JP2020022105A - On-vehicle antenna unit and on-vehicle system - Google Patents

Abstract

To provide an on-vehicle antenna unit capable of improving communication stability.SOLUTION: An on-vehicle antenna unit is connected with an on-vehicle device. The on-vehicle antenna unit includes: a first antenna that radiates radio waves on receiving a first high frequency signal output from the on-vehicle device or outputting a first high frequency signal to the on-vehicle device on receiving radio waves; a radio communication device for outputting a second high frequency signal on receiving a serial signal; and a second antenna for radiating radio waves on receiving the second high frequency signal output from the radio communication device.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle-mounted antenna unit and a vehicle-mounted system.

  Patent Literature 1 discloses a vehicle-mounted integrated antenna device in which an antenna element for satellite communication and an antenna element for road-vehicle communication are mounted on the same circuit board.

Japanese Patent No. 3960255

  By the way, in a wireless communication device having a relatively low output, if the transmission path between the wireless communication device and the antenna becomes long, transmission loss may increase and communication may become unstable.

  The present invention has been made in view of the above problems, and a main object of the present invention is to provide a vehicle-mounted antenna unit and a vehicle-mounted system capable of improving communication stability.

  In order to solve the above problem, an on-vehicle antenna unit according to one embodiment of the present invention is an on-vehicle antenna unit connected to an on-vehicle device, and receives a first high-frequency signal output from the on-vehicle device and emits a radio wave. Or a first antenna for receiving a radio wave and outputting a first high-frequency signal to the on-vehicle device, a wireless communication device for receiving a serial signal and outputting a second high-frequency signal, and a second high-frequency signal output from the wireless communication device A second antenna that receives a signal and emits a radio wave.

  Further, an on-vehicle system according to another aspect of the present invention includes an on-vehicle device and an on-vehicle antenna unit connected to the on-vehicle device, wherein the on-vehicle antenna unit transmits a first high-frequency signal output from the on-vehicle device. A first antenna that receives and emits a radio wave, or receives a radio wave and outputs a first high-frequency signal to the vehicle-mounted device, a wireless communication device that receives a serial signal and outputs a second high-frequency signal, A second antenna that receives the output second high-frequency signal and radiates radio waves.

  In addition, an on-vehicle antenna unit according to another aspect of the present invention is an on-vehicle antenna unit connected to an on-vehicle device, which receives a first high-frequency signal output from the on-vehicle device to emit a radio wave, or receives a radio wave. A first antenna for outputting a first high-frequency signal to the on-vehicle device, a second antenna for receiving a radio wave and outputting a second high-frequency signal, and a serial signal for receiving the second high-frequency signal output from the second antenna. And a wireless communication device that outputs

  Further, an on-vehicle system according to another aspect of the present invention includes an on-vehicle device and an on-vehicle antenna unit connected to the on-vehicle device, wherein the on-vehicle antenna unit transmits a first high-frequency signal output from the on-vehicle device. A first antenna for receiving and radiating a radio wave, or receiving a radio wave and outputting a first high-frequency signal to the vehicle-mounted device, a second antenna for receiving a radio wave and outputting a second high-frequency signal, and an output from the second antenna A wireless communication device that receives the generated second high-frequency signal and outputs a serial signal.

  According to the present invention, it is possible to improve communication stability.

It is a block diagram showing the example of composition of the in-vehicle system concerning a 1st embodiment. It is a block diagram showing the example of composition of the in-vehicle system concerning a 2nd embodiment. It is a block diagram showing the example of composition of the in-vehicle system concerning a 3rd embodiment. It is a block diagram showing the example of composition of the in-vehicle system concerning a 4th embodiment. FIG. 2 is a block diagram illustrating a configuration example of a wireless communication device. FIG. 3 is a block diagram illustrating a configuration example of a wireless remote controller. It is a block diagram showing the example of composition of the in-vehicle system concerning a modification. It is a block diagram showing the example of composition of the in-vehicle system concerning a modification.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Each of the embodiments described below exemplifies a method and an apparatus for embodying the technical idea of the present invention, and the technical idea of the present invention is not limited to the following. Absent. Various changes can be made to the technical idea of the present invention within the technical scope described in the claims.

  FIG. 1 to FIG. 4 are block diagrams illustrating configuration examples of in-vehicle systems 1A to 1D according to the first to fourth embodiments. In the following description, the on-vehicle systems 1A to 1D according to the first to fourth embodiments are collectively referred to as “on-vehicle system 1”, and the on-vehicle devices 2A to 2D according to the first to fourth embodiments are collectively referred to as “on-vehicle devices”. 2 ", and the on-vehicle antenna units 3A to 3D according to the first to fourth embodiments may be collectively referred to as" on-vehicle antenna unit 3 ".

[First Embodiment]
As shown in FIG. 1, the vehicle-mounted system 1 includes a vehicle-mounted device 2 and a vehicle-mounted antenna unit 3. The vehicle-mounted device 2 is an ETC vehicle-mounted device used in an electronic toll collection system (ETC), and wirelessly communicates with a roadside device provided at an entrance or the like of a toll road via a vehicle-mounted antenna unit 3. However, the present invention is not limited thereto, and the vehicle-mounted device 2 may be a car navigation device or the like.

  The vehicle-mounted antenna unit 3 is a unit in which a plurality of antennas 35, 37, and 39 are housed in a housing. The vehicle-mounted device 2 is disposed, for example, inside the dashboard of the vehicle, and the vehicle-mounted antenna unit 3 is disposed at a position where radio waves from the outside of the vehicle are easily received, for example, at an upper portion of a front windshield of the vehicle.

  The vehicle-mounted device 2 and the vehicle-mounted antenna unit 3 are connected to each other via a coaxial cable 9. The coaxial cable 9 is used not only for transmitting a high-frequency signal (RF signal) but also for supplying DC power. In this specification, a high frequency refers to a frequency that can be used for a carrier wave of wireless communication (for example, 10 kHz or more).

  The vehicle-mounted device 2 includes a power supply circuit 21, a wireless control unit 23, a GNSS receiving unit 25, and an ETC communication unit 27. The power supply circuit 21 supplies DC power supplied from a battery of the vehicle to each unit of the vehicle-mounted device 2 and the vehicle-mounted antenna unit 3.

  The GNSS receiver 25 calculates the current position based on the radio waves received by the GNSS antenna 35 included in the vehicle-mounted antenna unit 3. When receiving a radio wave from a Global Navigation Satellite System (GNSS), the GNSS antenna 35 converts the received radio wave into a high-frequency signal, and converts the converted high-frequency signal via an LNA (low-noise amplifier) 36 on a vehicle. Output to the container 2.

  The GNSS antenna 35 is an example of a “first antenna”, and the high-frequency signal for GNSS output from the GNSS antenna 35 is an example of a “first high-frequency signal”.

  The ETC communication unit 27 transmits and receives information such as an ETC number or a toll read from the ETC card 29 via an ETC antenna 37 included in the vehicle-mounted antenna unit 3. When receiving the high-frequency signal from the vehicle-mounted device 2, the ETC antenna 37 converts the received high-frequency signal into a radio wave and radiates the converted radio wave. When receiving an electric wave from the roadside device, the ETC antenna 37 converts the received electric wave into a high-frequency signal, and outputs the converted high-frequency signal to the vehicle-mounted device 2.

  The ETC antenna 37 is also an example of the “first antenna”, and the ETC high-frequency signal received or output by the ETC antenna 37 is also an example of the “first high-frequency signal”.

  The wireless control unit 23 generates and outputs a serial signal to be supplied to the wireless communication device 33 included in the vehicle-mounted antenna unit 3. When receiving the serial signal, the wireless communication device 33 generates a high-frequency signal based on the received serial signal and outputs the signal to the antenna 39. When receiving the high-frequency signal from the wireless communication device 33, the antenna 39 converts the received high-frequency signal into a radio wave and radiates the converted radio wave.

  The antenna 39 connected to the wireless communication device 33 is an example of a “second antenna”, and the high-frequency signal output by the wireless communication device 33 and received by the antenna 39 is an example of a “second high-frequency signal”.

  The wireless communication device 33 is, for example, an LPWA (Low Power Wide Area) communication module that implements an LPWA communication method. Not limited to this, the wireless communication device 33 may be, for example, a 3G communication module or the like. The wireless control unit 23 supplies the wireless communication device 33 with a serial signal indicating, for example, meter information such as the total mileage of the vehicle, remaining fuel information, self-diagnosis information (OBD information), or current position information. The information is used for services such as remote vehicle diagnosis, insurance premium calculation, or stolen vehicle tracking.

  FIG. 5 is a block diagram illustrating a configuration example of the wireless communication device 33. The wireless communication device 33 includes an RFIC (high-frequency integrated circuit) 61, a transmission filter 63, a reception filter 65, a transmission / reception switching unit (for example, a transmission / reception switching switch) 67, and an oscillator 69. RFIC 61 includes a modulator 612 and a demodulator 614.

  The modulator 612 of the RFIC 61 modulates the high-frequency signal generated by the oscillator 69 in accordance with the serial signal, and outputs the modulated high-frequency signal to the antenna 39 via the transmission filter 63. When a high-frequency signal is input from the antenna 39 via the reception filter 65, the demodulator 614 of the RFIC 61 demodulates a serial signal from the high-frequency signal.

  Returning to the description of FIG. 1, the vehicle-mounted device 2A and the vehicle-mounted antenna unit 3A according to the first embodiment include the serial signal, the GNSS high-frequency signal, the ETC high-frequency signal, and the DC power in the signal transmitted through the coaxial cable 9. And a extracting unit 5A for extracting a serial signal, a high-frequency signal for GNSS, a high-frequency signal for ETC, and DC power from a signal transmitted through the coaxial cable 9.

  Specifically, the synthesis unit 4A includes a coupling circuit 41 and a modulation circuit 43. The modulation circuit 43 modulates the serial signal from the wireless control unit 23 and outputs the modulated serial signal to the coupling circuit 41. The modulation circuit 43 modulates the serial signal at a frequency different from the high-frequency signal for ETC and the high-frequency signal for GNSS. The coupling circuit 41 superimposes the modulated serial signal from the modulation circuit 43, the high-frequency signal for ETC from the ETC communication unit 27, and the DC power from the power supply circuit 21, and transmits the superposed signal to the coaxial cable 9.

  The extraction unit 5A includes a demultiplexing circuit 51 and a demodulation circuit 53. The demultiplexing circuit 51 separates a modulated serial signal, a high-frequency signal for ETC, and DC power from a signal transmitted through the coaxial cable 9 according to a frequency. The demultiplexing circuit 51 outputs the separated high-frequency signal for ETC to the ETC antenna 37, and outputs the separated DC power to the power supply line 38. The DC power output to the power supply line 38 is supplied to the wireless communication device 33 and the LNA 36.

  The demultiplexing circuit 51 outputs the modulated serial signal to the demodulation circuit 53. The demodulation circuit 53 demodulates the serial signal from the modulated serial signal and outputs the demodulated serial signal to the wireless communication device 33. When receiving the serial signal from the demodulation circuit 53, the wireless communication device 33 generates a high-frequency signal based on the received serial signal and outputs the signal to the antenna 39.

  According to the first embodiment described above, by including the wireless communication device 33 in the vehicle-mounted antenna unit 3A, the distance between the wireless communication device 33 and the antenna 39 is greater than when the wireless communication device 33 is included in the vehicle-mounted device 2A. Can be shortened, so that the communication stability can be improved even if the wireless communication by the wireless communication device 33 is a relatively low-output communication method such as LPWA.

  In the above description, the mode in which the in-vehicle system 1A includes the configuration related to the GNSS reception (the GNSS receiving unit 25, the GNSS antenna 35, and the LNA 36) is described. However, the present invention is not limited to this, and the in-vehicle system 1Ab shown in FIG. The configuration related to reception may be omitted. That is, the GNSS receiving unit 25 may be omitted in the vehicle-mounted device 2Ab, and the GNSS antenna 35 and the LNA 36 may be omitted in the vehicle-mounted antenna unit 3Ab.

  Also, in the above description, the case of transmission by the wireless communication device 33 has been described. However, the case of reception by the wireless communication device 33 is the reverse of the case of transmission, that is, the serial communication from the wireless communication device 33 on the vehicle-mounted antenna unit 3A side. The signal may be included in the signal transmitted through the coaxial cable 9, the serial signal may be extracted from the signal transmitted through the coaxial cable 9 on the vehicle-mounted device 2 </ b> A, and supplied to the wireless control unit 23.

  The case of reception by the wireless communication device 33 will be specifically described. In the on-vehicle system 1Ac shown in FIG. 8, the on-vehicle antenna unit 3Ac has a combining unit 4A, and the on-vehicle unit 2Ac has an extracting unit 5A. The antenna 39 of the in-vehicle antenna unit 3Ac outputs a high-frequency signal to the wireless communication device 33 when receiving a radio wave, and the wireless communication device 33 outputs a serial signal to the combining unit 4A when receiving the high-frequency signal.

  The modulation circuit 43 of the combining unit 4A of the on-vehicle antenna unit 3Ac modulates the serial signal from the wireless communication device 33 and outputs the modulated serial signal to the coupling circuit 41. The coupling circuit 41 superimposes the modulated serial signal from the modulation circuit 43 and the GNSS high-frequency signal from the GNSS antenna 35 and transmits the signal to the coaxial cable 9.

  The demultiplexing circuit 51 of the extraction unit 5A of the vehicle-mounted device 2Ac separates the modulated serial signal and the GNSS high-frequency signal from the signal transmitted through the coaxial cable 9 according to the frequency. The demultiplexing circuit 51 outputs the separated high-frequency signal for GNSS to the GNSS receiving unit 25 and outputs the modulated serial signal to the demodulation circuit 53. The demodulation circuit 53 demodulates a serial signal from the modulated serial signal and outputs the demodulated serial signal to the wireless control unit 23.

[Second embodiment]
FIG. 2 is a block diagram illustrating a configuration example of an in-vehicle system 1B according to the second embodiment. The same components as those in the above embodiment are denoted by the same reference numerals, and detailed description is omitted.

  The combining unit 4B of the vehicle-mounted device 2B according to the second embodiment includes a power control unit 45. The power supply control unit 45 can switch the DC power voltage between a high level (for example, 5 V) and a low level (for example, 3.3 V). The power control unit 45 switches the level of the voltage according to the serial signal from the wireless control unit 23 to generate power having a voltage level pattern corresponding to the serial signal, and outputs the generated power to the coupling circuit 41.

  The coupling circuit 41 includes the power having the voltage high / low pattern from the power control unit 45 in the signal transmitted through the coaxial cable 9. The frequency of the voltage high / low pattern is sufficiently lower than the high frequency signal for ETC and the high frequency signal for GNSS.

  The extraction unit 5B of the vehicle-mounted antenna unit 3B according to the second embodiment includes a comparator 55. The comparator 55 extracts the serial signal by comparing the power separated by the branching circuit 51 with a reference voltage (for example, 4 V) to detect a voltage high / low pattern, and outputs the serial signal to the wireless communication device 33.

  It is preferable that the low level of the power having the voltage high / low pattern is set to a level at which the wireless communication device 33 and the LNA 36 included in the vehicle-mounted antenna unit 3B can operate. This allows the wireless communication device 33 and the LNA 36 to continue operating even when power having a voltage high / low pattern is supplied to the power supply line 38.

  Also in the above-described second embodiment, the communication stability can be improved by including the wireless communication device 33 in the vehicle-mounted antenna unit 3B, as in the first embodiment.

  In the above description, the case of transmission by the wireless communication device 33 has been described. However, the case of reception by the wireless communication device 33 will be described in a fourth embodiment described later.

[Third embodiment]
FIG. 3 is a block diagram illustrating a configuration example of an in-vehicle system 1C according to the third embodiment. The same components as those in the above embodiment are denoted by the same reference numerals, and detailed description is omitted.

  The vehicle-mounted antenna unit 3C according to the third embodiment includes a wireless remote controller 34. Upon receiving the remote control signal, the wireless remote controller 34 generates a high-frequency signal including information for remote control, and outputs the signal to the antenna 39. The wireless remote controller 34 is an example of a “wireless communication device”. The wireless remote controller 34 is, for example, a remote controller for transmitting a high-frequency signal for controlling opening and closing of an electric shutter of a garage.

  The wireless control unit 23 of the vehicle-mounted device 2C according to the third embodiment generates and outputs a remote control signal. The remote control signal is an example of a “serial signal”, for example, a pulse signal whose high level indicates a transmission command and whose low level indicates off. The wireless control unit 23 outputs a remote control signal when, for example, an operation is performed by a user or when the vehicle approaches the garage.

  The power control unit 45 switches the level of the voltage according to the remote control signal from the wireless control unit 23 to generate power having a voltage level pattern according to the remote control signal, and outputs the generated power to the coupling circuit 41. The coupling circuit 41 includes the power having the voltage high / low pattern from the power control unit 45 in the signal transmitted through the coaxial cable 9.

  The comparator 55 included in the in-vehicle antenna unit 3C extracts the remote control signal by detecting the voltage high / low pattern by comparing the power separated by the demultiplexing circuit 51 with the reference voltage, and outputs it to the wireless remote control 34. Upon receiving the remote control signal, the wireless remote controller 34 generates a high-frequency signal including information for remote control, and outputs the signal to the antenna 39.

  FIG. 6 is a block diagram illustrating a configuration example of the wireless remote controller 34. The wireless remote controller 34 includes a control unit 71, a memory 73, and a wireless transmission unit 75. The memory 73 stores, for example, predetermined codes such as ID information and an opening / closing command.

  When detecting the transmission command included in the remote control signal, the control unit 71 reads the code from the memory 73 and outputs the code to the wireless transmission unit 75. Radio transmitting section 75 generates a high-frequency signal representing the code and outputs the signal to antenna 39.

  Also in the third embodiment described above, the communication stability can be improved by including the wireless remote controller 34 in the vehicle-mounted antenna unit 3C, as in the first and second embodiments.

  Note that, similarly to the second embodiment, the wireless control unit 23 included in the vehicle-mounted device 2C generates a serial signal representing a code, and transmits the serial signal to the wireless remote controller 34 (corresponding to the wireless transmission unit 75) included in the vehicle-mounted antenna unit 3C. You may comprise so that it may output.

[Fourth embodiment]
FIG. 4 is a block diagram illustrating a configuration example of an in-vehicle system 1D according to the fourth embodiment. The same components as those in the above embodiment are denoted by the same reference numerals, and detailed description is omitted.

  In the fourth embodiment, the vehicle-mounted device 2D includes a current-voltage conversion unit 47, and the vehicle-mounted antenna unit 3D includes a load control unit 57. The current-voltage converter 47 and the load controller 57 are provided on a current path 90 from the vehicle-mounted device 2D to the vehicle-mounted antenna unit 3D.

  The current path 90 includes a current path 91 from the power supply circuit 21 of the vehicle-mounted device 2D to the coupling circuit 41, a coaxial cable 9, and a current path 92 from the branching circuit 51 of the vehicle-mounted antenna unit 3D to the wireless communication device 33. . The current-voltage converter 47 is provided on the current path 91 of the vehicle-mounted device 2D, and the load controller 57 is provided on the current path 92 of the vehicle-mounted antenna unit 3D.

  When receiving the radio wave, the antenna 39 of the vehicle-mounted antenna unit 3D converts the received radio wave into a high-frequency signal, and outputs the converted high-frequency signal to the wireless communication device 33. When receiving the high-frequency signal from the antenna 39, the wireless communication device 33 demodulates a serial signal from the received high-frequency signal and outputs the signal to the load control unit 57.

  The load control unit 57 controls the load on the current path 92 according to the serial signal from the wireless communication device 33. As a result, the current flowing through the current path 90 is given a current height pattern corresponding to the serial signal. The load controller 57 is an electronic load device including, for example, an FET.

  The current-voltage converter 47 of the on-vehicle device 2D generates a serial signal according to the current height pattern by converting the current height pattern of the current flowing through the current path 90 into a voltage, and outputs the serial signal to the wireless controller 23. Thus, the wireless control unit 23 can receive the serial signal output by the wireless communication device 33.

  The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments.

  In the first to fourth embodiments described above, the in-vehicle antenna units 3A to 3D include the GNSS antenna 35 and the ETC antenna 37. However, the present invention is not limited thereto. May be configured as a GNSS antenna unit connected to the GNSS.

  In the first to fourth embodiments described above, transmission of a serial signal is realized by using the coaxial cable 9 that connects the vehicle-mounted devices 2A to 2D and the vehicle-mounted antenna units 3A to 3D to each other. However, the present invention is not limited to this, and a dedicated transmission line for transmitting a serial signal may be separately provided.

1 (1A to 1D) on-board system, 2 (2A to 2D) on-board unit, 21 power supply circuit, 23 wireless control unit, 25 GNSS receiving unit, 27 ETC communication unit, 29 ETC card, 3 (3A to 3D) on-board antenna unit , 33 wireless communication device, 34 wireless remote controller (example of wireless communication device), 35 GNSS antenna (example of first antenna), 36 LNA, 37 ETC antenna (example of first antenna), 38 power supply line, 39 antenna ( Example of second antenna), 4 (4A to 4C) combining section, 41 coupling circuit, 43 modulation circuit, 45 power control section, 47 current-voltage conversion section, 5 (5A to 5C) extraction section, 51 demultiplexing circuit, 53 Demodulation circuit, 55 comparator, 57 load controller, 61 RFIC, 612 modulator, 614 demodulator, 63 filter, 65 filter, 67 switch, 6 9 oscillator, 71 control unit, 73 memory, 75 wireless transmission unit, 9 coaxial cable, 90-92 current path

Claims (17)

An on-vehicle antenna unit connected to the on-vehicle device,
A first antenna that receives the first high-frequency signal output from the vehicle-mounted device and emits a radio wave, or receives a radio wave and outputs the first high-frequency signal to the vehicle-mounted device;
A wireless communication device that receives a serial signal and outputs a second high-frequency signal;
A second antenna that receives a second high-frequency signal output from the wireless communication device and emits a radio wave;
A vehicle-mounted antenna unit comprising: The vehicle-mounted antenna unit is connected to the vehicle-mounted device via a coaxial cable,
An extraction unit that extracts the first high-frequency signal and the serial signal from a signal transmitted through the coaxial cable,
The vehicle-mounted antenna unit according to claim 1. The signal transmitted through the coaxial cable includes DC power,
The extraction unit extracts the DC power from a signal transmitted through the coaxial cable, and supplies the DC power to the wireless communication device.
The vehicle-mounted antenna unit according to claim 2. The signal transmitted through the coaxial cable includes the modulated serial signal,
The extraction unit extracts the serial signal by demodulating the modulated serial signal,
The vehicle-mounted antenna unit according to claim 2. The signal transmitted through the coaxial cable includes power having a voltage high / low pattern according to the serial signal,
The extraction unit extracts the serial signal by detecting a voltage level pattern of the power,
The vehicle-mounted antenna unit according to claim 2. The wireless communication device,
An oscillator for generating a high-frequency signal;
A modulator that generates the second high-frequency signal by modulating a high-frequency signal generated by the oscillator according to the serial signal;
including,
An in-vehicle antenna unit according to claim 1. The wireless communication device,
A memory for storing a predetermined code;
When a transmission command included in the serial signal is detected, a wireless transmission unit that transmits the second high-frequency signal representing a code stored in the memory,
including,
The vehicle-mounted antenna unit according to claim 1. The first antenna is an ETC antenna;
The vehicle-mounted antenna unit according to claim 1. The first antenna is a GNSS antenna;
The vehicle-mounted antenna unit according to claim 1. An on-vehicle antenna unit connected to the on-vehicle device,
A first antenna that receives the first high-frequency signal output from the vehicle-mounted device and emits a radio wave, or receives a radio wave and outputs the first high-frequency signal to the vehicle-mounted device;
A second antenna for receiving a radio wave and outputting a second high-frequency signal;
A wireless communication device that receives the second high-frequency signal output from the second antenna and outputs a serial signal;
A vehicle-mounted antenna unit comprising: A load control unit that controls a load on a current path from the vehicle-mounted device to the vehicle-mounted antenna unit in accordance with a serial signal output from the wireless communication device,
The vehicle-mounted antenna unit according to claim 10. Onboard equipment,
A vehicle-mounted antenna unit connected to the vehicle-mounted device,
With
The in-vehicle antenna unit,
A first antenna that receives the first high-frequency signal output from the vehicle-mounted device and emits a radio wave, or receives a radio wave and outputs the first high-frequency signal to the vehicle-mounted device;
A wireless communication device that receives a serial signal and outputs a second high-frequency signal;
A second antenna that receives a second high-frequency signal output from the wireless communication device and emits a radio wave;
An in-vehicle system comprising: The on-vehicle device is connected to the on-vehicle antenna unit via a coaxial cable,
A synthesizing unit that includes the first high-frequency signal and the serial signal in a signal transmitted through the coaxial cable,
An in-vehicle system according to claim 12. The combining unit includes the modulated serial signal in a signal transmitted through the coaxial cable,
An in-vehicle system according to claim 13. The combining unit includes a power having a voltage high / low pattern according to the serial signal in a signal transmitted through the coaxial cable.
An in-vehicle system according to claim 13. Onboard equipment,
A vehicle-mounted antenna unit connected to the vehicle-mounted device,
With
The in-vehicle antenna unit,
A first antenna that receives the first high-frequency signal output from the vehicle-mounted device and emits a radio wave, or receives a radio wave and outputs the first high-frequency signal to the vehicle-mounted device;
A second antenna for receiving a radio wave and outputting a second high-frequency signal;
A wireless communication device that receives the second high-frequency signal output from the second antenna and outputs a serial signal;
An in-vehicle system comprising: The vehicle-mounted device further includes a conversion unit that generates a serial signal according to a current level pattern of a current path from the vehicle-mounted device to the vehicle-mounted antenna unit,
An in-vehicle system according to claim 16.

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