JP5653402B2 - In-vehicle DSRC / VICS transmission / reception device and transmission / reception data transmission method used in in-vehicle DSRC / VICS transmission / reception device - Google Patents

Description

  The present invention relates to an in-vehicle transmission / reception apparatus that processes road traffic information transmitted from a beacon installed on a road, and in particular, an in-vehicle DSRC / VICS transmission / reception apparatus that supports both a DSRC service and a service using an optical beacon of VICS, and The present invention relates to a transmission / reception data transmission method used in an in-vehicle DSRC / VICS transmission / reception device.

VICS (registered trademark) (Vehicle Information and Communication System) is a road traffic information communication system that provides traffic information such as traffic congestion and traffic control to drivers in real time, thereby reducing traffic congestion and traffic accidents. It is a road traffic information service for the purpose of improving.

  The VICS information is transmitted from a beacon installed on the road toward the vehicle-mounted antenna, A / D converted by the VICS transmission / reception device, and then output to a car navigation system (hereinafter abbreviated as “car navigation”). The car navigation system displays this VICS information on the display unit of the car navigation system to support the driver's comfortable and smooth driving.

  The following two types of beacon communication methods in VICS are mainly used.

  The first uses radio waves. A radio beacon installed on a highway carries a 64 Kbps VICS signal on a 2.4 GHz radio wave and transmits it to the antenna of the automobile.

  The second uses infrared rays. An optical beacon installed on a general road carries a VICS signal having a reception of 1024 Kbps and a transmission of 64 Kbps on an infrared ray and transmits the signal toward an automobile antenna.

  Radio beacons and optical beacons are installed in different locations, and both radio and optical antennas are required to use both radio and optical beacons depending on the location of the beacons. .

  For this reason, the conventional VICS transmission / reception apparatus includes both antennas for radio waves and light, and a method is adopted in which analog signals of received radio waves and light are A / D converted by a common signal processing circuit. (For example, refer to Patent Document 1).

  Note that there is a DSSS (Driving Safety Support Systems: Safe Driving Support System) as a service using the VICS optical beacon. DSSS is a service that uses the locality and bidirectionality of optical beacons, and predicts danger by using the road conditions ahead and the location / speed information of the car, and alerts the driver.

On the other hand, as a new road traffic information service, there is DSRC (registered trademark) (Dedicated Short-Range Communication ) started in 2011.

  DSRC replaces the services provided by the above-mentioned VICS radio beacons. By using the same high frequency radio waves of 5.8 GHz as ETC, road traffic information services including ETC are faster and larger than radio beacons. It is provided to the capacity (for example, see Patent Document 2).

  Radio waves are used for the DSRC beacon communication method. A DSRC beacon installed on a highway carries a DSRC signal of 1024 Kbps or 4096 Kbps on a radio wave of 5.8 GHz and transmits the signal to an automobile antenna.

  In order to use both DSRC and VICS services, both transmitting and receiving apparatuses are required. A car navigation system compatible with both services includes DSRC and VICS I / Fs, and can connect both the DSRC transmission / reception device and the VICS transmission / reception device (see, for example, Non-Patent Document 1).

  Services provided by DSRC include services provided by VICS radio wave beacons, and further include functions such as ETC. Therefore, when the DSRC service can be used, the VICS radio beacon service is actually unnecessary, and the VICS radio beacon is not newly installed in the future.

JP 2002-174522 A JP 2002-269607 A

N871L69923 1/2 12-06 Mitsubishi Electric Corporation Mitsubishi Car Navigation System NR-MZ60 Series Installation Manual Page 2

However, the prior art has the following problems.
The conventional in-vehicle DSRC / VICS transmission / reception device has a redundant configuration in which the DSRC transmission / reception device and the VICS transmission / reception device are simply combined. Specifically, it includes three antennas for DSRC, radio waves and light, and two processing circuits for DSRC and VICS. As a result, there is a problem that the configuration of the in-vehicle DSRC / VICS transmission / reception device is complicated and expensive.

  Also, the DSRC beacon and the VICS radio beacon are often provided at the same location. In such a configuration in which two transmission / reception devices are simply combined, DSRC information and VICS information are simultaneously processed by each transmission / reception device, simultaneously time-division multiplexed, and simultaneously output to the car navigation system.

  Therefore, it is a heavy load for a car navigation system to simultaneously restore and process multiplexed signals simultaneously output from the DSRC transmission / reception apparatus and the VICS transmission / reception apparatus. For this reason, it is necessary to provide a determination unit for determining which signal is preferentially processed in the car navigation system, which causes a problem that the circuit of the car navigation system is more complicated and expensive.

  In order to solve the above-mentioned problem, the DSRC transmission / reception device and the VICS transmission / reception device are not simply combined, but may be integrated without a redundant configuration. Specifically, a circuit related to a radio beacon that is not actually used is removed, and a circuit related to an optical beacon that will be used in the future is integrated into the DSRC transceiver device.

  However, when the radio wave / optical signal processing circuit is removed from the circuit related to the radio beacon, there are the following problems.

  In the conventional VICS transmission / reception apparatus, the radio wave / optical signal processing circuit performs A / D conversion on the radio wave beacon and the signal received from the optical beacon, time-division multiplex, and transmits the signal to the car navigation system using the VICS serial line.

  Therefore, when the radio wave / optical signal processing circuit is removed, time division multiplexing cannot be performed, and only one of the transmission signal and the reception signal of the optical antenna can be sent to the VICS serial communication line.

  That is, in the conventional in-vehicle DSRC / VICS transmission / reception apparatus, when the radio wave / optical signal processing circuit is removed in an attempt to integrate the DSRC transmission / reception apparatus and the VICS transmission / reception apparatus, the transmission signal and the reception signal of the optical beacon are transmitted to the DSRC signal processing circuit. For this reason, there was a problem that the signal lines for the above were insufficient.

  The present invention has been made to solve the above-described problems, and has a simple circuit configuration in which a circuit related to a radio wave beacon is removed, and is compatible with both a DSRC service and a service using a VICS optical beacon. It is an object to obtain a transmission / reception data transmission method used for a DSRC / VICS transmission / reception device and an in-vehicle DSRC / VICS transmission / reception device.

The in-vehicle DSRC / VICS transmission / reception apparatus according to the present invention receives a DSRC signal from a DSRC beacon, transmits a DSRC signal to the DSRC beacon, receives an optical reception signal from the optical beacon, and transmits an optical transmission signal to the optical beacon. The road traffic information based on each of the DSRC signal and the optical reception signal received by the antenna unit while generating and transmitting the DSRC signal and the optical transmission signal to be transmitted to the outside through the antenna unit and the antenna unit An in-vehicle DSRC / VICS transmission / reception device including a signal processing unit that generates and outputs to the outside, wherein the optical transmission signal and the optical reception signal are transmitted between the antenna unit and the signal processing unit to transmit the DSRC signal. Is transmitted through the coaxial line provided in the optical signal, and the three signals of the optical reception signal, the optical transmission signal, and the DSRC signal. However, when transmitted through the coaxial line, the antenna unit receives the optical transmission signal output from the signal processing unit by receiving the signal from the coaxial line through the first filter unit, The signal processing unit receives the signal from the coaxial line through the second filter unit, thereby receiving the DSRC signal output from the antenna unit and receiving the signal from the coaxial line through the third filter unit. Thus, the optical reception signal output from the antenna unit is received , and the first filter unit, the second filter unit, and the third filter unit use a λ / 4 short stub and an RL circuit or an RC circuit. This is realized in combination with the removal filter .

In addition, the in-vehicle DSRC / VICS transmission / reception method according to the present invention includes receiving a DSRC signal from a DSRC beacon, transmitting a DSRC signal to the DSRC beacon, receiving an optical reception signal from the optical beacon, and transmitting an optical transmission signal to the optical beacon. An antenna unit that performs transmission, generates a DSRC signal and an optical transmission signal to be transmitted to the outside through the antenna unit, transmits them to the antenna unit, and roads based on the DSRC signal and the optical reception signal received by the antenna unit A transmission / reception data transmission method used in an in-vehicle DSRC / VICS transmission / reception apparatus including a signal processing unit that generates traffic information and outputs the traffic information to an optical transmission signal and an optical reception signal for transmitting the DSRC signal Transmitting via a coaxial line provided between the antenna unit and the signal processing unit; When all three signals of the reception signal, the optical transmission signal, and the DSRC signal are transmitted through the coaxial line, the antenna unit receives the signal from the coaxial line through the first filter unit, thereby The step of receiving the optical transmission signal output from the processing unit, and the signal processing unit receives the signal from the coaxial line via the second filter unit, thereby receiving the DSRC signal output from the antenna unit. by receiving the signal through the third filter portion from the coaxial line, have a receiving a received optical signal output from the antenna unit, the first filter portion, the second filter portion and the second The filter unit 3 is used in an in-vehicle DSRC / VICS transmission / reception device characterized by combining a λ / 4 short stub and a removal filter using an RL circuit or an RC circuit. It is.

  According to the present invention, both a DSRC service and a service using an optical beacon of VICS have a simple circuit configuration in which a circuit related to a radio wave beacon is removed by superimposing a plurality of transmission / reception signals on a coaxial line and performing communication processing. And the transmission / reception data transmission method used for the in-vehicle DSRC / VICS transmission / reception device and the in-vehicle DSRC / VICS transmission / reception device can be obtained.

It is an illustration figure of the vehicle-mounted DSRC / VICS transmission / reception apparatus in Embodiment 1 of this invention. It is an illustration figure of (lambda) / 4 short stub in Embodiment 1 of this invention. It is an illustration figure different from FIG. 1 of the DSRC transmission / reception apparatus in Embodiment 1 of this invention. It is an illustration figure of the vehicle-mounted DSRC / VICS transmission / reception apparatus in Embodiment 2 of this invention. It is an illustration figure of the vehicle-mounted DSRC / VICS transmission / reception apparatus in Embodiment 3 of this invention. It is an illustration figure of the vehicle-mounted DSRC / VICS transmission / reception apparatus in Embodiment 4 of this invention. It is an illustration figure of the vehicle-mounted DSRC / VICS transmission / reception apparatus in Embodiment 5 of this invention. It is an illustration figure of the conventional vehicle-mounted DSRC / VICS transmission / reception apparatus.

  Hereinafter, preferred embodiments of a transmission / reception data transmission method used for an in-vehicle DSRC / VICS transmission / reception device and an in-vehicle DSRC / VICS transmission / reception device according to the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected and demonstrated about the part which is the same or it corresponds in each figure.

Embodiment 1 FIG.
Before describing the configuration of the first embodiment, first, the configuration of a conventional apparatus will be described with reference to the drawings. FIG. 8 is an illustration of a conventional in-vehicle DSRC / VICS transmission / reception device.

  The conventional in-vehicle DSRC / VICS transmission / reception device shown in FIG. 8 includes a car navigation system 3, a DSRC serial line 6, a VICS serial line 7, a conventional DSRC transmission / reception device 8, and a conventional VICS transmission / reception device 9.

  Here, the conventional DSRC transmission / reception apparatus 8 includes a DSRC antenna unit 1, a DSRC signal processing unit 2, and a coaxial line 5. The DSRC antenna unit 1 includes a DSRC antenna 11. The DSRC signal processing unit 2 includes a DSRC processing circuit 21 and an external I / F 24.

  The conventional VICS transceiver 9 includes a VICS antenna unit 4, a radio wave / optical signal processing circuit 91, and an external I / F 92. The VICS antenna unit 4 includes a radio wave antenna 41, an optical antenna 42, and a reception. An amplifier 44 and a transmission driver 45 are provided.

  The car navigation system 3 includes a car navigation processing circuit 31, a determination unit 32, a VICS I / F 33, and a DSRC I / F 34.

  In FIG. 8, the conventional VICS transmission / reception device 9 has a structure in which the VICS antenna unit 4 and the radio wave / optical signal processing circuit 91 are integrated, whereas the conventional DSRC transmission / reception device 8 includes the DSRC antenna unit 1. The DSRC signal processing unit 2 is separated.

  As described above, in the conventional DSRC transmission / reception device 8, the DSRC antenna unit 1 and the DSRC processing unit 2 are separated because the frequency of the DSRC radio wave is as high as 5.8 GHz and the processing load of the DSRC processing circuit 21 is large. This is because the DSRC processing circuit 21 is large and difficult to integrate with the DSRC antenna unit 1.

  Further, the conventional in-vehicle DSRC / VICS transmission / reception device has a configuration in which the conventional DSRC transmission / reception device 8 and the conventional VICS transmission / reception device 9 are simply combined. This is because there is a difference in the structure of the VICS transmission / reception apparatus 9 and it is difficult to integrate them.

  Thus, the conventional in-vehicle DSRC / VICS transmission / reception device has a redundant configuration in which the conventional DSRC transmission / reception device 8 and the conventional VICS transmission / reception device 9 are simply combined. There is a problem that the transmission / reception apparatus is complicated and expensive.

  In addition, as described in [Problems to be Solved by the Invention] above, which one is preferentially processed for multiplexed signals output simultaneously from the conventional DSRC transceiver 8 and the conventional VICS transceiver 9? Therefore, there is a problem that the car navigation system 3 is complicated and expensive.

  Next, the configuration of the first embodiment for solving the above problem will be described. FIG. 1 is an exemplary diagram of an in-vehicle DSRC / VICS transmission / reception device according to Embodiment 1 of the present invention.

  The in-vehicle DSRC / VICS transmission / reception apparatus according to the first embodiment shown in FIG. 1 includes a DSRC antenna unit 1, a DSRC signal processing unit 2, a car navigation system 3, a coaxial line 5, a DSRC serial line 6, and a VICS serial line 7. Configured.

  Here, the DSRC antenna unit 1 includes a DSRC antenna 11, an optical antenna 12, a power input 13, a reception amplifier 14, and a transmission driver 15.

  The DSRC signal processing unit 2 includes a DSRC processing circuit 21, a filter (light reception) 21b, a power source 23, an external I / F 24, and a filter (DSRC) 24a.

  The car navigation system 3 includes a car navigation processing circuit 31 and a DSRC I / F 34.

  1 is that the conventional DSRC transceiver 8 and the conventional VICS transceiver 9 in FIG. 8 are integrated. In performing such integration, the circuit configuration shown in FIG. 1 is obtained by adding the following two changes to the circuit of FIG.

  The first change is that the radio wave antenna 41, the radio wave / optical signal processing circuit 91, and the external I / F 92, which are the circuits related to the radio wave beacon in the conventional VICS transmission / reception device 9, with the colors reversed in FIG. The determination unit 32 and VICS I / F 33 in the car navigation system 3 are removed, and the optical antenna 42, the reception amplifier 44, and the transmission driver 45 are integrated into the DSRC antenna unit 1.

  The second modification is that the DSRC signal and the optical reception signal are superimposed on the coaxial line 5, the optical transmission signal is transmitted by the VICS serial line 7, and the DSRC signal and the optical signal are received when the signal is received from the coaxial line 5. A filter unit is provided in a portion that receives a signal from the coaxial line 5 so that the received signal does not interfere.

  Specifically, between the coaxial line 5 and the DSRC processing circuit 21, a filter (optical reception) 21b for removing an optical reception signal and a filter (DSRC) 24a for removing a DSRC signal are provided in parallel. Thus, there are two reasons for using a removal filter instead of a pass filter.

  The first reason is that the filter can be easily realized. For example, the pass filter needs to be configured by a resonance circuit using RLC, but the removal filter can be realized by a low-pass or high-pass filter using only RL or RC.

  As will be described later, the second reason is that the number of filters can be reduced by integrating the filters by devising the circuit configuration. A removal filter having a simple structure is suitable for integrating the filters, and the circuit configuration can be further simplified.

  However, except for the merits of the first reason and the second reason described above, it is functionally possible to use a pass filter instead of the removal filter, and in this case as well, the case where the removal filter is used is the same. The effect is obtained.

  From here, the effect of the above two changes added to FIG. 8 will be described with reference to FIG.

  First, due to the first change, a circuit related to a radio beacon that is not actually used is removed, and a circuit related to an optical beacon that will be used in the future is integrated into the DSRC transceiver device. This solves the problem that the configuration of the in-vehicle DSRC / VICS transmission / reception device is complicated and expensive.

  In addition, since there is no radio signal from the radio beacon and the signal from the optical beacon is processed by the DSRC processing circuit 21, there is no signal transmitted on the VICS I / F 33, and the car navigation determination unit 32. Is no longer needed. This solves the problem that the car navigation system 3 is complicated and expensive.

  However, as described in [Problems to be solved by the invention] above, when the radio wave / optical signal processing circuit 91 is removed, the signal line for transmitting the transmission signal and the reception signal of the optical beacon to the DSRC signal processing circuit. There is a problem that there is not enough.

  This problem is solved by the second modification. Hereinafter, the effect of the second modification will be described along the signal flow of FIG.

  First, the flow of the DSRC signal received from the DSRC beacon will be described. The DSRC signal received by the DSRC antenna 11 is transmitted to the DSRC processing circuit 21 via the coaxial line 5.

  Since the DSRC signal is a high-frequency analog signal of 5.8 GHz, the coaxial line 5 is used for the communication line connecting the DSRC antenna unit 1 and the DSRC signal processing unit 2, and the DSRC antenna unit 1 and A microstrip line is used as a communication line on the DSRC signal processing unit 2.

  A filter (optical reception) 21b provided between the coaxial line 5 and the DSRC processing circuit 21 is for removing the optical reception signal from the two signals of the DSRC signal and the optical reception signal superimposed on the coaxial line 5. Is.

  The filter (optical reception) 21b may be any filter as long as it can remove the 1024 KHz optical reception signal received by the optical antenna 12. For example, a ceramic resonator provided on the microstrip line of the DSRC processing circuit 21 for stabilizing the DSRC signal can be used as it is.

  Since this ceramic resonator has the same resonance frequency as the DSRC signal, it functions as a pass filter for the DSRC signal. In the above description, it has been stated that a removal filter is preferable to a pass filter for simplification of the circuit configuration. However, in this case, an existing ceramic resonator can be used as it is. (Optical reception) 21b does not need to be specially provided, and the circuit configuration can be simplified.

  The DSRC signal received by the DSRC antenna 11 is output on the coaxial line 5 and is superimposed on the optical reception signal. From the superimposed DSRC signal, the optical reception signal is removed by the filter (optical reception) 21 b and output to the DSRC processing circuit 21.

  Next, the flow of the optical reception signal received from the optical beacon will be described. The optical reception signal received by the optical antenna 12 is amplified by the reception amplifier 14 and superimposed on the DSRC signal on the coaxial line 5. The superposed optical reception signal is removed from the DSRC signal by the filter (DSRC) 24 a and output to the DSRC processing circuit 21.

  The filter (DSRC) 24a may be any filter as long as it can remove a 5.8 GHz DSRC signal. For example, a λ / 4 short stub provided on the coaxial line 5 for stabilizing the DSRC signal can be used as it is.

  Since the DSRC signal on the coaxial line 5 has a very high frequency, it is very sensitive to changes in the shape of the coaxial line 5. For example, simply connecting a signal line to the coaxial line 5 changes the transmission characteristics of the coaxial line 5 and attenuates or deforms the DSRC signal.

  For this reason, normally, in order to stabilize the DSRC signal on the coaxial line 5, the DSRC signal is reflected back to the coaxial line 5 at the portion where the signal line branches from the coaxial line 5 before the signal line is branched. A λ / 4 short stub is provided (not shown).

FIG. 2 is an exemplary view of a λ / 4 short stub according to Embodiment 1 of the present invention. The λ / 4 short stub can function as a DSRC signal removal filter by adjusting the stub length L when the wavelength of the DSRC signal is λ so as to satisfy the following expression (1).
L = 1 / 4λ (1)

  The filter (DSRC) 24a can also be realized by using an LC circuit. However, if a λ / 4 short stub is used, it can be realized only by adding a stub and a capacitor as shown in FIG. Can do.

In FIG. 2, the capacitor provided between the GND and the stub is for preventing the coaxial line 5 from being short-circuited. Since the impedance Z of the capacitor is calculated by the following equation (2), it can be ignored for a high frequency such as a DSRC signal, and functions as a zero resistance.
Z = 1 / ωC (2)

  Thus, by using the λ / 4 short stub as the DSRC signal removal filter, the existing λ / 4 short stub can be used as it is as the filter (DSRC) 24a. As a result, it is not necessary to provide a filter (DSRC) 24a for signal removal, and the circuit configuration can be simplified.

  The receiving amplifier 14 may be any one as long as the DSRC processing circuit 21 can obtain an amplification factor necessary for processing the optical reception signal. For example, an operational amplifier can be used.

  Note that the DSRC signal removal filter is not provided between the reception amplifier 14 and the coaxial line 5 because the reception amplifier 14 outputs the optical reception signal to the coaxial line 5 but does not input it. This is because it is not necessary to provide a filter.

  However, in order to prevent the signal on the coaxial line 5 from affecting the reception amplifier 14 and the impedance of the reception amplifier 14 from affecting the signal on the coaxial line 5, the reception amplifier 14 and the coaxial line 5 are usually connected. In the meantime, the same filter (DSRC) 24a is provided as a protective filter (not shown).

  At this time, the optical reception signal may be distorted due to the influence of the surroundings such as the impedance of the coaxial line 5. In this case, the impedance is obtained by an LC filter using an inductor (L) or a capacitor (C) not shown. Matching and waveform shaping may occur (not shown).

  Further, by providing a Zener diode between the reception amplifier 14 and the coaxial line 5, it is possible to prevent the voltage on the output side of the reception amplifier 14 from increasing unexpectedly. As a result, the receiving amplifier 14 can be protected from overvoltage.

  The DSRC processing circuit 21 inputs the DSRC signal and the optical reception signal that have been filtered from the coaxial line 5, A / D-converted, time-division multiplexed, the external I / F 24, the DSRC serial line 6, and the DSRC The data is transmitted to the car navigation processing circuit 31 of the car navigation system 3 via the I / F 34.

  A serial communication method such as USB is used for the external I / F 24, DSRC I / F 34, and DSRC serial line 6.

  The car navigation processing circuit 31 restores DSRC information and VICS information from the input time-division multiplexed signal and displays them on the display unit of the car navigation system to support the driver's comfortable and smooth driving.

  As described above, the optical reception signal is superimposed on the coaxial line 5 out of the optical reception signal and the optical transmission signal, and the optical transmission signal is transmitted using the VICS serial line 7, and further, the DSRC signal and the optical reception signal are transmitted. A filter unit is provided in a portion that receives a signal from the coaxial line so that the signal does not interfere. With such a configuration, the problem that the signal line for transmitting the transmission signal and the reception signal from the optical beacon to the DSRC processing circuit is insufficient is solved.

  Next, the flow of the DSRC signal transmitted to the DSRC beacon will be described. The signal flow in this case is opposite to that when receiving a DSRC signal from a DSRC beacon. However, the car navigation system 3 is not involved in the transmission of the DSRC signal. The DSRC transmission signal transmitted to the DSRC beacon is created not by the car navigation system 3 but by the DSRC processing circuit 21.

  The DSRC processing circuit 21 creates a DSRC signal such as ETC information, performs D / A conversion, and superimposes it on the coaxial line 5. The DSRC antenna 11 receives the DSRC signal superimposed on the coaxial line 5, puts it on the radio wave, and transmits it toward the DSRC beacon.

  At this time, transmission / reception of the DSRC signal is performed in a half-duplex manner, and the timing is instructed by the DSRC beacon. Therefore, the DSRC reception signal and the transmission signal do not interfere on the coaxial line 5.

  The reason why no optical reception signal removal filter is provided between the DSRC antenna 11 and the coaxial line 5 is that the DSRC antenna 11 itself is a kind of DSRC signal resonator and functions as a DSRC signal pass filter. This is because it is not necessary to provide an optical reception signal removal filter.

  However, in order to prevent the signal on the coaxial line 5 from affecting the DSRC antenna 11 and the impedance of the DSRC antenna 11 from affecting the signal on the coaxial line 5, normally, the DSRC antenna 11 and the coaxial line 5 In the meantime, the same filter (light receiving) 21b is provided as a protective filter (not shown).

  Next, the flow of the optical transmission signal transmitted to the optical beacon will be described. The DSRC processing circuit 21 inputs optical transmission signals such as ID information and DSSS information of the car navigation system 3 from the car navigation system 3, performs D / A conversion, and transmits them to the transmission driver 15 using the VICS serial line 7. To do. The transmission driver 15 drives the optical antenna 12 to transmit an optical transmission signal on an infrared ray toward an optical beacon.

  In this way, by using the VICS serial line 7 as a dedicated communication line for the optical transmission signal, it is not necessary to add a filter to the optical transmission signal, and a circuit to be newly added is designated as a filter (optical reception) 21b and a filter. Only (DSRC) 24a can minimize circuit changes.

  In FIG. 1, the power of the DSRC antenna unit 1 is supplied from the power source 23 of the DSRC signal processing unit 2 to the power input 13 via a power line. By sharing the power supply in this way, the power supply can be integrated into one, and the in-vehicle DSRC / VICS transmission / reception apparatus can be reduced in cost.

  As described above, according to the first embodiment, among the optical reception signal and the optical transmission signal, the optical reception signal is superimposed on the coaxial line, and the optical transmission signal is transmitted through the VICS serial line. Furthermore, a filter unit is provided in a portion that receives a signal from the coaxial line so that the DSRC signal and the optical reception signal do not interfere with each other. As a result, it is possible to obtain an in-vehicle DSRC / VICS transmission / reception apparatus compatible with both a DSRC service and a service using an optical beacon of VICS with a simple circuit configuration in which a circuit related to a radio wave beacon is removed.

  In the above description, the case where the optical reception signal is superimposed on the coaxial line 5 and the optical transmission signal is transmitted through another dedicated communication path has been described. However, the invention according to Embodiment 1 is not limited to such a case. FIG. 3 is an exemplary diagram different from FIG. 1 of the DSRC transmission / reception apparatus according to Embodiment 1 of the present invention. More specifically, it is a diagram in which the communication paths of the optical transmission signal and the optical reception signal are switched. As shown in FIG. 3, it is possible to superimpose the optical transmission signal on the coaxial line 5 and send the optical reception signal through another dedicated communication path. In this case, the same effect can be obtained.

Embodiment 2. FIG.
In the first embodiment, the DSRC signal and either one of the optical reception signal and the optical transmission signal are superimposed on the coaxial line 5, and further, the coaxial line is used so that these two signals do not interfere with each other. The method of providing the filter unit in the portion that receives the signal from 5 has been described. In the second embodiment, a method of superimposing a DSRC signal and three signals of an optical reception signal and an optical transmission signal on the coaxial line 5 will be described.

  The feature of the second embodiment is that the optical transmission signal and the reception signal are superimposed on the coaxial line 5, thereby eliminating the need for the VICS serial line 7 shown in FIG. 1 and reducing the cost of the in-vehicle DSRC / VICS transmission / reception apparatus. It is in the point that became.

  FIG. 4 is an exemplary diagram of the in-vehicle DSRC / VICS transmission / reception apparatus according to Embodiment 2 of the present invention. In order to remove the VICS serial line 7, FIG. 4 is obtained by adding the following two changes to the circuit of FIG. 1 which is a conventional in-vehicle DSRC / VICS transmission / reception device.

  The first change is that the VICS serial line 7 which is a dedicated line for the optical transmission signal in FIG. 1 is removed, and at the same time, the optical transmission signal is superimposed on the coaxial line 5.

  The second change is that the signal received from the coaxial line 5 is superimposed on the coaxial line 5 in FIG. 4 so that the three signals of the DSRC signal, the optical reception signal, and the optical transmission signal do not interfere with each other. Two signal removal filters are provided.

  Specifically, a filter (DSRC) 15 a and a filter 15 b (light reception) are provided between the coaxial line 5 and the transmission driver 15. A filter (light reception) 21b and a filter (light transmission) 21c are provided between the coaxial line 5 and the DSRC processing circuit 21, and a filter (DSRC) 24a and a filter (light transmission) 24c are provided in parallel therewith. Provided.

  The optical reception signal and the optical transmission signal transmitted / received by the optical antenna 12 are Manchester-encoded, and the frequencies of the Manchester-encoded signals are 1024 KHz and 64 KHz, respectively. In the new system, it is considered that the frequency of the transmission signal is 256 KHz.

  Therefore, in order to prevent interference between the optical reception signal and the optical transmission signal, the filter (optical reception) 15b may be any filter as long as it can remove the 1024 KHz optical reception signal. For example, a low-pass filter of about 400 KHz configured with an LC circuit can be used.

  In this case, since the filter (optical reception) 15b can also remove a 5.8 GHz DSRC signal, the filter (DSRC) 15a can be integrated into the filter (optical reception) 15b, and the circuit configuration can be further simplified.

  The filter (optical transmission) 24c may be any filter as long as it can remove optical transmission signals of 64 KHz and 256 KHz. For example, a high-pass filter of about 400 Hz configured with an LC circuit can be used.

  The same ceramic resonator as the filter (light receiving) 21b can be used for the filter (light transmitting) 21c. This is because the ceramic resonator functions as both an optical reception signal elimination filter and an optical transmission signal elimination filter. Therefore, these two filters can be integrated into one and the circuit configuration can be simplified.

  Note that there is a line between the coaxial line 5 and the DSRC processing circuit 21 that is not provided with a removal filter, because this is a line for an optical transmission signal and no signal is input from the coaxial line 5, This is because it is not necessary to provide a removal filter.

  However, in order to prevent the signal on the coaxial line 5 from affecting the DSRC processing circuit 21 and the impedance of the DSRC processing circuit 21 from affecting the signal on the coaxial line 5, the transmission line is usually connected to the coaxial line 5. The same filter unit provided between the containers 15 is provided as a protective filter (not shown).

  Further, as the protection filter of the DSRC antenna 11, the same filter (light reception) 21b and filter (light transmission) 21c provided in parallel between the coaxial line 5 and the DSRC processing circuit 21 can be used (not shown). ).

  Further, as the protection filter of the reception amplifier 14, the same filter (DSRC) 24a and filter (optical transmission) 24c provided in parallel between the coaxial line 5 and the DSRC processing circuit 21 can be used (not shown). .

  Thus, by superimposing the optical reception signal and the optical transmission signal on the coaxial line 5, the VICS serial line 7 becomes unnecessary, and the cost of the in-vehicle DSRC / VICS transmission / reception apparatus can be reduced. In particular, the effect can be expected when cost reduction is given priority over the effort of changing the circuit.

  As described above, according to the second embodiment, the three signals of the DSRC signal, the optical reception signal, and the optical transmission signal are superimposed on the coaxial line. Further, a filter unit is provided in a portion that receives signals from the coaxial line so that these three signals do not interfere with each other. As a result, it is possible to obtain an in-vehicle DSRC / VICS transmission / reception apparatus that supports both the DSRC service and the service using the VICS optical beacon with a simpler circuit configuration from which the VICS serial line is removed.

Embodiment 3 FIG.
In the second embodiment, the three signals of the DSRC signal, the optical reception signal, and the optical transmission signal are superposed on the coaxial line 5, and further, the signals are transmitted from the coaxial line 5 so that these three signals do not interfere with each other. The method of providing the filter unit in the receiving part has been described. In the third embodiment, a method of further superimposing the power signal on the coaxial line 5 will be described.

  The feature of the third embodiment is that the power signal is superimposed on the coaxial line 5 so that the power line between the power source 13 and the power source 23 shown in FIG. It is in the point that became.

  FIG. 5 is an exemplary diagram of the in-vehicle DSRC / VICS transmission / reception apparatus according to Embodiment 2 of the present invention. In order to remove the power line, FIG. 5 is obtained by adding the following two modifications to the circuit of FIG.

  The first change is that the power supply line between the power supply 13 and the power supply 23 in FIG. 4 is removed, and at the same time, the power supply signal from the power supply 23 is superimposed on the coaxial line 5 to supply power to the power supply input 13. I have to.

  The second change is that a power signal removal filter is further provided in a portion that receives a signal from the coaxial line 5 so that the power signal superimposed on the coaxial line 5 in FIG.

  Specifically, a filter (power source) 15 d is further provided in series between the coaxial line 5 and the transmission driver 15. Filters (power supplies) 21d and 24d are further provided in series between the coaxial line 5 and the DSRC processing circuit 21, respectively. Further, the power input 13 is provided with a filter (DSRC) 13a, a filter (light reception) 13b, and a filter (light transmission) 13c for removing signals other than the power signal.

  Any filter (power supply) 15d, 21d, and 24d may be used as long as it can remove a DC power supply signal. For example, it can be easily realized by using a capacitor.

  In order to prevent the power signal from affecting the DSRC antenna 11, the receiving amplifier 14, and the DSRC processing circuit 21, a filter (power source) is usually provided between these circuits and the coaxial line 5 as a protective filter. (Not shown).

  The filter (light reception) 13b may be any filter as long as it can remove a light reception signal of 1024 KHz. For example, a low-pass filter of about 400 KHz configured with an LC circuit can be used.

  The filter (optical transmission) 13c may be any filter as long as it can remove optical transmission signals of 64 KHz and 256 KHz. For example, a low pass filter of about 10 KHz configured with an LC circuit can be used.

  In this case, since the filter (optical transmission) 13c can also remove the 5.8 GHz DSRC signal and 1024 KHz optical reception, the filter (DSRC) 13a and the filter (optical reception) 13b can be integrated into the filter (optical transmission) 13c. Further, the circuit configuration can be simplified. However, since the filter (DSRC) 13a is a very high frequency filter, it may be difficult to integrate, and is generally often installed independently.

  The same ceramic resonator can be used for the filter (light reception) 21b, the filter (light transmission) 21c, and the filter (power supply) 21d. This is because the ceramic resonator functions as any of the optical reception signal elimination filter, the optical transmission signal elimination filter, and the power supply signal elimination filter. Therefore, these three filters can be integrated into one, and the circuit configuration can be simplified.

  The power supply 23 outputs a power supply signal but does not input it. Therefore, a removal filter is not provided between the coaxial line 5 and the power supply 23, but the DSRC signal and the optical transmission / reception signal are prevented from affecting the power supply 23. Therefore, normally, the same filter unit provided between the coaxial line 5 and the power input 13 is provided as a protective filter (not shown).

  In this way, the power supply signal is superposed on the coaxial line 5, and the power line is unnecessary by providing a power signal removal filter in the portion that receives the signal from the coaxial line 5 so that the power signal does not interfere, In-vehicle DSRC / VICS transmission / reception apparatus can be reduced in cost.

  As described above, according to the third embodiment, the power signal is further superimposed on the coaxial line. Further, a filter unit is provided in a portion that receives a signal from the coaxial line so that the power signal does not interfere. As a result, it is possible to obtain an in-vehicle DSRC / VICS transmission / reception apparatus that supports both the DSRC service and the service using the VICS optical beacon with a simpler circuit configuration from which the power supply line is removed.

Embodiment 4 FIG.
In the first to third embodiments, a method of superimposing a plurality of transmission / reception signals on the coaxial line 5 and further providing a filter unit in a portion that receives signals from the coaxial line 5 so that the plurality of signals do not interfere with each other. Explained. In the fourth embodiment, a method for further simplifying the circuit configuration by integrating filters will be described.

  FIG. 6 is an exemplary diagram of an in-vehicle DSRC / VICS transmission / reception device according to Embodiment 4 of the present invention. FIG. 6 is an integration of several filters of the circuit of FIG.

  Specifically, the filters (DSRC) 13a and 15a are integrated into a filter (DSRC) 15a, and the filters (optical reception) 13b and 15b are integrated into a filter (optical reception) 15b.

As described above, according to the fourth embodiment, by integrating filters, an in-vehicle DSRC / VICS transmission / reception device that supports both the DSRC service and the VICS optical beacon service can be obtained with a simpler circuit configuration. be able to.
Embodiment 5 FIG.

  In the fifth embodiment, a method for avoiding interference between an optical reception signal and an optical transmission signal without using a filter by controlling the amplitude and timing of the optical reception signal and the optical transmission signal will be described.

  The feature of the fifth embodiment is that, instead of using a filter, the waveform and timing of the optical reception signal and the optical transmission signal are controlled so that the optical reception signal and the optical transmission signal do not interfere with each other. A specific control method will be described below.

  First, the DSRC processing circuit 21 is controlled so that the waveform of the optical transmission signal is a digital signal having an L value of zero and an H value equal to or higher than the input threshold value of the transmission driver 15.

  Next, the amplification factor of the reception amplifier 14 is adjusted so that the amplitude of the optical reception signal is always smaller than the input threshold value of the transmission driver 15.

  Thus, by controlling the amplitudes of the optical transmission signal and the optical reception signal, the optical reception signal can be prevented from affecting the optical transmission signal.

  For example, the L value and H value of the digitized optical transmission signal are set to 0 V and 3.3 V, respectively, and the threshold value of the transmission driver 15 is set to about 1.65 V which is half of the H value. At this time, if the optical amplifier is adjusted so that the amplitude of the optical reception signal does not exceed 1.65 V, the transmission driver 15 is not driven, so that the optical reception signal does not affect the optical transmission signal.

  Further, the DSRC processing circuit 21 controls the output timing of the optical transmission signal so that the optical transmission signal is not output while the optical reception signal is received, so that the optical transmission signal does not affect the optical reception signal. can do.

  Thus, by controlling the amplitude and timing of the optical reception signal and the optical transmission signal, interference between the optical reception signal and the optical transmission signal can be prevented without using a filter. As a result, the filter (light reception) and the filter (light transmission) can be integrated or removed.

  FIG. 7 is an exemplary diagram of the in-vehicle DSRC / VICS transmission / reception device according to the fifth embodiment of the present invention. In FIG. 7, the filter (light reception) and the filter (light transmission) of the circuit of FIG. 6 are integrated or removed.

  Specifically, the filter (light transmission / reception) 13c and the filter (light reception) 15b are integrated into a filter (light transmission / reception) 13e. Also, the filter (optical transmission / reception) 21e is integrated with the filter (optical reception) 21b and the filter (optical transmission) 21c. Further, the filter (optical transmission) 15b and the filter (optical reception) 24c are removed.

  As described above, according to the fifth embodiment, the amplitude and timing of the optical reception signal and the optical transmission signal are controlled. As a result, it is possible to prevent interference between the optical reception signal and the optical transmission signal without using a filter, and with a simple circuit configuration, both in-vehicle DSRC / VICS that supports both the DSRC service and the VICS optical beacon service. A transmission / reception device can be obtained.

  In the fifth embodiment described above, the case where both the amplitude and timing of the optical reception signal and the optical transmission signal are controlled has been described. However, the present invention is not limited to such control. Prevents interference between the optical reception signal and the optical transmission signal without using a filter by controlling only the amplitude of the optical reception signal and the optical transmission signal, or controlling only the timing of the optical reception signal and the optical transmission signal. Is possible.

  1 DSRC antenna unit, 2 DSRC signal processing unit, 3 car navigation system, 4 VICS antenna unit, 5 coaxial line, 6 DSRC serial line, 7 VICS serial line, 8 conventional DSRC transceiver, 9 conventional VICS transceiver, 11 DSRC Antenna, 12 Optical antenna, 13 Power input, 13a filter (DSRC), 13b filter (optical reception), 13c filter (optical transmission), 13e filter (optical transmission / reception), 14 reception amplifier, 15 transmission driver, 15a filter (DSRC) ), 15b filter (optical reception), 15d filter (power supply), 21 DSRC processing circuit, 21b filter (optical reception), 21c filter (optical transmission), 21d filter (power supply), 21e filter (optical transmission / reception), 23 power supply, 24 External I / F, 24a Filter (DSRC), 24c filter (optical transmission), 24d filter (power supply), 31 car navigation processing circuit, 32 determination unit, 33 VICS I / F, 34 DSRC I / F, 41 radio wave antenna, 42 optical antenna, 44 reception amplifier 45 Transmission driver, 91 Radio wave / optical signal processing circuit, 92 External I / F.

Claims (6)

An antenna unit for receiving a DSRC signal from a DSRC (registered trademark) beacon, transmitting a DSRC signal to the DSRC beacon, receiving an optical reception signal from an optical beacon, and transmitting an optical transmission signal to the optical beacon;
The DSRC signal and the optical transmission signal to be transmitted to the outside through the antenna unit are generated and transmitted to the antenna unit, and based on the DSRC signal and the optical reception signal received by the antenna unit, respectively. An in-vehicle DSRC / VICS (registered trademark) transmission / reception device comprising: a signal processing unit that generates road traffic information and outputs the information to the outside;
The optical transmission signal and the optical reception signal are transmitted via a coaxial line provided between the antenna unit and the signal processing unit to transmit the DSRC signal,
When all three signals of the optical reception signal, the optical transmission signal, and the DSRC signal are transmitted through the coaxial line,
The antenna unit receives the optical transmission signal output from the signal processing unit by receiving a signal from the coaxial line via the first filter unit,
The signal processing unit receives the signal from the coaxial line via the second filter unit, thereby receiving the DSRC signal output from the antenna unit, and the third filter unit from the coaxial line. Receiving the optical reception signal output from the antenna unit by receiving a signal via
The first filter unit, the second filter unit, and the third filter unit are realized by combining a λ / 4 short stub and a removal filter using an RL circuit or an RC circuit. In-vehicle DSRC / VICS transceiver. In the vehicle-mounted DSRC / VICS transmission / reception device according to claim 1,
The antenna unit outputs the optical reception signal to the coaxial line as a signal having a first amplitude,
The signal processing unit outputs the optical transmission signal to the coaxial line as a signal having a second amplitude different from the first amplitude,
The antenna unit receives the optical transmission signal from the coaxial line by using a filter that extracts a signal having the second amplitude as the first filter unit,
The signal processing unit receives the optical reception signal from the coaxial line by using a filter that extracts the signal having the first amplitude as the third filter unit. Transmitter / receiver. In the vehicle-mounted DSRC / VICS transmission / reception device according to claim 1 or 2,
The antenna unit outputs the optical reception signal to the coaxial line at a first timing,
The signal processing unit outputs the optical transmission signal to the coaxial line at a second timing different from the first timing,
The antenna unit receives the optical transmission signal from the coaxial line at the second timing,
The in-vehicle DSRC / VICS transmission / reception apparatus, wherein the signal processing unit receives the optical reception signal from the coaxial line at the first timing. In the in-vehicle DSRC / VICS transceiver device according to any one of claims 1 to 3,
The signal processing unit has a power source that outputs a power signal commonly used in the antenna unit and the signal processing unit,
The vehicle-mounted DSRC / VICS transmission / reception device, wherein the power signal is transmitted through the coaxial line. The in-vehicle DSRC / VICS transmission / reception device according to claim 4,
The in-vehicle DSRC / VICS transmission / reception apparatus, wherein the antenna unit receives the power signal output from the signal processing unit by receiving a signal from the coaxial line via a fourth filter unit. An antenna unit for receiving a DSRC signal from a DSRC beacon, transmitting a DSRC signal to the DSRC beacon, receiving an optical reception signal from an optical beacon, and transmitting an optical transmission signal to the optical beacon;
The DSRC signal and the optical transmission signal to be transmitted to the outside through the antenna unit are generated and transmitted to the antenna unit, and the road is based on the DSRC signal and the optical reception signal received by the antenna unit. A transmission / reception data transmission method used for an in-vehicle DSRC / VICS transmission / reception device comprising a signal processing unit that generates traffic information and outputs the traffic information to the outside,
Transmitting the optical transmission signal and the optical reception signal via a coaxial line provided between the antenna unit and the signal processing unit to transmit the DSRC signal;
When all three signals of the optical reception signal, the optical transmission signal, and the DSRC signal are transmitted through the coaxial line,
The antenna unit receives the optical transmission signal output from the signal processing unit by receiving a signal from the coaxial line via the first filter unit;
The signal processing unit receives the signal from the coaxial line via the second filter unit, thereby receiving the DSRC signal output from the antenna unit, and the third filter unit from the coaxial line. Receiving the optical reception signal output from the antenna unit by receiving a signal via
The first filter unit, the second filter unit, and the third filter unit are realized by combining a λ / 4 short stub and a removal filter using an RL circuit or an RC circuit. A transmission / reception data transmission method used for an in-vehicle DSRC / VICS transmission / reception device.

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