JP6160246B2 - Wireless communication device for vehicle - Google Patents

Description

  The present invention relates to a vehicular radio communication apparatus in which an antenna module including an antenna and a radio communication unit is installed on an outer surface of a vehicle body.

  2. Description of the Related Art Conventionally, there is known a wireless communication device that detects the temperature of a wireless communication unit that performs wireless communication via an antenna and determines that it is abnormal if the temperature is equal to or higher than a certain threshold temperature (for example, Patent Document 1). In Patent Document 1, if it is determined that there is an abnormality, the transmission process is temporarily stopped.

JP 2011-217171 A

  In a wireless communication device for a vehicle, an antenna and a wireless communication unit that performs wireless communication via the antenna may be installed as one module (hereinafter referred to as an antenna module) on the outer surface of the vehicle body such as a vehicle roof surface. It is being considered. This is because the loss occurring between the antenna and the wireless communication unit is reduced by arranging the wireless communication unit near the antenna.

  However, when the antenna module is installed on a vehicle roof surface or the like, the wireless communication unit is placed in an environment where the temperature change is large. Therefore, when it is judged abnormal by simple comparison with a threshold temperature that is a constant value as in the past, it is actually normal, but it is erroneously judged to be abnormal, and conversely, it is actually abnormal. However, there is a risk that it is mistakenly determined to be normal.

  The present invention has been made based on this situation, and an object of the present invention is to provide a vehicle wireless communication apparatus in which the wireless communication unit is modularized with an antenna and installed on the outer surface of the vehicle body. It is to determine abnormality with high accuracy.

A first invention for achieving the object is an antenna (110A, 110B) installed on the outer surface of a vehicle body, a wireless communication unit (190) for performing wireless communication via the antenna, and the wireless communication unit. An antenna module (100, 100A) having a temperature sensor (192) for detecting temperature, and whether or not the temperature of the wireless communication unit is installed in the vehicle and abnormal, and the wireless communication A communication ECU (200, 200A) for controlling the unit, and an in-device communication unit (20) for communication between the antenna module and the communication ECU, wherein the communication ECU is an environmental temperature of the wireless communication unit amount of sunlight is a change in ambient temperature parameters that affect the vehicle speed, the abnormality determination threshold based on at least one acquired, the environmental temperature change parameter obtained by the outside air temperature And determining whether or not the temperature of the wireless communication unit is abnormal based on a comparison between the set abnormality determination threshold and the temperature of the wireless communication unit detected by the temperature sensor. Wireless communication device (1, 1A).
The second invention for achieving the object is the antenna (110A, 110B) installed on the outer surface of the vehicle body, the wireless communication unit (190) for performing wireless communication via the antenna, and the wireless communication. An antenna module (100, 100A) provided with a temperature sensor (192) for detecting the temperature of the unit, and installed in the vehicle to determine whether the temperature of the wireless communication unit is abnormal, and A communication ECU (200, 200A) that controls a wireless communication unit; and an in-device communication unit (20) that communicates between the antenna module and the communication ECU, wherein the communication ECU is in a normal state. A temperature change parameter that affects the temperature change of the wireless communication unit is acquired, an abnormality determination threshold is set based on the acquired temperature change parameter, and the set abnormality determination threshold Based on the comparison with the temperature of the wireless communication unit detected by the temperature sensor, it is determined whether or not the temperature of the wireless communication unit is abnormal. It is also determined which of the levels, wireless transmission is stopped when the abnormal level is the highest, and preset when corresponding to the abnormal level when the abnormal level is lower than the highest level. The vehicle wireless communication device (1, 1A) is characterized by performing control to reduce transmission power.

  According to the present invention, the communication ECU acquires a temperature change parameter that changes the temperature of the wireless communication unit that is in a normal state, and sets an abnormality determination threshold value based on the temperature change parameter. Therefore, the abnormality determination threshold changes according to the temperature change when the wireless communication unit is normal. It is determined whether or not the temperature of the wireless communication unit is abnormal based on the comparison between the abnormality determination threshold set in this way and the temperature detected by the temperature sensor. Therefore, it is possible to accurately determine whether or not the temperature of the wireless communication unit that is modularized with the antenna and installed on the outer surface of the vehicle body is abnormal.

The figure which shows the block diagram of the radio | wireless communication apparatus 1 for vehicles of embodiment. The figure explaining the signal input / output with respect to the signal of communication ECU200 Partial sectional view in a state where the antenna module 100 is mounted on the vehicle roof 2 Processing executed by CPU 161 of antenna module 100 Abnormality determination processing executed by CPU 211 of communication ECU 200 Processing to set threshold TH Example of table referred to in step S35 of FIG. Processing to be performed according to the abnormality judgment result An example in which the antenna module 100A and the communication ECU 200A are connected by Bluetooth communication circuits 165 and 251.

(overall structure)
Hereinafter, embodiments of the present invention will be described with reference to the drawings. The vehicle wireless communication device 1 of FIG. 1 includes an antenna module 100 and a communication ECU 200, and is a wireless communication device that performs vehicle-to-vehicle communication and / or road-to-vehicle communication. For example, a 700 MHz band or a 5.9 GHz band is used as a communication frequency for inter-vehicle communication and road-vehicle communication.

  In the present embodiment, the antenna module 100 is installed on the outer surface of the vehicle roof 2 as shown in FIG. On the other hand, the communication ECU 200 is installed at a predetermined position inside the vehicle. The position where the communication ECU 200 is installed is not particularly limited as long as it is inside the vehicle. However, since the electronic ECU is provided, an environment in which temperature change due to sunlight or the like is small is preferable.

(Configuration of antenna module 100)
As shown in FIG. 1, the antenna module 100 includes two antennas 110A and 110B, a changeover switch 120, two low noise amplifiers 130A and 130B, a power amplifier 140, and a communication chip 150. , An interface adapter 160, a switching circuit 170, and a power supply unit 180. Among the above configurations, the configuration excluding the antenna 110 is the wireless communication unit 190. Note that the wireless communication unit 190 only needs to have a function of performing wireless communication via the antenna 110, and is not necessarily limited to the configuration of FIG.

  In addition to the above configuration, the antenna module 100 also includes a temperature sensor 192, a GNSS (Global Navigation Satellite Systems) antenna 194, and a low noise amplifier 196. The GNSS antenna 194 is connected to a low noise amplifier 196, and the low noise amplifier 196 is connected to the coaxial cable 30.

  One of the antennas 110A for vehicle-to-vehicle communication and road-to-vehicle communication 110A is dedicated to reception, and is connected to a low-noise amplifier 130A. On the other hand, the other antenna 110B is used for both reception and transmission. With the changeover switch 120, the antenna 110B is connected to the low noise amplifier 130B at the time of reception, and the antenna 110B is connected to the power amplifier 140 at the time of transmission.

  The communication chip 150 includes two receiving units 151 and 152, a transmitting unit 153, and a baseband processing unit 154. In this embodiment, it is the specification which performs vehicle-to-vehicle communication and road-to-vehicle communication according to the communication standard of IEEE802.11p.

  One receiving unit 151 is connected to the low noise amplifier 130A, and the other receiving unit 152 is connected to the low noise amplifier 130B. During reception, the changeover switch 120 connects the low noise amplifier 130B connected to the receiving unit 152 and the antenna 110B. Therefore, two antennas 110A and 110B are used during reception. The changeover switch 120 is switched by the antenna switching circuit 170. These receiving units 151 and 152 demodulate the input high-frequency signal into a baseband signal, perform filtering and amplification, and send the result to the baseband processing unit 154.

  The transmission unit 153 is connected to the power amplifier 140. At the time of transmission, the changeover switch 120 is switched to connect the power amplifier 140, the transmission unit 153, and the antenna 110B. The transmission unit 153 modulates the signal transmitted from the baseband processing unit 154 into a high frequency band signal and transmits the modulated signal to the power amplifier 140.

  The baseband processing unit 154 performs modulation and demodulation of the baseband signal. At the time of reception, reception diversity (here, maximum ratio combining diversity) is performed.

  The communication chip 150 configured as described above can communicate with the interface adapter 160. The interface adapter 160 includes a CPU 161, a memory 162, and an interface unit (hereinafter referred to as I / F unit) 163. The I / F unit 163 is connected to the Ethernet cable 20 for performing communication according to the Ethernet (registered trademark) communication standard. The Ethernet cable 20 is an in-device communication unit in this embodiment. CPU 161 communicates with communication ECU 200 via Ethernet cable 20 and I / F unit 163. The CPU 161 controls the communication chip 150.

  The switching circuit 170 switches the changeover switch 120 based on the communication state of the communication chip 150.

  The power supply unit 180 is connected to the interface unit 163, and supplies the power supplied via the Ethernet cable 20 to various components constituting the antenna module 100. The temperature sensor 192 is disposed in the vicinity of the wireless communication unit 190 inside the housing 3 (see FIG. 3) of the antenna module 100 in order to detect the temperature of the wireless communication unit 190. The temperature sensor 192 outputs a signal indicating the detected temperature to the interface unit 163.

(Configuration of communication ECU 200)
The communication ECU 200 can communicate with the antenna module 100 via the Ethernet cable 20.

  The communication ECU 200 includes a calculation unit 210, a GNSS reception unit 220, a security access module (SAM) 230, a power supply 240, and an interface unit 250.

  The calculation unit 210 includes a CPU 211, a memory 212, and an I / F unit 213. The I / F unit 213 is connected to a CAN that is a communication network in the vehicle. The CPU 211 can acquire various information in the vehicle from the CAN via the I / F unit 213, or can provide information to devices in the vehicle. Further, the CPU 211 determines whether or not the temperature of the wireless communication unit 190 is abnormal, and controls the wireless communication unit 190 based on the determination result. These processes performed by the CPU 211 will be described later with reference to FIGS.

  The GNSS receiving unit 220 is connected to the GNSS antenna 194 via the coaxial cable 30, and filters, amplifies, and demodulates a signal supplied from the GNSS antenna 194 and supplies received data to the arithmetic unit 210. The SAM 230 encrypts and decrypts signals to be transmitted and received by vehicle-to-vehicle communication or road-to-vehicle communication.

  The power source 240 supplies power to various components inside the communication ECU 200. The power source 240 is connected to the interface unit 250. The Ethernet cable 20 is connected to the I / F unit 250, and the power supply 240 supplies power to the components of the antenna module 100 via the interface unit 250 and the Ethernet cable 20.

(Signal input / output to / from arithmetic unit 210)
As shown in FIG. 2, the communication ECU 200 includes a battery power source (+ B), an accessory signal (ACC), an ignition signal (IG), a ground signal (GND), a signal (Turn signals) indicating a blinking state of the direction indicator lamp, A signal indicating the deployment state of the airbag (Airbag signals) is directly input.

  Further, the communication ECU 200 outputs an HMI request signal and acquires various vehicle information (Vehicle Info) via the CAN bus 40. The HMI request signal is supplied to the HMI device 41. The HMI device 41 is a meter display or the like.

  As shown in FIG. 2, an external air temperature sensor 42, a sunshine sensor 43, a vehicle speed sensor 44, other sensor groups 45, other ECU groups 46 (other than the communication ECU 200), and a navigation device 47 are also connected to the CAN bus 40. ing.

  The communication ECU 200 acquires vehicle information such as outside air temperature, amount of sunlight, vehicle speed, acceleration, yaw rate, and brake signal from the sensors 42 to 45 and the ECU group 46. Further, the communication ECU 200 may be provided with a USB connector 260, and the communication ECU 200 may be configured to be communicable with the navigation device 47 by USB connection via the USB connector 260.

(Vehicle mounting position of antenna module 100)
As shown in FIG. 3, the housing 3 included in the antenna module 100 is formed in a streamlined shape (so-called shark fin shape) from the front of the vehicle to the rear of the vehicle for reasons of external design and the like.

  The ground plane 4 has a substantially rectangular planar shape and is made of a metal plate. In a state in which the antenna module 100 is mounted on the upper surface 2 a of the vehicle roof 2, the ground plane 4 is along the upper surface 2 a of the vehicle roof 2. On the ground plane surface 4a which is the upper surface portion of the ground plane 4, a flat printed wiring board 5 made of resin is erected substantially perpendicular to the ground plane surface 4a.

  On one surface 5a of the printed circuit board 5, an antenna ground 6 is formed by a conductor pattern (conductor film). Further, on this surface 5a, a connection portion 7 for electrically connecting the antenna ground 6 and the ground plane 4 is also formed by a conductor pattern. The antenna ground 6 is at the same potential as the ground plane 4 due to the connecting portion 7.

  A wireless communication unit 190 is fixed to the same surface 5 a of the substrate 5 as the antenna ground 6. Further, the antennas 110 </ b> A and 110 </ b> B are also fixed to the printed wiring board 5.

(Temperature monitoring process-antenna module side process)
Next, control executed by the CPU of the antenna module 100 (hereinafter referred to as an antenna module side CPU) 161 and the CPU of the communication ECU 200 (hereinafter referred to as ECU side CPU) 211 in order to monitor the temperature of the wireless communication unit 190 will be described.

  As shown in FIG. 4, when the power is turned on, the antenna module side CPU 161 performs a predetermined initialization process (step S1). This initialization process includes, for example, a timer reset. Subsequently, interrupt is permitted (step S2). In the present embodiment, the interrupt is permitted because the I / F unit 163 is configured to execute communication with the communication ECU 200 via the Ethernet cable 20 by interrupt processing.

  In step S3, the timer is reset. In step S4, it is determined whether or not a predetermined time has elapsed by referring to the timer. If this judgment is NO, it will progress to Step S5 and will perform wireless communication processing. The wireless communication processing includes, for example, control of the communication chip 150, communication channel setting, transmission / reception switching, transmission data set, and reception data reading. The antenna module side CPU 161 causes the communication chip 150 to transmit data at a predetermined duty ratio in data transmission. This duty ratio is changed according to the result of determining whether or not the temperature of the wireless communication unit 190 is abnormal by the process of FIG.

  If step S4 is YES, the process proceeds to step S6, and a sensor value (hereinafter, temperature sensor value) is read from the temperature sensor 192. In step S7, the temperature sensor value read in step S6 is written to a predetermined Ethernet output buffer in the interface adapter 160.

(Temperature monitoring process-ECU side process)
Next, FIG. 5 will be described. The ECU-side CPU 211 executes the process shown in FIG. 5 at regular intervals.

  In step S <b> 11, the above-described temperature sensor value is acquired from the antenna module side CPU 161 via the I / F unit 163, the Ethernet cable 20, and the I / F unit 250. In step S12, it is determined whether or not the temperature indicated by the temperature sensor value is equal to or higher than an abnormality determination threshold (hereinafter simply referred to as threshold) TH. This threshold value TH is set by reflecting the temperature of the wireless communication unit 190 in a normal state by the process of FIG.

  When this determination is NO, that is, when the temperature of the wireless communication unit 190 is lower than the threshold value TH, the process proceeds to step S13, and it is determined that the wireless communication unit 190 is normal. The determination result is stored in a predetermined storage unit in the calculation unit 211 such as the memory 212.

  Further, the abnormality determination A counter is cleared (step S14), and the abnormality determination B counter is also cleared (step S15).

  If the determination in step S12 is YES, that is, if the temperature of the wireless communication unit 190 is equal to or higher than the threshold value TH, the process proceeds to step S16. In step S16, it is further determined whether normal determination has been made so far. If this determination is YES, that is, if the determination is normal until the previous determination in step S12, the process proceeds to step S17. In step S17, the abnormality determination result of the wireless communication unit 190 is defined as abnormality determination A. The abnormality determination A is a state where the degree of abnormality is lightest among the three abnormal states.

  If judgment of step S16 is NO, it will progress to step S18. In step S18, it is determined whether or not the abnormality determination A has been determined so far. If step S18 is YES, it will progress to step S19 and will convert 1 into the abnormality determination A counter. Subsequently, in step S20, it is determined whether or not the abnormality determination A counter has reached a certain number of times. If the number of times has not yet reached (S20: NO), step S17 is executed. Therefore, the state determined as abnormality determination A is continued.

  If the abnormality determination A counter has reached a certain number of times, the determination in step S20 is YES, and the process proceeds to step S21. In step S21, an abnormality determination B is assumed.

  When step S18 is NO, the determination result so far is the abnormality determination B. If step S18 is NO, the process proceeds to step S22. In step S22, 1 is added to the abnormality determination B counter. Subsequently, in step S23, it is determined whether or not the abnormality determination B counter has reached a certain number of times. If the number of times has not yet reached (S23: NO), step S21 is executed. Therefore, the state determined as abnormality determination B is continued.

  If the abnormality determination B counter has reached a certain number of times, the determination in step S23 is YES and the process proceeds to step S24. In step S24, an abnormality determination C is assumed.

(Update of threshold TH)
The ECU-side CPU 211 periodically updates the threshold value TH by periodically executing the process of FIG. In step S31, the sensor value is taken from the outside air temperature sensor. In step S32, the sensor value is taken in from the sunshine sensor 43. In step S33, the sensor value is taken from the vehicle speed sensor 44. In step S34, the setting value of the transmission duty ratio is captured.

  In step S35, the threshold TH used in step S12 of FIG. 5 described above is set with reference to a preset table based on the data acquired in steps S31 to S34.

  FIG. 7 illustrates the above table. FIG. 7 shows four tables (A) to (D). Tables (A) and (B) are tables used when the outside air temperature is 30 degrees or higher. The difference between tables (A) and (B) is the transmission duty ratio. Table (A) has a transmission duty ratio of 5% or more, and table (B) has a transmission duty ratio of less than 5%.

  Tables (C) and (D) are tables used when the outside air temperature is less than 30 degrees, contrary to tables (A) and (B). The difference between the tables (C) and (D) is the transmission duty ratio, the difference between the tables (A) and (B), the transmission duty ratio of the table (C) is 5% or more, and the transmission of the table (D) is The duty ratio is less than 5%.

  Each of the tables (A) to (D) is a table in which the threshold value TH is determined by the vehicle speed and the amount of sunlight. In any table, the vehicle speed and the amount of sunlight are divided into two ranges. Specifically, in any table, the vehicle speed is divided into less than 30 km / h and more than 30 km / h, and the amount of sunshine is divided into large and small. Whether the amount of sunlight is large or small is determined by comparison with a reference amount of sunlight set in advance.

  In each table except the amount of sunshine “large” in the table (D), the threshold value TH is lower when the vehicle speed is high (30 km / h or more) than when the vehicle speed is low (less than 30 km / h). The reason why the threshold TH is lower when the vehicle speed is higher than when the vehicle speed is low is that the antenna module 100 is installed on the upper surface 2a of the vehicle roof 2, so that the higher the vehicle speed, the more the air is cooled by the outside air. This is because the effect is large.

  The reason why the threshold value is the same regardless of the vehicle speed for the amount of sunshine in the table (D) is that the lower limit value of the threshold value TH set in the case of the amount of sunshine is 80 degrees in this embodiment. is there.

  In each table, when the amount of sunlight is large, the threshold value TH is higher than when the amount of sunlight is small. This is because the antenna module 100 is installed at a position on the upper surface 2a of the vehicle roof 2 that is likely to become hot due to sunlight.

  Further, the comparison between the tables (A) and (C) and the comparison between the tables (B) and (D) in which the conditions of the outside temperature are different from each other and the conditions of the transmission duty ratio are the same as each other. In the case of 30 degrees or more), the threshold value TH is higher than in the case where the outside air temperature is low (less than 30 degrees). This is because the higher the outside air temperature, the higher the temperature of the wireless communication unit 190 is affected by the outside air temperature, even during normal times.

  Further, the transmission duty ratio is high from the comparison of the tables (A) and (B) and the comparison of the tables (C) and (D) where the conditions of the transmission duty ratio are different from each other and the conditions of the outside air temperature are the same. In the case of (5% or more), the threshold value TH is higher than in the case where the transmission duty ratio is low (less than 5%). This is because the higher the duty ratio, the higher the average transmission power, and the higher the transmission power, the more the wireless communication unit 190 generates heat even during normal operation.

  The threshold values TH in the table illustrated in FIG. 7 are set assuming the temperature of the wireless communication unit 190 in a normal state that is assumed due to the environmental temperature and heat generated by transmission. Note that the vehicle speed, the amount of sunlight, and the outside air temperature are environmental temperature parameters that affect the environmental temperature of the wireless communication unit 190. The transmission duty ratio is a transmission power related parameter. The environmental temperature parameter and the transmission power related parameter are temperature change parameters that affect the temperature change of the communication chip 150 at the normal time.

(Processing according to the abnormality judgment result)
The ECU side CPU 211 executes the process of FIG. 8 after executing the process of FIG. In step S41, it is determined whether or not transmission is prohibited. The transmission prohibited state is set in step S50 described later when it is determined that the abnormality determination C has the highest degree of abnormality.

  If transmission is prohibited (S41: YES), the process is terminated without transmission. If the transmission is not prohibited (S41: NO), the process proceeds to step S42, and the abnormality determination result is read.

  In step S43, it is determined whether or not the abnormality determination result read in step S42 is a normal determination. If it is normal determination, the process proceeds to step S44 to cancel the transmission condition restriction. The transmission condition restriction is a restriction for reducing the power consumption of the wireless communication unit 190 at the time of transmission. In this embodiment, the transmission duty ratio is reduced and the maximum transmission power is reduced.

  If it is determined in step S43 that the determination is not normal, the process proceeds to step S45. In step S45, it is determined whether or not the abnormality determination result is abnormality determination A. If the determination in step S45 is yes, the process proceeds to step S46, and the transmission duty ratio is reduced to a preset value lower than the transmission duty ratio at the time of normal determination.

  When it is determined in step S45 that the abnormality determination result is not abnormality determination A (S45: NO), the process proceeds to step S47, and it is determined whether or not the abnormality determination result is abnormality determination B. If the determination in step S47 is YES, the process proceeds to step S48, and the transmission duty ratio is reduced to a preset value lower than the transmission duty ratio at the time of normal determination. Note that the transmission duty ratio set in step S46 and the transmission duty ratio set in step S48 may be the same, or the transmission duty set in step S48 executed in the case of abnormality determination B with a higher degree of abnormality. The ratio may be a lower value.

  Furthermore, in step S49, the maximum transmission power is reduced to a preset value lower than the maximum transmission power at the time of normal determination.

  If it is determined in step S47 that the abnormality determination result is not the abnormality determination B (S47: NO), the abnormality determination result is the abnormality determination C having the highest degree of abnormality. In this case, the process proceeds to step S50, where transmission is prohibited, and in step S51, failure display is performed on a predetermined display unit.

  As described above, according to the present embodiment described above, the communication ECU 200 acquires the temperature change parameter for changing the temperature of the wireless communication unit 190 in the normal state (S31 to S34), and sets the threshold TH based on the temperature change parameter. Set (S35, S36). Therefore, the threshold value TH changes according to the temperature change when the wireless communication unit 190 is normal. The threshold TH set in this way is compared with the temperature detected by the temperature sensor 192 to determine whether or not the temperature of the wireless communication unit 190 is abnormal (S12). Therefore, it is possible to accurately determine whether or not the temperature of the wireless communication unit 190 that is modularized with the antennas 110A and 110B and installed on the outer surface of the vehicle roof 2 is abnormal.

  In this embodiment, not only whether the wireless communication unit 190 is abnormal or normal is determined, but when determining that the wireless communication unit 190 is abnormal, any of abnormality determinations A to C having different levels of abnormality levels. Is also determined (FIG. 5). And if it is except the abnormality determination C with the highest abnormality level, although transmission power is restrict | limited in order to suppress the temperature rise of the wireless communication part 190 (S46, S48, S49), transmission is not prohibited. Therefore, transmission can be continued as compared with the case where transmission is stopped immediately regardless of the degree of abnormality.

  Furthermore, in this embodiment, two abnormality levels, that is, abnormality determination A and abnormality determination B, are set as abnormality levels that continue transmission even if it is determined that there is an abnormality. If it is determined that the abnormality determination is A, the transmission duty ratio is merely reduced to a value lower than the normal transmission duty ratio, and the maximum transmission power is not reduced (S46). Therefore, even if it is determined that the wireless communication unit 190 is abnormal, if the abnormality determination result is the abnormality determination A, the transmission distance can be maintained.

  Further, in this embodiment, when it is determined as an intermediate level among the three abnormality determination levels, that is, abnormality determination B (S47: YES), the transmission duty ratio is made lower than normal (S48), and Then, the maximum transmission power is set lower than normal (S49). Therefore, in a situation where the degree of abnormality is higher than that of abnormality determination A, the temperature increase of wireless communication unit 190 can be suppressed more than when abnormality determination A is determined while continuing transmission.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, The following embodiment is also contained in the technical scope of this invention, and also the summary other than the following is also included. Various modifications can be made without departing from the scope.

  For example, in the above-described embodiment, the antenna module 100 includes the two antennas 110A and 110B in order to perform reception diversity in the inter-vehicle communication and the road-to-vehicle communication. However, the antenna module 100 performs the inter-vehicle communication and the road-vehicle communication. May be 1 or 3 or more (Modification 1). Moreover, you may perform only any one of vehicle-to-vehicle communication and road-to-vehicle communication (modification 2).

 In the above-described embodiment, the vehicle speed, the amount of sunshine, and the outside air temperature are acquired as the environmental temperature change parameters. However, the environmental temperature change parameter acquired to set the threshold value TH is one of the above three parameters. Any one or only two may be used (Modification 3). When the transmission power related parameter is used as the temperature change parameter for setting the threshold TH in addition to the environmental temperature change parameter, the threshold TH is determined from only the transmission power related parameter without using the environmental temperature change parameter. May be set (Modification 4). On the contrary, when the environmental temperature change parameter is used, the threshold value TH may be set only from the environmental temperature change parameter without using the transmission power related parameter (Modification 5). Further, as a transmission power related parameter, the maximum transmission power may be acquired instead of or in addition to the transmission duty ratio described above (Modification 6).

  Further, in the above-described embodiment, when the abnormal level is determined to be abnormal, it is determined which of the three abnormal levels is. However, only the abnormal level may be determined ( Modification 7). Further, the abnormality level may be determined by being divided into a plurality of numbers other than three (Modification 8).

  In the above-described embodiment, the Ethernet cable 20 is provided as an in-device communication unit that communicates between the antenna module 100 and the communication ECU 200. However, communication between the antenna module 100 and the communication ECU 200 is performed using other types of cables. You may make it like (Modification 9).

(Modification 10)
Communication between the antenna module 100 and the communication ECU 200 may be wireless communication. For example, in the vehicular wireless communication apparatus 1A shown in FIG. 9, the antenna module 100A and the communication ECU 200A include Bluetooth transmission / reception circuits 165 and 251 respectively. Then, the antenna module 100A and the communication ECU 200A communicate with each other by the Bluetooth transmission / reception circuits 165 and 251 provided therein. The Bluetooth transmission / reception circuits 165 and 251 correspond to the in-device wireless communication unit. In this modification, the power supply 240 is provided with a power supply line to supply power to the antenna module 100A.

DESCRIPTION OF SYMBOLS 1, 1A: Radio communication apparatus for vehicles 2: Vehicle roof 20: Ethernet cable (communication part in apparatus) 42: Outside temperature sensor 43: Sunlight sensor 44: Vehicle speed sensor 46: Other ECU groups 100, 100A: Antenna module 110A: Antenna 110B: Antenna 150: Communication chip (transmission / reception circuit) 151: Reception unit 152: Reception unit 153: Transmission unit 154: Baseband processing unit 160: Interface adapter 161: CPU 162: Memory 163: Interface unit 165: Bluetooth transmission / reception circuit ( 190: wireless communication unit 192: temperature sensor 200, 200A: communication ECU 210: calculation unit 211: CPU 212: memory Li 250: interface unit 251: Bluetooth transceiver circuit (device communication unit)

Claims (7)

An antenna (110A, 110B), a wireless communication unit (190) that performs wireless communication via the antenna, and a temperature sensor (192) that detects the temperature of the wireless communication unit are installed on the outer surface of the vehicle body. An antenna module (100, 100A);
A communication ECU (200, 200A) that is installed inside the vehicle and determines whether or not the temperature of the wireless communication unit is abnormal, and controls the wireless communication unit;
An in-device communication unit (20) that communicates between the antenna module and the communication ECU;
The communication ECU acquires at least one of an sunshine amount, a vehicle speed, and an outside temperature, which are environmental temperature change parameters that affect the environmental temperature of the wireless communication unit, and sets an abnormality determination threshold value based on the acquired environmental temperature change parameters. The vehicle is characterized by determining whether or not the temperature of the wireless communication unit is abnormal based on a comparison between the set abnormality determination threshold and the temperature of the wireless communication unit detected by the temperature sensor Wireless communication device (1, 1A). An antenna (110A, 110B), a wireless communication unit (190) that performs wireless communication via the antenna, and a temperature sensor (192) that detects the temperature of the wireless communication unit are installed on the outer surface of the vehicle body. An antenna module (100, 100A);
A communication ECU (200, 200A) that is installed inside the vehicle and determines whether or not the temperature of the wireless communication unit is abnormal, and controls the wireless communication unit;
An in-device communication unit (20) that communicates between the antenna module and the communication ECU;
The communication ECU acquires a temperature change parameter that affects a temperature change of the wireless communication unit in a normal state, sets an abnormality determination threshold based on the acquired temperature change parameter, sets the abnormality determination threshold, and the temperature Based on the comparison with the temperature of the wireless communication unit detected by the sensor, it is determined whether or not the temperature of the wireless communication unit is abnormal . It is also determined which one of them, and when the abnormal level is the highest, wireless transmission is stopped, and when the abnormal level is lower than the highest level, a transmission set in advance corresponding to the abnormal level A vehicle wireless communication device (1, 1A) characterized by performing control for reducing electric power . In claim 2 ,
The communication ECU obtains an environmental temperature change parameter that affects the environmental temperature of the wireless communication unit as the temperature change parameter. In claim 3 ,
The vehicular wireless communication apparatus, wherein the environmental temperature change parameter is at least one of a sunshine amount, a vehicle speed, and an outside air temperature. In any one of Claims 1-4 ,
The communication ECU acquires a transmission power related parameter related to the transmission power of the wireless communication unit as the temperature change parameter. In claim 5 ,
The vehicular wireless communication apparatus, wherein the transmission power related parameter is at least one of a transmission duty ratio and a maximum transmission power. In claim 2 ,
The communication ECU
The abnormality level of the wireless communication unit is determined by dividing the abnormality level into three,
If the abnormal level is the level indicating the most abnormal, wireless transmission is stopped,
If the abnormal level is the lowest level, the transmission duty ratio is lower than normal,
When the abnormal level is an intermediate level, the vehicular wireless communication apparatus is characterized in that the transmission duty ratio is lower than that in a normal state and the maximum transmission power is lower than that in a normal state.

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