JP3139422B2 - Wireless communication equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a parent-child telephone attached to a facsimile apparatus or used independently, and relates to a radio communication device in which a parent device and a child device are wirelessly connected.

[0002]

2. Description of the Related Art In recent years, wireless communication devices called cordless telephones and the like, in which a master unit and a slave unit are not connected by wire but are connected wirelessly, are widely used in homes and the like. Some have such a cordless telephone. Such a wireless communication device is very convenient because it allows a child device to be carried in a dwelling unit or an arbitrary place near a dwelling unit and to communicate with a base unit and a public line via the base unit.

[0003] Such a wireless communication device does not require a user to obtain a wireless license, and anyone can use it freely. Therefore, in order to avoid radio interference with other communication devices that use radio waves, the frequency band and output power that can be used for wireless communication between the parent and child devices are severely limited. For example, the frequency band adopts the MCA (multi-channel access) method, the control channel used for line connection is 2CH, and the communication channel for communication is 87 channels.
CH is prepared, and it is obliged to use these channels for communication between the parent and child units of all cordless telephones. When starting communication, the cordless telephone uses carrier sense (available channels). (Scanning), and a channel not used at that time, that is, a channel in which no carrier is detected is used to avoid crosstalk and noise.

At the time of the carrier sense, noise inherent in the radio communication device, for example, in the case of a cordless telephone attached to a facsimile machine, the generated noise can be predicted in advance, and thus becomes such noise. Channels with the same frequency as radio waves are used at the manufacturing stage by manufacturers.
It can be excluded from the target of available channels.

However, in such a conventional wireless communication device, noise due to the installation environment of the device, for example, noise generated from nearby electronic devices such as a copying machine, a personal computer, a microwave oven, etc., at the maker stage. It was not possible to predict, and therefore, it was not possible to previously prohibit use of a channel having the same frequency as the noise radio wave.

[0006] In this case, if all the channels on which the carriers are detected are prohibited, the use of even the channels that happen to be used for the normal communication between the parent and child units of the nearby wireless communication equipment is prohibited. As a result, usable channels are limited.

[0007]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above circumstances, and has a parent-child device that is less affected by noise and that does not excessively limit available channels. It is an object of the present invention to provide a wireless communication device capable of performing high-quality communication between devices.

[0008]

According to a first aspect of the present invention, there is provided a radio communication apparatus which is proposed to achieve the above object by combining a pair of a specific parent carrier and a specific slave carrier. 2. Description of the Related Art In a wireless communication device that enables two-way simultaneous communication by transmitting and receiving wireless signals constituting one channel, carrier sense is performed for all available channels, and the same channel is configured in this carrier sense. If it is detected that only one of the master carrier and the slave carrier has a carrier, the channel is set as a prohibited channel and excluded from the next carrier sense, while the same channel is If both the parent carrier and the child carrier are configured, the channel is prohibited. Without setting the tunnel, it is characterized in that the target of the next carrier sense.

[0009] Here, the carrier refers to a radio signal of a high frequency that carries a signal for wireless communication, and the channel refers to a parent device permitted to be used by a communication device in order to perform two-way simultaneous communication. Carrier transmission carrier frequency (parent unit channel), or child unit transmission carrier frequency (child unit channel), or a pair of parent unit channel and child unit channel that must be used simultaneously as a pair. Sense refers to detecting the presence or absence of a carrier already used by another communication device and finding an available channel on which no carrier is detected.

[0010] The wireless communication device according to claim 2 is
In a wireless communication device that enables two-way simultaneous communication by transmitting and receiving a wireless signal forming one channel by a combination of a pair of a specific base unit transmission carrier and a specific slave unit transmission carrier, Carrier sense is performed a plurality of times for a channel, and, in this plurality of times of carrier sense, when it is detected that only one of the master transmission carrier and the slave transmission carrier configuring the same channel has a carrier, While setting the channel as a prohibited channel and excluding it from the target of the next carrier sense, if both the master transmission carrier and the child transmission carrier constituting the same channel are detected, the channel is set to the prohibited channel. It is characterized in that the channel is not set as a prohibited channel and is targeted for the next carrier sense.

Here, the wireless communication device according to the present invention includes:
It includes a cordless telephone used independently and independently, a telephone attached to a facsimile apparatus, a telephone attached to a computer, and the like.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an example of the internal configuration of the wireless communication device of the present invention. here,
An example of a facsimile machine with a cordless telephone is described, but the present invention is not limited to this.

This wireless communication device A includes a base unit D1 and a handset D2 of a cordless telephone separately from a facsimile machine F for transmitting and receiving image data, and is controlled by a line control unit 27 having a changeover switch. One telephone line L can be switched and used between the facsimile machine F side and the master machine D1 side, and the slave machine D2 can be cordlessly connected to the handset 2 of the facsimile machine F via the master machine D1.
9 and an external call.

The cordless telephone handset D2 has a storage unit 2
Wireless transmission / reception unit 3 for wireless transmission / reception to / from master unit D1, microphone M and speaker SP
A communication circuit 4 including a display unit 6 including a liquid crystal display,
It is also connected to a key operation unit 5 provided with a numeric keypad and various other operation keys necessary for making a telephone call, and a wireless transmission / reception unit 3, and receives a radio wave before transmitting a call to the base unit D1 and the like. It is connected to a carrier sense circuit 7 for performing sensing.

The storage unit 2 stores a channel / carrier table, which will be described later, and a program for the signal processing unit 1 to perform necessary control. Master unit D1 is slave unit D2
Similarly to the above, the signal processing unit 10 including the storage unit 11 includes a wireless transmission / reception unit 12, a communication circuit 13, a display unit 14, a key operation unit 15, a carrier sense circuit 16, and a hook switch 17.

When a call from the slave unit D2 is detected,
The hook switch 17 enters an on-hook state. The facsimile machine F has a modem 2 for transmitting and receiving image data on a facsimile side line L2 connected to the line control unit 27.
6, a signal processing unit 20, an image reading unit 21, a storage unit 22, a print output unit 23, a key operation unit 24, and a display unit 25 are connected to perform a general facsimile operation. The signal processing unit 20 is connected to the signal processing unit 10 of the master unit D1, and also controls the processing of the entire device. Also, the facsimile machine F has a three-point switch 2 for switching the connection between the telephone handset 29, the line L and the master unit D1.
8 are provided.

Next, the operation of the wireless communication device A will be described. FIG. 2 is a diagram showing a basic procedure of a normal cordless telephone call between a parent device and a child device. Here, a case where a call is made from the master unit is shown, but the same applies to a case where a call is made from the slave unit. When a call is made from the base unit D1 and a connection request is made, the carrier sense circuit 16 performs carrier sense of the control channel and the communication channel, and specifies the communication channel to be used if the control channel is available. A call code is sent out and a connection request is made (procedure (1)). In response to this, in the slave unit D2, the calling code is collated, the carrier sense circuit 7 performs carrier sense of the control / designated communication channel, and confirms the vacancy of the channel.
A response of connection OK is made (procedure (2)).

In response, a call is made using the designated call channel (procedure (3)). Thereafter, when the conversation ends, the on-hook signal of the master unit is transmitted as an end notification (procedure (4)), and the slave unit D2 responds thereto,
The communication channel is disconnected (procedure (5)), and the process ends. FIG. 3 is a table showing an example of the channel table used in the present invention.

This table shows a pair of carrier frequencies for a master / slave unit of a control channel 2CH and a communication channel channel 87CH which can be used in the MCA system which is a communication standard between the master and slave units of the wireless communication device of the present invention, and The two carrier flags correspond to each other. In the MCA method, as described above, a total of 89 CHs can be used, a 380 MHz band radio wave is specified as the master transmission carrier, a 250 MHz band radio wave is specified as the slave transmission carrier, and the channel interval is 12.5 KHz. As a result, the difference between the frequencies of the carrier for transmitting the master unit and the carrier for transmitting the slave unit is always 126.
35 MHz.

Also, in the table, channels 46 and 89
Is a control channel, and the others are traffic channels. The carrier flag indicates whether the carrier is prohibited (indicated by "x" in the table) or not (indicated by "o" in the table). Steps 100 to 104 in FIG.
5 is a flowchart illustrating an example of a basic operation procedure of setting a use-prohibited channel (claim 1), which is a feature of the wireless communication device A according to the present invention.

When the installation location of the wireless communication device A is specified and the power is turned on at that location, carrier sensing is started. This carrier sense is performed with reference to the channel table for all carrier frequencies that can be used by the wireless communication device. If a carrier is detected and the carrier level (voltage level) is equal to or higher than a predetermined threshold, the carrier sense is performed. , It is determined that there is a carrier, and a channel having that carrier is set as a prohibited channel. As a result, a flag is set in the channel table (for example, FIG.
Channel 3 flag), the channel having that carrier is regarded as a prohibited channel, and is excluded from the target of the next carrier sense.

In this way, scanning is performed for all carriers in the channel table, and the process is terminated. By doing so, the carrier sense at the time of power-on
The channel in which the carrier is detected, that is, the channel in which the noise is detected is excluded from the target of the carrier sense from the next time, so the channel in which the noise is likely to occur is not permitted to be used, High quality communication is possible.

The setting of the use prohibition channel according to the present invention is applied to both the speech channel and the control channel, but the control channel (channels 46 and 8 in FIG. 3) is used.
9) may be excluded from the target of the use prohibition channel setting. When the power is turned on, the use prohibition channel setting is performed by performing carrier sense a plurality of times at a predetermined time interval, for example, every 5 minutes, and as a result, setting a carrier frequently used to be used as a prohibited carrier. Further effects are exhibited (claim 2).

This is because a radio signal detected frequently in a plurality of carrier senses can be regarded as having a high degree of noise as a noise even after the start of a call or a call, and a channel having a carrier of that frequency is used. This is because the signal is excluded from the original target of carrier sense, so that the possibility of being affected by noise is further reduced and the quality of communication is improved.

In the above description, the case in which the use prohibited channel is set when the power is turned on has been described. However, in the wireless communication device of the present invention, not only when the power is turned on, but also
It is also possible to repeat the use prohibition channel setting every time a certain period elapses, and in such a case, the use prohibition setting can be updated according to a change in the environment.

Steps 200 to 208 in FIG. 5 are flowcharts showing an example of a basic operation procedure for canceling the setting of the prohibited channel, which is a feature of the wireless communication device according to the present invention (claim 3). Steps 200 to 204 are the same as steps 100 to 104, and a description thereof will be omitted. As a result of this processing, it is assumed that the flag of the channel table is set as shown in FIG.

Thereafter, the channel table is scanned to check whether both carriers of the channel pair, that is, both the carrier of the slave unit and the flag of the carrier of the master unit, are set. If so, all the flags of the slave carrier and the master carrier are reset (arrows in FIG. 3). This is performed for all the channels, and the process ends.

As a result, for example, in FIG. 3, the carrier flags of both channels 2 are all set to “○”, and are subject to carrier sensing and can be used. Such processing is performed when both the carrier for transmission of the slave unit and the carrier for transmission of the master unit are detected, and when the normal communication is normally performed between the master and slave units of another wireless communication device. Is happened to be caught, and after the communication in use is completed, it can be determined that the channel is likely to be used as a normal communication channel, so that the channel is left as an available channel. .

[0029] In this way, a channel that has been used for normal communication in another wireless communication device is not unnecessarily set to be prohibited, and excessive use of the channel can be avoided. In addition to the method described above, when the frequency is detected by the carrier sense, it is determined whether or not the flag of the paired carrier is already set, and the flag is set in both sides. If so, there is a method of resetting all the flags of the channel.

[0030]

As will be understood from the above description, according to the wireless communication device of the first aspect of the present invention, when carrier sense is performed for all channels usable as a wireless communication device, Channels that have been detected as having only one of the parent transmission carrier and the child transmission carrier that make up the same channel as a pair are set as prohibited channels and excluded from the next carrier sense target. Channels in which both the parent transmission carrier and the child transmission carrier constituting the same channel as a pair are detected are not excluded from the next carrier sense, and the line connection procedure can be executed. Therefore, a channel having a high possibility of noise is excluded from the use target, high-quality communication is secured, and it is possible to prevent a channel usable for normal communication from being set to the use prohibition.

According to the wireless communication device of the second aspect of the present invention, carrier sense is performed a plurality of times for all the channels usable as the wireless communication device, and the same processing as in the first aspect is performed. Therefore, the same effect as the first aspect can be obtained. In addition, a radio signal that is frequently detected in a plurality of times of carrier sense can be regarded as having a high degree of noise as a noise even after the start of a call or a call. Can be excluded from the target of the carrier sense, and the possibility of being affected by noise is reduced, so that the communication quality can be further improved.

[0032]

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of an internal configuration of a wireless communication device according to the present invention.

FIG. 2 is a diagram showing a basic procedure of a normal cordless telephone call between a parent device and a child device.

FIG. 3 is a table showing an example of a channel table used in the present invention.

FIG. 4 is a flowchart illustrating an example of a basic operation procedure of setting a use-prohibited channel, which is a feature of the wireless communication device according to the present invention.

FIG. 5 is a flowchart illustrating an example of a basic operation procedure of canceling use-prohibited channel setting, which is a feature of the wireless communication device according to the present invention.

[Explanation of symbols]

 A wireless communication device D1 master unit D2 slave unit 7, 16 carrier sense circuit 1, 10 signal processing unit 2, 11 storage unit

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04Q ^7/ 00-7/38

Claims (2)

(57) [Claims] 1. A wireless communication device which enables two-way simultaneous communication by transmitting and receiving a radio signal forming one channel by a combination of a pair of a specific base unit transmission carrier and a specific slave unit transmission carrier, Carrier sense is performed for all available channels, and if it is detected that only one of the parent carrier and the child carrier constituting the same channel has a carrier, the channel is set as a prohibited channel. Then, while excluding from the target of the next carrier sense, if both the master transmission carrier and the child transmission carrier constituting the same channel are detected, the channel is not set as the prohibited channel. A wireless communication device to be subjected to the next carrier sense. 2. A wireless communication device which enables two-way simultaneous communication by transmitting and receiving a radio signal constituting one channel by a combination of a specific base unit transmission carrier and a specific slave unit transmission carrier. Carrier sense is performed multiple times for all the channels, and if it is detected that only one of the parent carrier and the slave carrier constituting the same channel has a carrier in the multiple carrier senses, , The channel is set as a prohibited channel and excluded from the target of the next carrier sense, and if both the master transmission carrier and the child transmission carrier constituting the same channel are detected, the Wireless communication, which is not set as a prohibited channel and is targeted for the next carrier sense. Communication equipment.