the display 24 flashes once, and a signal including the ID is transmitted from the remote control 20. When the junction unit 40 receives the signal including the ID and registers the ID, the junction unit 40 emits "beep, beep, beep" sounds and transmits a response signal to the remote control 20. When the remote control 20 receives the response signal transmitted from the junction unit 40, it emits the receiving sounds "Mi-Re-Do," and the display 24 displays "OK," notifying that remote control registration is complete.
<Step 8> Operate the key 62 to switch from ON to ACC to OFF, and remove the key 62 from the keyhole 64.

3. Another Embodiment of Engine Starter Figure 10 is a block diagram showing an outline of another example of the configuration of an engine starter using a system according to the present invention. The figure shows the engine starter 10 being used in a vehicle 60 equipped with an immobilizer 66 (start permission device). In the figure, parts having substantially the same configuration as those of the engine starter shown in Figure 1 are designated by the same reference numerals. The engine starter 10 of this embodiment can be used in a vehicle 60 equipped with an immobilizer 66.

3-1. Overall Configuration An automobile 60 is provided with an engine 70 (drive unit), a vehicle control device 68, an immobilizer 66, and a junction unit 40, and the vehicle control device 68, the immobilizer 66, and the junction unit 40 are connected to one another by a cable 36. The remote control 20 and the genuine key 62a (password code transmitter) are carried by the user. Note that in Figure 10, dashed lines indicate connections via wireless communication (the same applies to Figures 11 and 12 described below).

The vehicle control device 68 starts the engine 70 based on a vehicle start signal. The vehicle start signal is transmitted from the remote control 20 when the user operates the remote control 20 to start the engine, and is then transmitted to the vehicle control device 68 from the junction unit 40 which receives this vehicle start signal. The vehicle start signal is also transmitted to the vehicle control device 68 by pressing a start button (not shown) provided on the automobile 60, or by inserting and turning the original key 62a into the keyhole. The original key 62a is included with the automobile at the time of sale, and transmits a pin code.

When the immobilizer 66 receives the pin code transmitted from the genuine key 62a, it compares this pin code with a reference code stored in a memory device provided in the immobilizer 66, and if they match, it transmits a start permission signal to the vehicle control device 68 to permit starting of the engine 70. When the vehicle control device 68 receives the vehicle start signal, it checks for the presence of the start permission signal for 20 ms, and if it confirms that the start permission signal is present during that time, it can start the engine 70.

In the engine starter 10 of this embodiment, both the remote control 20 and the junction unit 40 are equipped with the SX1272 communication chip, so that the wireless communication between the remote control 20 and the junction unit 40 can be selected between the LoRa method, which is a spread spectrum method, and the FSK method, which is a communication method other than the spread spectrum method. When used in a vehicle 60 equipped with an immobilizer 66 and when the user carries the original key 62a, the wireless communication method is the FSK method.

The remote control 20 can receive a personal identification code from the genuine key 62a, convert the received personal identification code into another code (hereinafter referred to as a "conversion code"), and transmit this conversion code to the junction unit 40. Hereinafter, "relaying a personal identification code" refers to "converting the personal identification code transmitted from the genuine key 62a into a conversion code by the remote control 20 and transmitting it to the junction unit 40, and then converting the conversion code back to the original personal identification code by the junction unit 40 and transmitting it to the immobilizer 66." In addition, the remote control 20 transmits a start command signal to the junction unit 40 when the user operates to start the engine.

When the junction unit 40 receives a conversion code from the remote control 20, it converts the conversion code back to the original PIN code and wirelessly transmits the converted PIN code to the immobilizer 66. Furthermore, when the junction unit 40 receives a start instruction signal from the remote control 20, it transmits a vehicle start signal to the vehicle control device 68 via the cable 36. Note that the communication distance between the genuine key 62a and the immobilizer 66 or remote control 20 is shorter than the communication distance between the remote control 20 and the junction unit 40.

3-2. Operation When a user performs an engine start operation using the remote control 20, a signal including a conversion code and a start instruction signal are transmitted from the remote control 20 to the junction unit 40.

Upon receiving the signal containing the conversion code and the start instruction signal, the junction unit 40 transmits the secret code to the immobilizer 66 and also transmits a vehicle start signal to the vehicle control device 68.

When the immobilizer 66 receives the PIN code, it compares it with a reference code stored in the immobilizer's memory device, and if they match, it sends a start permission signal to the vehicle control device 68 to allow the engine 70 to start.

If the vehicle control device 68 confirms the presence of a start permission signal within 20 ms of receiving the vehicle start signal, it will start the engine 70. Because the presence of the start permission signal must be confirmed within 20 ms of receiving the vehicle start signal, the FSK method is selected, which has faster communication and response speeds than the LoRa method. However, the distance over which remote control by the remote control 20 can be performed is shorter than with the LoRa method.

3-3. Other Usage Forms (1) When Used with a Genuine Key Placed Inside a Vehicle Equipped with an Immobilizer The engine starter of this embodiment can also be used when a genuine key is placed inside a vehicle equipped with an immobilizer.

Figure 11 is a block diagram showing an outline of another example of the configuration of an engine starter using the system of the present invention, showing the case where a genuine key is placed inside a vehicle equipped with an immobilizer. In this case, wireless communication between the remote control 20 and the junction unit 40 uses the LoRa method.

In this case, since the original key 62a is placed inside the automobile 60, the immobilizer 66 can constantly receive the PIN code transmitted from the original key 62a, and can also constantly send a start permission signal to the vehicle control device 68. In this case, the "relay PIN code" function is not used, so this function is turned off and the "non-relay mode" is selected.

When the user performs an engine start operation, a start instruction signal is transmitted from the remote control 20. Upon receiving this start instruction signal, the junction unit 40 transmits a vehicle start signal to the vehicle control device 68. If the vehicle control device 68 receives a start permission signal within 20 ms of receiving the vehicle start signal, it starts the engine 70.

The communication method is selected from either LoRa or FSK, whichever is available. The presence of the start permission signal must be confirmed within 20 ms of receiving the vehicle start signal, but since the start permission signal is transmitted from the genuine key 62a located inside the vehicle 60, either method can be selected. If the distance over which remote control is possible using the remote control 20 is prioritized, select LoRa packet mode (long distance mode). If communication speed and response speed are prioritized, select LoRa packet mode with a setting that increases the transmission bit rate compared to long distance mode (short distance mode).

(2) When used in a vehicle not equipped with an immobilizer The engine starter of this embodiment can also be used in a vehicle not equipped with an immobilizer.

Figure 12 is a block diagram showing an outline of another example of the configuration of an engine starter using the system of the present invention, showing its use in a vehicle without an immobilizer. In this case, wireless communication between the remote control 20 and the junction unit 40 uses the LoRa system.

In this case, since there is no immobilizer, when the user performs the engine start operation, a start instruction signal is sent from the remote control 20. The junction unit 40 receives this start instruction signal and sends a vehicle start signal to the vehicle control device 68. When the vehicle control device 68 receives a start permission signal, it starts the engine 70. In this case, too, the "relay PIN code" function is not used, so this function is turned OFF.

The communication method is selected from either LoRa or FSK, whichever is available. If communication speed and response speed are prioritized, select FSK, and if the distance over which remote control is possible using the remote control 20 is prioritized, select LoRa.

4. Modifications of the System According to the Present Invention In the engine starter using the system according to the present invention, the above-described two embodiments may be modified as follows.

The engine starter according to the above-described embodiment may transmit signals from at least one of the remote control 20 and the junction unit 40 at a strength below the noise floor.

In addition to the rod-type antenna 28 shown in Figure 2, the antenna used for wireless communication with the junction unit 40 included in the remote control 20 may also be a built-in antenna located inside the case 22.

The remote control 20 or junction unit 40 may allow the user to directly or indirectly change at least one of the signal transmission power level and the signal bit rate.

The engine starter according to the above-described embodiment may be configured to reduce transmission power when the signal strength received in the last communication between the remote control 20 and the junction unit 40 is -80 dBm or greater and transmission is performed within one minute of receiving the signal in the last communication, and to maintain transmission power at least at the transmission power level of the last communication when the signal strength is less than -80 dBm or transmission is performed one minute after receiving the signal in the last communication.

Furthermore, the engine starter according to the above-described embodiment may be configured to increase the transmission bit rate for transmitting signals when the signal strength information received in the last communication between the remote control 20 and the junction unit 40 indicates that the signal strength is -80 dBm or greater and the signal is transmitted within one minute of receiving the signal in the last communication, and to maintain the transmission bit rate at least at the transmission bit rate of the last communication when the signal strength is less than -80 dBm or the signal is transmitted one minute after receiving the signal in the last communication.

The engine starter according to the above-described embodiment is preferably configured to allow multiple spreading rates to be set for spread spectrum wireless communication, and to change the spreading rate for each packet transmission.

The engine starter according to the above-described embodiment may be able to communicate by switching the channel used for communication.

The engine starter according to the above-described embodiment may be configured to automatically switch to a channel for which a busy determination confirms that no signal is present. The busy determination of a channel is performed by the control unit 32 of the remote control 20 and the control unit 52 of the junction unit 40, with the level determination of spread spectrum signals being performed using the CAD function, and the level determination of signals using modulation methods other than spread spectrum being performed using RSSI. A busy determination is made when the signal level is -130 dBm or higher for spread spectrum signals, and when the signal level is -80 dBm or higher for signals using other modulation methods.

As shown in Figure 1, the system described above includes a remote control 20 (first device) and a junction unit 40 (second device) capable of wireless communication. The wireless communication between the remote control 20 and the junction unit 40 uses a spread spectrum system. The remote control 20 is portable, and the signals transmitted by the remote control 20 include signals that activate the functions of the junction unit 40. The function of the junction unit 40 is, for example, to transmit a vehicle start signal to the vehicle control device 68.

In this way, users can activate device functions by remote control using wireless communication over significantly longer distances than conventional FSK methods other than spread spectrum (frequency spread) methods, far surpassing the comparative distances of other companies. According to the results of experiments conducted by the inventors, device functions can be activated over distances roughly twice as long as conventional methods. For example, with conventional FSK methods, where the distance at which wireless communication is reliably possible is 1 km, spread spectrum methods enable communication over more than double that distance, at over 2 km.

At least one of the first device and the second device portable by the user may be any device, for example, a golf navigation system, and preferably a handheld device or remote control. In the above-described embodiment, a remote control 20 is used. For example, the signal transmitted from the remote control may include a signal for activating a function of the other device. At least one of the first device and the second device portable by the user may be particularly equipped with a function for inputting instructions from the user and configured to transmit a signal for activating a function of the other device based on the input instruction. The function for inputting instructions from the user may be any device that can input instructions, but preferably is a sensor capable of detecting user movement, etc., and particularly preferably is equipped with a means for inputting user instructions. At least one of the first device and the second device portable by the user may be a wearable terminal that can be attached to the body. Preferably, at least one of the first device and the second device portable by the user is a device that can be held in the hand and is equipped with a function for inputting instructions by hand. Preferably, it is equipped with a means for inputting instructions by pressing with the fingers of the hand. More preferably, the means for inputting instructions should be configured as a switch.

The other of the first device and the second device may be any device, but for example, it may be a device that is portable by the user, preferably a device that is not portable by the user, such as a device fixed to an object, and more preferably a device installed indoors. When fixed to an object, it may be fixed to the ground, for example, and preferably to a gas, electricity, or water meter. When fixed to the ground, it may be a water sprinkler, for example. When fixed to a gas, electricity, or water meter, it may be a terminal device that transmits meter reading data to a remote control. When installed indoors, it may be installed in a golf clubhouse or inside a car. When installed in a clubhouse, it may be digital signage, for example. When installed inside a car, it may be an on-board device, for example. In the above-described embodiment, a junction unit 40 is used that is installed in a car.

The system of the present invention may be any system, but is particularly suitable for use in consumer devices and various industrial devices, and is particularly suitable for use in automotive-related devices such as the engine starter mentioned above. This allows users to remotely control various devices appropriately.

For example, in a system for use with consumer devices, one of the first device or second device that can be carried by the user can be a remote control, and the other can be a device fixed to the ground, and the signal transmitted from the remote control can include a signal that activates a function of the device.

For systems used in consumer devices, it is desirable that one of the first or second devices, which can be carried by the user, is a portable device, and the other is a transmitter fixed to a gas, electricity, or water meter, etc. The signal sent from the transmitter to the portable device should include meter reading data and a signal that causes the portable device to compile this meter reading data (a signal that activates the functions of the portable device).

In particular, it is desirable to use a wireless communication system that uses a standard called "Wi-SUN (Wireless Smart Utility Network)," which is equipped with a terminal fixed to a gas, electricity, or water meter, and collects meter reading data via wireless communication using a portable device or the like. Using the system of the present invention with Wi-SUN allows users to collect meter reading data from even more remote locations than before, minimizing the travel effort required for data collection. For example, when reading an electricity meter in a mountainous area far from roads accessible by car and accessible only by foot, a meter reader carrying a portable device is more likely to be able to collect meter reading data (hereinafter also referred to as "meter information") within the range of travel by car, thereby increasing the possibility of shortening the travel distance even if walking is required after traveling by car. In particular, it is desirable for the portable device to be portable and move around on foot, allowing instructions to be entered manually.

More preferably, this system would have the first device be a golf navigation system and the second device be a digital signage installed in the clubhouse. In particular, the signal transmitted from the golf navigation system would include a signal that activates the display and tallying functions of the digital signage. In this case, it would be possible to display the rankings of players entered into the golf navigation system during a round on the digital signage, saving the user the trouble of tallying up player results, etc.

A system for use in automobile-related equipment may be, for example, a system for use in an automobile engine starter or car security system, with the first device being a remote control and the second device being an onboard device. In the above-described embodiment, the system is an automobile engine starter. In particular, the signal transmitted from the remote control may include a signal that activates a function of the onboard device, and the signal transmitted from the onboard device may include a signal that activates a function of the remote control. Preferably, the signal transmitted from the remote control is transmitted based on instructions from the user.

Here, with conventional engine starters and car security devices, for example, in large apartment buildings, there were cases where the parking lot was too far from the user's room to be usable. This problem was particularly pronounced in tower apartments. Furthermore, for example, there were cases where radio waves were blocked by concrete walls, making it impossible to use the device without going out onto the balcony. However, even in such cases, with the present invention, the user can more reliably activate the function of the other device than before. For example, the engine starter or car security function can be activated more reliably than before. Therefore, for example, even in cases where the user previously had to move to a location where radio waves could reach the car in the parking lot more easily, such as a window or balcony, to activate the function of the other device, the user is more likely to be able to activate the engine starter or car security by operating it from a location indoors, such as next to the bed.

Furthermore, for example, a system for automotive-related devices equipped with the above-mentioned remote control (portable device) and in-vehicle device could be combined with a wireless communication system that collects Wi-SUN meter information, etc., so that the in-vehicle device acts as a gateway (intermediate) to transmit meter information generated in the home to the portable device. Specifically, for example, the in-vehicle device could receive information such as gas, electricity, and water meter reading data and power generation data from a solar-powered power generator installed in the home from a Wi-SUN device in Wi-SUN mode (a modulation method other than spread spectrum), and the in-vehicle device could then transfer this received information to the user's portable device (remote control) in spread spectrum mode. This would allow users to receive meter reading data and other information within a wider cycling range than the conventional walking range. For example, in conditions where conventional Wi-SUN mode (a modulation method other than spread spectrum) only had a range of about 1 km, lowering the bit rate using spread spectrum would extend the range to 6 km. A 1km diameter from the center of one's home is considered to be within the daily living area (walking distance), while a 6km diameter is considered to be the local living area. Also, usually, almost everything can be done within this local living area (biking distance) from one's home.

Preferably, the first device is fixed to an object, and the second device is portable by the user. The user carrying the second device can activate the functions of the first device at the location of the object to which the first device is fixed, without using the second device. The second device is carried by the user and moves as the user moves on foot or bicycle, with the location of the object to which the first device is fixed as a base point (e.g., the starting point of the movement). The second device returns to the base point (e.g., the original starting point as the end point after moving to a predetermined destination) when the user moves to the location of the object to which the first device is fixed. The "movement on foot or bicycle" should be a line-of-sight distance of 5 km to 20 km. For example, the base point may be the user's home, and the user may be an elderly person with dementia. Alternatively, the base point could be an automobile, with the user walking from the automobile, shopping at a shopping center, for example, and starting the engine while shopping, before returning to the automobile, which is the base point. Alternatively, the base point could be an automobile, with the user walking from the automobile to their home after returning home, and starting the automobile engine from inside their home the next morning before returning to the automobile. Alternatively, the base point could be a clubhouse, with the user walking around the golf course while playing, and returning to the clubhouse after playing.

Also, for example, the first device may be a single base unit installed in a nursing facility, and the second device may be a handset carried by multiple residents of the nursing facility. Each handset is assigned a different ID, and the base unit stores the correspondence between the ID and the name of the person carrying the handset. Each handset transmits radio waves containing the ID using a spread spectrum method at regular intervals (e.g., every minute). The base unit checks the ID and RSSI (Received Signal Strength Indicator) of the received radio waves, and when the RSSI of the received radio waves falls below a set value, displays on the base unit the approximate distance from the base unit to the handset that transmitted the radio waves and the name of the person associated with that ID. The "RSSI setting value" may be determined in advance by determining the relationship between the distance between the base unit and the handset and the RSSI value, and storing this value in the base unit, allowing it to be entered and set as the distance. Alternatively, "when the RSSI falls below a set value" may be when the RSSI level reaches that equivalent to that outside the care facility, based on the difference in RSSI measured in advance between inside and outside the facility and set in advance.

The base unit may have the function of selecting a person's name stored in advance from a list, etc., and the function of wirelessly transmitting a signal requesting a response to a slave unit with an ID corresponding to that person's name. If the received ID is its own ID and a response is requested from the base unit, the slave unit wirelessly transmits level information regarding the received electric field strength and its own ID. The base unit determines and displays the position of the slave unit (e.g., distance from the base unit) from the electric field strength level of the received ID.

Furthermore, it is preferable to provide a function for relaying wireless inquiry signals from the base unit between sub-units. For example, the base unit may be equipped with a "normal search button (search without relay)" and a "search with relay" button. When the "normal search button" is pressed, it requests a response from all sub-units within the range of the base unit's radio waves, including their IDs and field strength levels. On the other hand, when the "search with relay" button is pressed, it requests a response from all sub-units within the range of the base unit's radio waves and from all sub-units within the range of those sub-units. The responses (e.g., the IDs and field strength levels of other sub-units) are relayed by the sub-units between the base unit and the other sub-units. Note that further relaying between sub-units may be performed, and it is preferable to set a limit on the number of relays between sub-units. Furthermore, the base unit and sub-units may each be equipped with a location detector such as a GPS, so that only sub-units within a range specified by the base unit from the base unit's location will be relayed.

Communications using the "spread spectrum method" can involve, for example, modulating the signal to be transmitted, spreading the modulated narrowband signal to a wideband using a specified spreading method, thereby reducing the power density, and then transmitting the signal from the transmitting side. On the receiving side, the received signal can be despread to obtain the original narrowband signal with higher power density. Furthermore, the "spread spectrum method" can be particularly configured to restore the original narrowband signal with higher power density by despreading, even if the spread signal received on the receiving side is a weak signal below the so-called noise floor, and then demodulate the restored original narrowband signal to reproduce it as the signal that was intended to be transmitted. In this way, it is possible to receive signals that have attenuated below the noise floor over long distances.

In addition, in communications using the "spread spectrum method," modulation of the spread signal on the transmitting side and demodulation of the spread signal on the receiving side can be performed using hardware modulators and demodulators, or by software defined radio. In particular, it is preferable to use an IC chip that performs the calculations equivalent to such modulation and demodulation.

Any communication method may be used as the "spread spectrum method," but it is particularly preferable to use a method that increases communication distance even at the expense of communication speed. For example, a frequency hopping method is preferable. It is preferable to use a method other than a direct sequence spread spread method. More preferably, the "spread spectrum method" is a method that generates a chirp signal by continuously changing the frequency, and this spreads and modulates a signal based on the data to be transmitted (hereinafter referred to as the "chirp method"). It is particularly preferable to combine the chirp method with other methods. For example, it is preferable to combine the chirp method with at least one of a frequency hopping method and a direct sequence spread spread method. Furthermore, it is most preferable to use the LoRa method, which will be described in detail later, as the "spread spectrum method." Conversely, conventional modulation methods other than spread spectrum include the above-mentioned FSK method, as well as OOK (on-off keying), GFSK (phase-continuous FSK), MSK (minimum shift keying), and GMSK (Gaussian minimum shift keying) (hereinafter, these modulation methods will be collectively referred to as "FSK, etc.").

Furthermore, the "first device and/or second device" that is "portable by the user" may be any device, but may be, for example, a mobile communication device, a mobile information device, a wearable terminal, etc. Furthermore, the "first device and/or second device" that is "portable by the user" may be, for example, a non-dedicated device that can perform functions other than remote control, but may particularly be a dedicated device for remote control, such as a remote control.

The "signal transmitted by the one device" may include a signal that activates a function of the other of the first device or the second device. For example, in the case of an engine starter or car security, the signal may include a signal to start, stop, or change settings of these devices. For example, in the case of an engine starter or car security, the signal may include a signal to activate an alarm function from these devices to a portable device or remote control. Preferably, the "signal transmitted by the one device" may include a signal other than a signal that activates a function of the other device. For example, in the case of a car security, the "signal other than a signal that activates a function of the other device" may be data detected by a sensor installed in the vehicle, such as the degree of impact to the vehicle. In this embodiment, the signal is the current cabin temperature of the engine starter.

In addition, the "signal transmitted by the one device" may be configured to include start and stop signals for consumer devices such as water sprinklers and various industrial devices. In addition, in devices such as golf navigation systems, the "signal transmitted by the one device" may be configured to include signals such as player performance information entered into the golf navigation system. Furthermore, when the system of the present invention is used in devices such as gas, electricity, or water meters that use standards such as Wi-SUN, the "signal transmitted by the one device" may be configured to include various data such as meter reading data.

For example, if the first device is a portable device such as a remote control and the second device is an in-vehicle device, the portable device may be configured to use the single receive mode and the in-vehicle device to use the continuous receive mode. This configuration extends the battery life of the portable device and allows the in-vehicle device to more reliably capture signals transmitted from the portable device. In this configuration, it is desirable for the in-vehicle device to transmit the same information multiple times. This reduces the occurrence of missed readings due to external disturbances in the portable device. Even more desirable is a function to send a signal from the in-vehicle device to the portable device indicating that it should switch to continuous receive mode, and when the portable device receives this signal, it operates in continuous receive mode. In such a configuration, it is particularly advantageous to set the time for operation in continuous receive mode to a fixed period of time. This type of communication mode can be implemented, for example, by using the communications chip "SX1272."

The "Single receive mode" is, for example, a mode in which only one packet is received within a set time. In particular, when communicating at a fixed reception timing, it is recommended that the receiving circuit be configured to turn on only at the required reception timing. This reduces power consumption during reception standby. The "Continuous receive mode" is, for example, a mode in which signals are received continuously.

In this embodiment, the wireless communication between the remote control 20 and the junction unit 40 is LoRa, which uses spread spectrum technology.

This allows users to break away from the current situation where the distance at which remote control is possible is generally uniform.

A wireless system using a spread spectrum method, particularly a LoRa method (hereinafter also referred to as a "LoRa wireless system"), can communicate at a higher transmission bit rate (hereinafter simply referred to as "bit rate", "data rate" or "transmission speed") when designed for the same communication distance as an FSK method, for example. A higher bit rate shortens communication time, so the user can obtain a system that can quickly activate one of the functions of the remote control 20 and the junction unit 40 when sending a signal to activate the other function from either the remote control 20 or the junction unit 40.

In this embodiment, the remote control 20 has a function for inputting instructions from the user and is configured to transmit signals that activate the functions of the junction unit 40 based on the input instructions. This results in a system that responds quickly to input instruction operations.

It is desirable to set the bit rate low in the LoRa system. This allows for higher sensitivity. Most desirable is to set the bit rate as low as possible. In particular, it is desirable to set the bit rate as low as possible on the remote control 20 that the user can carry. In this way, the user can transmit a signal to activate the function of the junction unit 40 from the remote control 20 from a longer distance than before, and cause the junction unit 40 to activate the function. It is also desirable, for example, to set the bit rate of the remote control 20 lower than the bit rate of the junction unit 40.

It is desirable to set the bit rate low in this way, especially in systems that transmit and receive small amounts of digital information. It is even more desirable to set the bit rate low when transmitting digital information such as for car security or the engine starter of this embodiment.

In this embodiment, LoRa wireless communication is implemented using the SEMTECH SX1272 communications chip. This communications chip performs the modulation and demodulation of the above-mentioned signals through arithmetic processing.

In this embodiment, wireless communication between the remote control 20 and the junction unit 40 uses the sub-gigahertz band, and the channel bandwidth used is a sub-gigahertz frequency channel that is wider than the bandwidth of channels in frequency bands below the sub-gigahertz band.

This allows users to operate device functions by remote control using wireless communication, using a smaller device than before and over longer distances than before. Radio waves generally have a shorter range in the sub-gigahertz band than in frequency bands below sub-gigahertz, but this problem of short range can be solved by using sub-gigahertz frequency channels with a wider bandwidth than the bandwidth of channels in frequency bands below sub-gigahertz. In this embodiment, sub-gigahertz frequency channels are set whose channel bandwidth is wider than the bandwidth of channels in frequency bands below sub-gigahertz.

In this embodiment, the sub-gigahertz band is used as the frequency of the oscillators provided in the remote control 20 and junction unit 40 for wireless communication, and sub-gigahertz frequency channels are used, with the bandwidth of the channels used being wider than the bandwidth of channels in frequency bands below the sub-gigahertz band. The wireless communication frequencies are set by the control unit 32 provided in the remote control 20 and the control unit 52 provided in the junction unit 40. Furthermore, both the control unit 32 and the control unit 52 are equipped with microcomputers, and write values corresponding to the frequencies to be set into registers of the microcomputers.

Furthermore, in this embodiment, the wireless communication between the remote control 20 and the junction unit 40 is specified low-power wireless, using the sub-gigahertz band, and the transmittable power used is a sub-gigahertz frequency that is greater than the transmittable power in frequency bands below the sub-gigahertz band.

In this embodiment, the "frequency bands below the sub-gigahertz band" are the bands of 426.0250 to 426.1375 MHz, 426.0375 to 426.1125 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, and 429.8125 to 429.9250 MHz. In each of these bands, the channel bandwidth is 12.5 kHz, and in particular, 25 kHz in the band of 426.0375 to 426.1125 MHz. Furthermore, the transmittable power is 1 mW in the bands of 426.0250 to 426.1375 MHz and 426.0375 to 426.1125 MHz, and 10 mW in each of the other bands.

In this embodiment, the "sub-gigahertz band" refers to a band with a center frequency of 916.0 to 928.0 MHz, with a channel bandwidth of 200 kHz. Furthermore, channels used in the sub-gigahertz band are sub-gigahertz channels with a bandwidth of 200 kHz, which is 16 times the 12.5 kHz bandwidth of channels in the 426.0250 to 426.1375 MHz, 429.1750 to 429.2375 MHz, 429.2500 to 429.7375 MHz, or 429.8125 to 429.9250 MHz bands. Furthermore, the transmittable power is 20 mW. Channels used in the sub-gigahertz band have a transmittable power of 20 mW, which is twice the transmittable power of 10 mW in frequency bands below the sub-gigahertz band.

In the 400 MHz band, which is included in the "sub-gigahertz frequency band," Japanese laws and regulations at the time of filing allocate a bandwidth of 12.5 kHz or 25 kHz per channel. Meanwhile, in the sub-gigahertz band, there is the 920 MHz band, which allocates a bandwidth of 100 kHz or 200 kHz per channel. As such, the 920 MHz band is a particularly good sub-gigahertz band, as it has a wider bandwidth per channel than the 400 MHz band, which is a sub-gigahertz frequency band. While the 400 MHz band has a narrower bandwidth per channel than the 920 MHz band, its radio waves have the advantage of reaching farther distances and being less directional and more prone to diffraction, making them easier to receive even behind distant obstacles (mountains or buildings).

In this embodiment, the "channel to be used" is at least one of six channels with center frequencies of 922.4 MHz, 922.6 MHz, 922.8 MHz, 923.0 MHz, 923.2 MHz, and 923.4 MHz (each with a bandwidth of 200 kHz), and some of these channels can be switched. It is preferable to have a configuration in which the system automatically switches to one of these channels for which it is determined that no signal is present through a busy determination. These channels may also be configured to use a wider bandwidth by combining multiple adjacent channels; for example, it is preferable to combine five adjacent channels of the six channels mentioned above to use a bandwidth of 1000 kHz.

In this embodiment, a "channel" is a frequency band allocated for use in communications, and is a frequency band allocated under Japanese laws and regulations.

When determining whether a channel is busy, the CAD function is used to determine the level of spread spectrum signals, while the RSSI is used to determine the level of signals using modulation methods other than spread spectrum. The CAD function detects the presence of spread spectrum signals at levels so low that they cannot be detected using RSSI. A busy state is determined to be busy when the signal level is -130 dBm or higher for spread spectrum signals, and when the signal level is -80 dBm or higher for signals using other modulation methods. This allows for more accurate channel busy determination, making it possible to operate device functions over long distances by remote control using wireless communication.

As shown in Table 1 above, when "RSSI present" and "CAD present" are present, the busy determination is either (A) due to the presence of both a spread spectrum signal and a signal using a modulation method other than spread spectrum, or (B) due to the presence of a relatively strong spread spectrum signal (-80 dBm or higher). Therefore, in case (A), the transmission of signals using all modulation methods is prohibited, while in case (B), the transmission of signals using modulation methods other than spread spectrum is possible. Furthermore, even in case (A), transmission is possible if the spread spectrum signal has a different bandwidth and spreading rate from the existing spread spectrum signal.

When "RSSI present" and "CAD absent" are displayed, the busy status is determined to be due to the presence of a signal using a modulation method other than spread spectrum. Since no spread spectrum signal is present, spread spectrum signals can be transmitted.

When "RSSI not present" and "CAD present", the busy status is determined to be due to the presence of a spread spectrum signal. Since there are no signals using modulation methods other than spread spectrum, it is possible to transmit signals using modulation methods other than spread spectrum. Furthermore, even if a signal uses spread spectrum, it can be transmitted as long as the bandwidth and spreading rate differ from those of the existing spread spectrum signal.

When "RSSI not present" and "CAD not present" there is no busy detection, and since there are no spread spectrum signals or signals using modulation methods other than spread spectrum, signals using all modulation methods can be transmitted.

In this embodiment, the strength of the signal transmitted from the remote control 20 or junction unit 40 is not particularly specified, but it is preferable that it be below the noise floor.

This significantly reduces the possibility of interference with signals using modulation methods other than spread spectrum, such as FSK. Methods for keeping the signal strength below the noise floor include, for example, reducing the transmission power, or transmitting the signal at a high spreading rate that keeps the signal strength below the noise floor. While a higher spreading rate slightly reduces the transmission speed of the transmitted signal, it also has the advantage of improving communication sensitivity and extending communication distance. Therefore, this allows users to operate device functions remotely via wireless communication over longer distances than before. A "noise floor" of -80 dBm is recommended.

In this embodiment, wireless communication between the remote control 20 and the junction unit 40 using the spread spectrum method enables signals to be transmitted with the same power at one of the quarter portions of the bandwidth from both ends of the bandwidth of the channel being used, and at the center of the bandwidth.

This allows users to operate device functions remotely using wireless communication over longer distances than before. Such systems, which have high modulation efficiency and are capable of communication at high transmission bit rates, can be implemented using, for example, spread spectrum and LoRa systems. On the other hand, with FSK systems, the signal transmission power decreases at the high-frequency and low-frequency ends of the bandwidth, and the signal extends outside the bandwidth, resulting in low modulation efficiency.

Spread spectrum wireless communication between the remote control 20 and the junction unit 40 preferably allows signals to be transmitted at the same power near both ends of the bandwidth of the channel being used, up to a quarter of the bandwidth inside the band, and near the center of the bandwidth. More preferably, signals should be transmitted at the same power near at least one end and near the center of the bandwidth of the channel being used. Even more preferably, signals should be transmitted at the same power across the entire bandwidth of the channel being used.

In particular, it is advisable to configure the power used to transmit signals outside the bandwidth of the channel being used to be less than a specified value. This will result in a higher modulation efficiency, as the amount of signal that extends outside the bandwidth will be less than the specified value. When the same communication distance is set in a communication system, the higher the modulation efficiency, the higher the bit rate at which communication is possible.

In this embodiment, the remote control 20 and junction unit 40 use the "SX1272" communications chip, which means that power consumption does not change even when the transmission bit rate is changed. Therefore, when the transmission bit rate is increased and the communication time is shortened, the current consumption of the device decreases, thereby reducing power consumption in the system. The remote control 20 uses a battery as its power source, which extends battery life. This allows users to minimize the hassle of battery replacement, etc.

At least one of the remote control 20 and the junction unit 40 may be a device whose power consumption increases when the transmission bit rate is increased. In particular, it is advisable to set the transmission bit rate so that the reduction in transmission power due to shorter communication time exceeds the increase in power consumption caused by increasing the transmission bit rate. In this way, overall power consumption can be reduced, and battery life can be extended.

In addition, in this embodiment, the wireless communication between the remote control 20 and the junction unit 40 may be configured to use a method that allows transmission at the same power at the center of the entire width and at one peripheral end, instead of or in addition to the spread spectrum method. In particular, it is desirable to use a method that allows signals to be transmitted at the same power across the entire bandwidth of the channel being used. Furthermore, for example, the wireless communication between the remote control 20 and the junction unit 40 may use the OFDM modulation method, instead of or in addition to the spread spectrum method. In particular, it is desirable to use Wi-Fi HaLow (IEEE 820.11ah).

The wireless communication between the remote control 20 and the junction unit 40 should be configured to use GFSK modulation instead of, or in addition to, the spread spectrum method. Preferably, this should be at a speed of several hundred bits per second or less than the GFSK modulation. Even more preferably, Sigfox should be used.

Furthermore, wireless communication between the remote control 20 and junction unit 40 may be performed via wireless network communication, but it is preferable to perform one-to-one communication between the remote control 20 and junction unit 40. The communication chip "SX1272" should be configured to use, for example, 0x12 as the SyncWord value, rather than 0x34, which is used in LoRaWAN. Preferably, it should be configured to use a value other than 0x34 or 0x12. This reduces the possibility of interference with commercially available devices that use LoRa wireless communication.

In this embodiment, the remote control 20 and junction unit 40 use an externally exposed antenna 28 or antenna unit 56, but it is particularly preferable for the remote control 20 to be equipped with a built-in antenna for wireless communication.

This allows users to use devices with simple configurations where the antenna is not exposed to the outside, particularly the highly portable remote control 20. This is because a wireless system using spread spectrum technology can use an antenna with lower antenna gain when designed for the same communication distance and the same communication bit rate as a wireless system using FSK technology.

This effect is particularly pronounced in wireless systems that use the LoRa method, as in this embodiment. Furthermore, while typical spread spectrum wireless systems (WLAN, WCDMA, etc.) strive to prevent interference and achieve high bit rates, the LoRa method significantly improves sensitivity by spreading low bit rate signals over a wide band using spread spectrum, consuming a large bandwidth. Therefore, by adopting the LoRa communication method, it is possible to further miniaturize the built-in antenna. This allows the system to be used without any hassle, even when the user carries the portable device in a pocket, etc.

As such, LoRa wireless systems have high communication sensitivity, allowing the use of smaller antennas with lower gain. Therefore, by adopting a LoRa wireless system, it becomes possible to use a remote control (portable device) that, despite having a built-in antenna, achieves radio wave ranges comparable to those of remote controls using conventional rod antennas, providing users with a system that allows for highly portable remote controls (portable devices).

In this embodiment, wireless communication between the remote control 20 and the junction unit 40 is LoRa, using the sub-gigahertz band. The bandwidth and transmittable power of the channel used are wider than those of channels in frequency bands below the sub-gigahertz band, and are greater than those of channels in those bands. Because the sub-gigahertz band frequency channel is a sub-gigahertz band, there are significant benefits to having a built-in antenna.

In this embodiment, the magnitude of the signal transmission power may be changed directly or indirectly by the user.

This allows users to use the system with optimal transmission power depending on their environment. For example, if the distance between the remote control 20 and the junction unit 40 is short and the communication environment is relatively good, the transmission power can be minimized by setting the transmission power low within a range that does not cause problems with signal transmission. For remote control 20 that uses battery 34 as its power source, users can extend battery life and reduce the frequency of battery replacement, etc. On the other hand, if users want to prioritize reliable signal transmission between the remote control 20 and the junction unit 40 over minimizing transmission power, they can set the transmission power higher, taking into account the expected communication distance, etc. This ensures reliable signal transmission, allowing users to accurately control devices equipped with the system of the present invention.

Here, a configuration in which "the magnitude of the signal transmission power can be directly changed by the user" may be one in which the magnitude of the transmission power of the remote control 20 or junction unit 40 is set by inputting a power value, for example. By allowing "the magnitude of the transmission power to be directly changed by the user" in this way, the user can accurately adjust the transmission power to a level that is appropriate for their own usage conditions.

A configuration that allows the user to indirectly change the magnitude of the signal transmission power may, for example, be one in which the magnitude of the transmission power of the remote control 20 or junction unit 40 is set using a relative numerical value or index associated with the power value. Various indices associated with the power value can be considered, such as "strong, medium, weak," or an index based on the operating mode. In particular, a configuration that allows the user to select between a "long-distance communication mode (normal mode)" and a "long-life mode" with a long battery life is particularly desirable. This allows the user to choose whether to prioritize battery life or the distance at which the device's functions can be activated by remote control using wireless communication. By allowing the user to "indirectly change the magnitude of the transmission power" in this way, the user can intuitively or intuitively adjust the output to a level of transmission power that suits their own usage conditions.

The configuration "allowing the user to directly or indirectly change the magnitude of the signal transmission power" may be any configuration, preferably via switches (e.g., dip switches) or a control device provided on a junction unit 40 that the user cannot carry, and particularly preferably via a remote control 20 that the user can carry.

The signal transmission power level may be changed based on the operation of an operation unit provided on the remote control 20 or other device. The operation unit may be configured, for example, as a slider, or as a slider displayed on a display screen provided on the remote control 20 or other device.

It is desirable to configure the remote control 20 to allow selection between the aforementioned "long-distance communication mode (normal mode)" and "long-life mode." In this way, the user can extend battery life by selecting long-life mode in areas where communication is possible in long-life mode, and when communication in long-life mode becomes impossible in areas farther away than the area where communication is possible in long-life mode, the user can switch to long-distance communication mode and activate the functions of the other device by remote control using wireless communication.

Furthermore, when setting the operating mode according to the magnitude of the signal transmission power, such as "long-distance communication mode (normal mode)" or "long-life mode," each mode may be set in multiple stages or continuously according to the magnitude of the transmission power. By adopting these methods, the user can easily and accurately adjust the magnitude of the signal transmission power.

In this embodiment, the signal transmission bit rate may be changed directly or indirectly by the user.

In this way, by adjusting the transmission bit rate, the user can use the system under conditions that are optimal for their environment. For example, by setting a low transmission bit rate, the user can improve communication sensitivity while ensuring a larger communication range. Conversely, by setting a high transmission bit rate, the user can minimize communication time at the expense of communication sensitivity and communication distance, enabling agile communication operations and remote control of device functions over long distances using wireless communication.

In this embodiment, the remote control 20 and junction unit 40 use the "SX1272" communications chip, which means that power consumption does not change even when the transmission bit rate is changed. Therefore, when the transmission bit rate is increased and the communication time is shortened, the current consumption of the device decreases, thereby reducing power consumption in the system, and particularly in the device that transmits the signal. The remote control 20 uses a battery as its power source, which extends battery life. This allows users to minimize the hassle of replacing batteries, etc.

At least one of the remote control 20 and the junction unit 40 may be a device whose power consumption increases when the transmission bit rate is increased. In particular, it is advisable to set the transmission bit rate so that the reduction in transmission power due to shorter communication time exceeds the increase in power consumption caused by increasing the transmission bit rate. In this way, overall power consumption can be reduced, and battery life can be extended.

Here, an example of a configuration that allows the user to directly change the signal transmission bit rate is a configuration in which the transmission bit rate of the remote control 20 or junction unit 40 is set by inputting a bit rate value. By allowing the user to directly change the magnitude of the transmission bit rate in this way, the user can accurately adjust the transmission bit rate to suit their own usage conditions.

A configuration that allows the user to indirectly change the signal transmission bit rate may, for example, be one in which the transmission bit rate of the remote control 20 or junction unit 40 is set using a relative numerical value or index associated with the transmission bit rate. Various indices associated with the transmission bit rate are possible, such as "large, medium, or small," or an index based on the operating mode. In particular, it may be possible to select between a "normal mode" and a "speed mode" that provides fast communication. This allows the user to choose whether to prioritize the distance at which device functions can be activated by remote control using wireless communication, or the speed of communication. By allowing the user to indirectly change the signal transmission bit rate in this way, the user can intuitively or intuitively adjust the transmission bit rate to a level that suits their own usage conditions.

The configuration "allowing the user to directly or indirectly change the signal transmission bit rate" may be any configuration, preferably via switches (e.g., dip switches) or a control device provided on a junction unit 40 that the user cannot carry, and in particular, preferably via a remote control 20 that the user can carry.

It is desirable to configure the remote control 20 to allow selection between the above-mentioned "normal mode" and "speed mode." In this way, the user can select speed mode in areas where communication is possible in speed mode, thereby making communication operations more agile. When communication in speed mode becomes impossible in areas farther away than the area where communication is possible in speed mode, the user can switch to normal mode and activate the functions of the other device by remote control using wireless communication.

The transmission bit rate may be changed, for example, by operating an operation unit on a remote control or other device. The operation unit may be configured, for example, as a slider, or as a slider displayed on a display screen on the remote control or other device.

Furthermore, when setting the operating mode according to the transmission bit rate, such as "normal mode" or "speed mode," each mode may be set in multiple stages or continuously according to the transmission bit rate. By adopting these methods, the user can easily and accurately adjust the signal transmission bit rate.

In this embodiment, if the information regarding the strength of the signal received in the last communication between the remote control 20 and the junction unit 40 indicates that the signal strength is -80 dBm or greater and transmission occurs within one minute of receiving the signal in the last communication, the transmission power is reduced; if the signal strength is less than -80 dBm or transmission occurs one minute after receiving the signal in the last communication, the transmission power is maintained at least at the transmission power level of the last communication.

This allows the user to optimize transmission power consumption while ensuring reliable signal transmission and reception in the system. For example, if the signal strength received by the device in the last communication is stronger than necessary, the next transmitted signal strength can be reduced. Because at least one of the remote control 20 and the junction unit 40 is portable, even if the signal strength received by the device is stronger than necessary, the distance between the remote control 20 and the junction unit 40 may increase over time as the user moves. In this way, if the transmission power for the next communication can be adjusted based on the signal strength received by the device in the last communication, it is advisable to use time as an index to estimate the change in the distance between the remote control 20 and the junction unit 40 and adjust the transmission power based on this estimation. In this embodiment, the transmission power is reduced not only when the signal strength received in the last communication is -80 dBm or greater, but also when the next signal is transmitted within one minute of receiving the signal in the last communication. Furthermore, this embodiment is configured to maintain at least the transmission power when the signal strength is below a predetermined value or when a predetermined time has elapsed since receiving the signal in the last communication. This allows the user to operate the device's functions remotely over long distances using wireless communication, while also reducing transmission power consumption. Furthermore, for remote controls 20 that use batteries as their power source, battery life can be extended, eliminating the need for users to frequently replace batteries.

Here, the "predetermined time" for reducing transmission power, defined as "one minute," may be set based on the estimated distance at which communication would still be possible between the remote control 20 and the junction unit 40 even if the distance between them were to increase, and the assumed speed at which the distance between the remote control 20 and the junction unit 40 would increase, for example, when attempting to reduce the transmission power of the next signal to be transmitted below the transmission power used in the last communication. For example, assuming that the distance between the remote control 20 and the junction unit 40 increases as the user carrying the remote control 20 moves on foot, the "predetermined time" may be set based on the relationship between the average walking speed of an average adult, the estimated distance at which communication would still be possible between the remote control 20 and the junction unit 40 after the transmission power is reduced, and the expected reduction in communication distance due to the reduction in transmission power. In this way, by using time as an index to estimate changes in the distance between the remote control 20 and the junction unit 40, setting a "predetermined time" based on this estimated result, and using this predetermined time as one of the criteria for reducing transmission power, the user can operate the device's functions over long distances by remote control using wireless communication without any inconvenience, even when control is performed to reduce transmission power consumption.

Note that the "predetermined time" for reducing transmission power may be constant or may vary depending on signal strength.

Here, in a system that includes a remote control 20 that can be carried by the user and a junction unit 40 that is powered by the vehicle's onboard battery, and in which basic control begins with sending commands from the remote control 20, it is possible to reduce the transmission power consumption of the junction unit 40, thereby minimizing the power consumption of the vehicle's onboard battery.

Furthermore, for example, if the amount of information to be transmitted is large and the information is divided into multiple transmissions, it is advisable to configure the first transmission to be performed with high transmission power, and adjust the second and subsequent transmissions based on the radio wave strength of the first transmission. In this way, transmission power can be optimized. In this case, the battery life of the remote control 20 can be extended, and the frequency with which the user needs to change the battery can be minimized.

Also, for example, in the case of car security, when a sensor detects that some kind of trouble has occurred in the car, a signal can be sent from the in-vehicle device, which is a fixed device, to the remote control, even if no command is sent from the remote control. In this way, when a user who has learned that the car security is activated operates the remote control to disable the car security, the transmission power of the remote control's transmission signal can be reduced based on the radio wave strength of the signal previously received from the in-vehicle device, minimizing power consumption in the remote control's built-in battery and minimizing the frequency with which the user has to replace the battery.

Furthermore, it is preferable to configure the system so that, for example, the remote control 20 can send a signal to the junction unit 40 to set up the system. In this way, the remote control 20 can send a setting start command, and based on the radio wave strength of the response signal returned from the junction unit 40, the transmission power of the signal from the remote control 20 can be reduced, minimizing power consumption in the battery 34 built into the remote control 20 and minimizing the frequency with which the user needs to replace the battery.

A user carrying the remote control 20 may move after receiving a signal in the last communication in the system. Therefore, if the transmission power of the remote control 20 or junction unit 40 is reduced after a predetermined time (one minute in this embodiment) has elapsed, the distance between the remote control 20 and the junction unit 40 may become too great, resulting in insufficient radio wave strength and making it impossible to operate the device's functions remotely via wireless communication over long distances. Therefore, it is recommended that the transmission power be reduced within a predetermined time and that the transmission power be maintained after the predetermined time has elapsed. This allows the device's functions to be operated remotely via wireless communication over long distances, while also extending battery life. This minimizes the frequency with which the user has to perform tedious tasks such as battery replacement.

Furthermore, the "maintain at least transmission power" configuration may be a configuration that maintains transmission power or a configuration that increases transmission power. As in this embodiment, if the strength of the signal received in the last communication is less than -80 dBm or if transmission is initiated one minute after the signal in the last communication is received, it is preferable to maintain the transmission power at least at the transmission power level of the last communication. This prevents communication from being terminated due to a reduction in transmission power, ensuring communication stability. This allows the user to operate the device's functions by remote control using wireless communication over long distances without any inconvenience, even if the strength of the signal received in the last communication was weak or a predetermined time has passed since the previous communication.

If the "predetermined time" for reducing transmission power is changed depending on the signal strength, it is recommended that the greater the signal strength, the shorter the predetermined time, and the weaker the signal strength, the longer the predetermined time. However, if the signal strength is below the predetermined value, the transmission power should at least be maintained.

In the configuration of this embodiment, for example, if communication is not possible with the transmission power lowered, the transmission power is increased, and if communication is still not possible, the transmission power is increased further. When communication is not possible with the transmission power lowered, the transmission power is increased in stages or continuously, and it is particularly preferable to increase the power directly to the maximum. This provides the user with the benefit of minimizing power consumption.

In the configuration of this embodiment, the transmission power settings of the remote control 20 and junction unit 40 may be configured to be maximum under normal conditions and then automatically reduced, or may be configured to be set by the user by operating the remote control 20 or by setting a dip switch on the junction unit 40. The display 24 of the remote control 20 may also be configured to display the transmission power. This allows the user to check the transmission power. It is also advisable to configure the display 24 of the remote control 20 to display the strength of the received radio waves. This allows the user to use the remote control 20 while checking whether communication is possible based on the displayed radio wave strength.

In this embodiment, the transmission bit rate for transmitting the signal is increased if the signal strength information received in the last communication between the remote control 20 and the junction unit 40 is -80 dBm or higher and the transmission is within one minute of receiving the signal in the last communication; however, if the signal strength is less than -80 dBm or the transmission is within one minute of receiving the signal in the last communication, the transmission bit rate is maintained at least at the transmission bit rate of the last communication.

This allows the user to optimize the transmission bit rate while ensuring reliable signal transmission and reception in the system. For example, if the signal strength received by the device in the last communication is stronger than necessary, the next transmitted signal strength can be reduced. Because the remote control 20 is portable, even if the signal strength received by the device is stronger than necessary, the distance between the remote control 20 and the junction unit 40 may increase over time as the user moves. In this way, if the transmission bit rate for the next communication can be adjusted based on the signal strength received by the device in the last communication, it is possible to use time as an index to estimate the change in the distance between the remote control 20 and the junction unit 40 and adjust the rate based on this estimation. This embodiment's configuration increases the transmission bit rate not only when the signal strength received in the last communication is -80 dBm or greater, but also when the next signal is transmitted within one minute of receiving the signal in the last communication. Furthermore, this embodiment's configuration maintains at least the transmission bit rate when the signal strength is less than -80 dBm or when transmission occurs one minute after receiving the signal in the last communication. This allows the user to operate the device's functions remotely over long distances using wireless communication, while also reducing transmission power consumption. Furthermore, for remote controls 20 that use a battery 34 as a power source, battery life can be extended, eliminating the need for frequent battery replacement.

Here, the "predetermined time" for increasing the transmission bit rate, defined as "one minute," can be set based on the estimated distance at which communication between the remote control 20 and the junction unit 40 is established even if the distance between them increases, and the assumed speed at which the distance between the remote control 20 and the junction unit 40 increases, for example, when increasing the transmission bit rate of the next signal transmission above the transmission bit rate at the time of the last communication. Assuming a case in which the distance between the remote control 20 and the junction unit 40 increases as the user moves on foot, the "predetermined time" can be set based on the relationship between the average walking speed of an average adult, the estimated distance at which communication between the remote control 20 and the junction unit 40 is established after the increase in the transmission bit rate is reduced, and the expected reduction in communication distance due to the increase in the transmission bit rate. In this way, by using time as an index to estimate changes in the distance between the remote control 20 and the junction unit 40, setting a "predetermined time" based on this estimated result, and using this predetermined time as one of the criteria for increasing the transmission bit rate, the user can operate the device's functions over long distances by remote control using wireless communication without any inconvenience, even when control is performed to increase the transmission bit rate.

The "predetermined time" for increasing the transmission bit rate may be constant or may vary depending on the signal strength.

Furthermore, the configuration for "maintaining at least the transmission bit rate" may be a configuration for maintaining the transmission bit rate, or a configuration for lowering the transmission bit rate. As in this embodiment, if the strength of the signal received in the last communication is less than -80 dBm or if transmission is initiated one minute after the signal was received in the last communication, the transmission bit rate should be maintained at least at the transmission bit rate of the last communication. This prevents communication from being disrupted by increasing the transmission bit rate, ensuring communication stability. This allows the user to operate the device's functions over long distances by remote control using wireless communication without any inconvenience, even if the strength of the signal received in the last communication was weak or a predetermined amount of time has passed since the previous communication.

For a given bandwidth in a communications system, the transmission bit rate, sensitivity (travel distance), and transmission power are inversely proportional to each other. In other words, in the system of the present invention, increasing the transmission bit rate reduces the distance (decreased sensitivity) for the same bandwidth and transmission power, shortening the distance at which device functions can be activated by remote control using wireless communication. However, this shortens the transmission time and enables faster system communication operations. Here, if the received signal strength is high, communication is possible even with low sensitivity, and therefore communication is possible even if the transmission bit rate is increased. Therefore, in this embodiment, the stronger the received radio waves, the greater the transmission bit rate should be increased. In this way, a user can obtain a system that allows them to quickly activate one of the functions from either the remote control 20 or the junction unit 40 when transmitting a signal to activate the other function from the other.

In this embodiment, multiple spreading rates can be set in spread spectrum wireless communication, and it is preferable to change the spreading rate for each packet transmission.

This allows users to build wireless systems that are extremely difficult to intercept.

The "changing of the spreading factor" may be configured to be performed in a predetermined pattern. The "predetermined pattern" of the "changing of the spreading factor" may be configured to be random or in a predetermined order. Here, in the system of the present invention, the higher the spreading factor, the longer the distance at which the device's functions can be activated by remote control using wireless communication. Therefore, it is particularly preferable to configure the system to use the maximum spreading factor and the spreading factor one level lower. In such a configuration, the pattern for changing the spreading factor may be configured to alternate between the maximum spreading factor and the spreading factor one level lower in a predetermined pattern. In this way, it becomes possible to activate the device's functions by remote control using wireless communication over a long distance and in a manner that is difficult to intercept.

In this embodiment, the spreading factor is changed every time a packet is transmitted, but any other configuration is acceptable, such as every time a packet with a predetermined amount of data is transmitted, or every time a predetermined amount of time has passed.

The "spreading factor" may be, for example, the ratio (C/B) of the spreading code speed (also called the "chip rate"; C) to the transmission bit rate (B).

In this embodiment, it is preferable to be able to communicate by switching the channel used for communication.

By doing this, communication is carried out while the frequency band allocated for use in communication is switched, allowing users to obtain a system that is less susceptible to interference between spread spectrum communication systems. In this case, the receiving and transmitting sides switch channels in sync. For example, if the band used for wireless communication is the 920 MHz band, it would be desirable to configure the system to switch between six channels with center frequencies of 922.4 MHz, 922.6 MHz, 922.8 MHz, 923.0 MHz, 923.2 MHz, and 923.4 MHz. However, channels other than these may also be used.

Spread spectrum systems, particularly LoRa systems, allow for significantly longer communication distances than FSK systems. Therefore, when using a communication system with a long communication distance, such as LoRa systems, there is a high possibility of interference occurring due to other users' communications interrupting the communication range. Therefore, when using spread spectrum systems, particularly LoRa systems, it is preferable to suppress interference by appropriately switching the channel used for communication. This allows users to communicate stably without being affected by other users' devices that use spread spectrum communication nearby.

In this embodiment, the system includes a vehicle control device 68 that starts the engine based on a vehicle start signal, and an immobilizer 66 that can send a start permission signal to the vehicle control device 68 to allow the engine 70 to start. The system receives a personal identification code transmitted from a genuine key 62a that is portable and capable of transmitting a personal identification code, and indirectly transmits the personal identification code to the vehicle 60 to which the immobilizer 66 transmits the start permission signal based on the received personal identification code and a reference code provided in the immobilizer 66. The system is configured to include a remote control 20 and a junction unit 40. The wireless communication can be selected between a spread spectrum method and a communication method other than the spread spectrum method, and the remote control 20, which can be carried by the user, can receive a secret code from the genuine key 62a and can transmit a signal including a conversion code converted from the received secret code and a start instruction signal to the junction unit 40. The junction unit 40 is mounted on the automobile 60 and can convert the received conversion code into a secret code and transmit the converted secret code to the immobilizer 66, and can transmit a vehicle start signal to the vehicle control device 68 upon receiving a start instruction signal.

In this way, in a vehicle 60 equipped with an immobilizer 66, the user can start the engine 70 using the portable remote control 20 without leaving the original key 62a inside the vehicle, while keeping it with them. Generally, due to security concerns, for example, the original key 62a and the immobilizer 66 cannot send or receive a pin code unless they are in close proximity, and starting the engine 70 is not permitted. However, in this way, even if the original key 62a and the immobilizer 66 are far apart, the pin code sent from the original key 62a is relayed between the user's portable remote control 20 and the junction unit 40 installed in the vehicle 60, and can be received by the immobilizer 66, allowing starting of the engine 70.

In this embodiment, the "indirect transmission" of the PIN code is achieved by having the remote control 20 receive the PIN code from the genuine key 62a, convert the PIN code into a different conversion code, and transmit it to the junction unit 40, which then converts the received conversion code back into the original PIN code before transmitting it to the immobilizer 66.

In this embodiment, the junction unit 40 is "mounted on a vehicle" as a so-called retrofit to a sold vehicle, but it may also be attached to the vehicle by the automobile manufacturer when the vehicle is manufactured.

In this embodiment, the start instruction signal sent by the remote control 20 is issued by the user operating the operation button 26.

In this embodiment, the wireless communication between the remote control 20 and the junction unit 40 can be selected between LoRa and FSK. Therefore, even if it is difficult to permit starting of the engine 70 using one of the methods, the likelihood of permitting starting of the engine 70 can be increased. The "communication method selection" may be performed in any manner, such as via switches (e.g., dip switches) or a control device provided on the junction unit 40, and particularly preferably via the portable remote control 20. Furthermore, the communication method may be selected based on the operation of an operating unit provided on the remote control 20 or another device. The operating unit may be, for example, a slider, or may be a slider displayed on a display screen provided on the remote control 20 or another device.

It is desirable to configure the system so that the user can select between a mode in which the PIN code transmitted from the genuine key 62a is relayed by the remote control 20 and junction unit 40 (hereinafter referred to as "relay mode"), and a mode in which it is not relayed (hereinafter referred to as "non-relay mode"). In this way, users and retailers can simply prepare one system equipped with the remote control 20 and junction unit 40 to support both vehicle models equipped with an immobilizer 66 and vehicle models not equipped with an immobilizer 66, and can also accommodate users of vehicle models equipped with an immobilizer 66 who are willing to leave the genuine key 26a inside the vehicle 60. The selection between "relay mode" and "non-relay mode" can be made by, for example, providing a switch on the in-vehicle device and using this switch to make the selection.

When "Relay Mode" is selected, it is recommended that the transmitting side's wireless communication be configured to use the FSK continuous mode. "Continuous Mode" is a mode in which the DIO2/DATA pin level is transmitted as is (without going through a FIFO).

When the "non-relay mode" is selected, it is preferable to select either the "long distance mode" or the "short distance mode." In this embodiment, the "long distance mode" selects the packet mode of the LoRa system for wireless communication on the transmitting side. The "packet mode" is a mode in which the SPI (Serial
It is preferable to configure the device so that data provided by the FIFO is sent as packets via a FIFO.

In this embodiment, "short-distance mode" sets the transmitting side's wireless communication to the LoRa system with a higher transmission bit rate than in long-distance communication mode, but it may also be configured so that the transmitting side's wireless communication is in FSK packet mode.

The components of this embodiment may be combined in any desired manner. Furthermore, the components described in the Summary of the Invention may be combined in any desired manner with the components of this embodiment.

10 Engine starter 20 Remote control 22 Case 24 Display unit 24a Horizontal bar 24b Engine start animation 26 Operation buttons 26a Start button 26b Engine button 26c Stop button 28 Antenna 30 Wireless communication circuit 32 Control unit 34 Battery 36 Cable 40 Junction unit 42 First connector 42a Plug 44 Second connector 46 Third connector 48 Fourth connector 50 Wireless communication circuit 52 Control unit 54 Temperature sensor 56 Antenna unit 60 Automobile 62 Key 62a Genuine key 64 Keyhole 66 Immobilizer 68 Vehicle control device 70 Engine

Claims (5)

A first device and a second device capable of wireless communication are provided,
at least one of the first device and the second device is portable by a user, and the signal transmitted by the one device includes a signal for activating a function of the other of the first device or the second device;
reducing transmission power when a strength of a signal received in a last communication between the first device and the second device is equal to or greater than a predetermined value and transmission is performed within a first predetermined time period from reception of the signal in the last communication;
A system characterized by maintaining the transmission power at least at the transmission power at the time of the last communication when the signal strength is less than the predetermined value or when transmitting after the first predetermined time has elapsed since receiving the signal in the last communication. The system described in claim 1 is characterized in that it has a function of changing the first predetermined time depending on the signal strength. increasing a transmission bit rate for transmitting a signal when the strength of the signal received in the last communication between the first device and the second device is equal to or greater than a predetermined value and the signal is transmitted within a second predetermined time period from the reception of the signal in the last communication;
The system according to claim 1 or 2, characterized in that when the signal strength is less than the predetermined value or when transmission is performed after the second predetermined time has elapsed since reception of the signal in the last communication, the transmission bit rate is maintained at least at the transmission bit rate at the time of the last communication. The first device in the system according to any one of claims 1 to 3 . The second device in the system according to any one of claims 1 to 3 .