JP5306866B2 - Vehicle detection device, vehicle detection system, and control method for vehicle detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress power consumption in a vehicle detector that transmits a detection result of vehicle existence to a master device. <P>SOLUTION: A vehicle detection system, which includes a plurality of slave devices, each corresponding to a vehicle detector, and a master device, transmits vehicle-detection data at a predetermined period (750 ms intervals) from each slave device to the master device, the data including the detection result of vehicle existence in the period. In the slave device, usually, the operation state of a slave-side controller is in a sleep state, and the power source of a slave-side wireless device is shut off. When the detection result of vehicle existence changes, while the slave-side controller shifts to an active state, the power source of the slave-side wireless device is turned on, and accumulation of detection-result data from the change point of the detection result is started. Moreover, when broadcast notification from the master device is received, the vehicle-detection data, including the detection-result data accumulated up to the point, are transmitted to the master device through the slave-side wireless device, and when the transmission is completed, the power source of the slave-side wireless device is shut off, and thereafter the slave-side controller shifts to the sleep state. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a vehicle detection device or the like that receives a detection signal from a vehicle detector and transmits vehicle detection data to a master unit.

  For example, a vehicle communication system including a wireless communication device that performs data communication with an in-vehicle communication device that is installed on a roadside and is mounted on a vehicle traveling on a road is known. In such a vehicle communication system, in order to reduce power consumption, a configuration is known in which a wireless communication device is activated to transmit data when detection of a vehicle entering an area where communication with a far-infrared sensor is possible. (For example, Patent Document 1).

JP 2007-200021 A

  Further, a vehicle detection system is known in which vehicle detection results are transmitted from a vehicle detection device that is installed on the roadside and detects a vehicle traveling on a road to, for example, a parent device installed at each intersection. Since the master unit needs to know the traffic volume of each traffic path that flows into the intersection in real time as much as possible, the vehicle detection results of each vehicle detection device installed in each inflow path are within an allowable delay time. Had to be sent to the parent machine. Therefore, it has been considered that a method of periodically transmitting the vehicle detection result from the vehicle detection device to the parent device is desirable. However, periodically communicating can be a method that is contrary to the suppression of power consumption in the vehicle detection device. The present invention has been made in view of the above circumstances, and an object thereof is to suppress power consumption in a vehicle detection device that transmits a vehicle presence / absence detection result to a parent device.

The first invention for solving the above-described problems is
A detection signal from a vehicle sensor (for example, the vehicle sensor 100 in FIGS. 1 and 12) is input, and vehicle detection data is transmitted via a wireless communication device (for example, the slave unit side wireless device 300 in FIGS. 1 and 12). Is a vehicle detection device (for example, the slave unit 10 of FIGS. 1 and 12) that transmits the master unit (for example, the master unit 50 of FIGS. 1 and 12),
Vehicle detection means for detecting the presence or absence of a vehicle based on the sense signal (for example, the vehicle detection unit 211 in FIG. 12);
A power-on means (for example, the power control unit 213 in FIG. 12) for turning on the power of the wireless communication device when a change occurs in the detection result by the vehicle detection means;
If the detection result by the vehicle detection means does not change within the periodic period for each predetermined period, the vehicle detection data for the period is not transmitted. Transmission control means (for example, the transmission control unit 212 in FIG. 12) that performs control to include the detection result of the periodic period by the vehicle detection means in the vehicle detection data and transmit it to the parent device after power is turned on by the power supply means. When,
A power shut-off means (eg, a power control unit 213 in FIG. 12) for shutting off the power of the wireless communication device after transmission of the vehicle detection data;
It is a vehicle detection apparatus provided with.

As another invention,
A method for controlling a vehicle detection device, comprising vehicle detection means for inputting a detection signal from a vehicle sensor and detecting the presence or absence of a vehicle based on the detection signal, and transmitting vehicle detection data to a master unit via a wireless communication device Because
A power-on step (for example, step A11 in FIG. 13) for powering on the wireless communication device when a change occurs in the detection result by the vehicle detection means;
If the detection result by the vehicle detection means does not change within the periodic period for each predetermined period, the vehicle detection data for the period is not transmitted. A transmission control step (for example, step A37 in FIG. 13) for performing control to include the detection result of the periodic period by the vehicle detection means in the vehicle detection data and transmit the result to the master unit after power-on by the power-on step;
A power shutdown step (eg, step B9 in FIG. 14) for shutting off the power of the wireless communication device after transmission of the vehicle detection data;
A control method for a vehicle detection device including the above may be configured.

  According to the first aspect of the invention, in the vehicle detection device that detects the presence or absence of the vehicle based on the sensing signal from the vehicle detector and transmits the vehicle detection result data to the master unit via the wireless communication device, If there is no change in the vehicle presence / absence detection result for each cycle period, the vehicle detection data in the cycle period is not transmitted, and if the detection result changes, the wireless communication device is turned on. Thus, the vehicle detection data in the period is transmitted, and the power of the wireless communication device is shut off after the transmission. That is, the vehicle detection data is transmitted only when a change in the vehicle presence / absence detection result occurs, and the power of the wireless communication device is turned on when the vehicle detection data is transmitted, and is shut off at other times. As a result, the power consumption of the vehicle detection device can be reduced, and the detection result of the presence or absence of the vehicle can be determined and recognized almost in real time for the master unit, although there is a delay of every cycle period.

As a second invention, the vehicle detection device of the first invention,
The operation state of the own apparatus is shifted from the sleep state in which the operation of the vehicle detection unit is valid to the active state triggered by a change in the detection result by the vehicle detection unit, and the transmission control unit You may comprise the vehicle detection apparatus further provided with the operation state control means (For example, transmission control part 212 of FIG. 12; step B11 of FIG. 14) which transfers to the said sleep state after transmission of vehicle detection data.

  According to the second aspect of the invention, the operation state of the vehicle detection device shifts from the sleep state to the active state triggered by the change in the vehicle presence / absence detection result, and the sleep state after the vehicle detection data is transmitted. Migrate to In the sleep state, less power is consumed than in the active state. Thereby, the power consumption in the vehicle detection device can be further reduced.

As a third invention, the vehicle detection device of the first or second invention,
It is configured to be able to input sensing signals from a plurality of the vehicle detectors provided for each traveling lane,
The vehicle detection means detects the presence or absence of a vehicle for each of the sensing signals from the plurality of vehicle detectors,
The power-on means turns on the power when any of the vehicle presence / absence detection results by the vehicle detection means changes,
The transmission control unit does not transmit the vehicle detection data for the period when the detection result of the presence or absence of the vehicle by the vehicle detection unit does not change, and when any changes, Transmitting the vehicle detection data for a period period;
A vehicle detection device may be configured.

  According to the third aspect of the present invention, power consumption can be reduced even for a vehicle detection device to which detection signals from a plurality of vehicle detectors provided for each lane are input. In this case, when any of a plurality of vehicle presence / absence detection results detected for each of the sensing signals from the plurality of vehicle detectors changes, the wireless communication device is turned on and vehicle detection data is transmitted. If none of the vehicle presence / absence detection results change, vehicle result data is not transmitted, and the wireless communication device is not turned on.

As a fourth invention, there is provided a vehicle detection device according to any one of the first to third inventions,
The transmission control means detects change time information (for example, “the number of idle bits” and “the number of effective bits” in FIG. 4) indicating the time when the detection result by the vehicle detection means has changed during the period. Send it in the data,
A vehicle detection device may be configured.

  According to the fourth aspect of the invention, the change timing information indicating the time when a change has occurred in the vehicle presence / absence detection result in the period is included in the vehicle detection data and transmitted. Thus, in the base unit, when the presence / absence of the vehicle is developed in time series based on the received vehicle detection data, only the portion corresponding to the change timing of the detection result indicated by the change timing information is extracted from the data. Since it is good, the time taken to expand the detection result can be shortened.

Specifically, for example, as a fifth invention, the vehicle detection device of the fourth invention,
A change that counts a time interval (for example, “number of effective bits” in FIG. 4) from the first change of the detection result by the vehicle detection unit to the last change in the cycle period for each cycle period. It further comprises time counting means (for example, the transmission control unit 212 in FIG. 12),
The transmission control means transmits the time interval counted by the change time counting means included in the vehicle detection data as the change time information,
A vehicle detection device may be configured.

  According to the fifth aspect of the present invention, the time interval from the first change of the vehicle presence / absence detection result to the last change in the cycle period is the vehicle detection result data as the change timing information. To be sent. As a result, the master unit has only to extract the data corresponding to the time interval indicated by the change timing information from the time-series data indicating the presence or absence of the vehicle.

Further, for example, as a sixth invention, the vehicle detection device of the fourth or fifth invention,
Initial change waiting time counting means for counting the time interval from the start of the periodic period to the first change of the detection result by the vehicle detection means (for example, “the number of idle bits” in FIG. 4) for each periodic period. (For example, the transmission control unit 212 in FIG. 12)
The transmission control means transmits the time interval counted by the initial change waiting time counting means included in the vehicle detection data as the change timing information.
A vehicle detection device may be configured.

  According to the sixth aspect of the invention, for each cycle period, the time interval from the start of the cycle period to the first change in the vehicle presence / absence detection result is transmitted as change timing information included in the vehicle detection data. This eliminates the need for the base unit to read data corresponding to the time until the first change indicated by the change timing information from the time-series data indicating the presence or absence of the vehicle.

And as 7th invention, the vehicle detection apparatus of any one of the 1st-6th invention,
A master unit that wirelessly communicates with each of the plurality of vehicle detection devices and receives the vehicle detection data from each vehicle detection device;
You may comprise the vehicle detection system which comprises.

Furthermore, a plurality of vehicle detection devices according to any one of the fourth to sixth inventions and a master unit that wirelessly communicates with each of the plurality of vehicle detection devices and receives the vehicle detection data from each vehicle detection device are provided. A vehicle detection system,
The base unit is
Using the change timing information included in the vehicle detection data, and means for developing from the vehicle detection data the presence or absence of the vehicle detected by the vehicle detection device during the period.
A vehicle detection system may be configured.

An installation example of a vehicle detection system. Explanatory drawing of the communication procedure between a main | base station and each subunit | mobile_unit. An example of the detection result of the vehicle presence or absence in a subunit | mobile_unit. The data structural example of vehicle detection data. The time chart explaining operation | movement of a subunit | mobile_unit. The time chart explaining operation | movement of a subunit | mobile_unit. The time chart explaining operation | movement of a subunit | mobile_unit. The time chart explaining operation | movement of a subunit | mobile_unit. The time chart explaining operation | movement of a subunit | mobile_unit. The time chart explaining operation | movement of a subunit | mobile_unit. The time chart explaining operation | movement of a subunit | mobile_unit. The functional block diagram of a vehicle detection system. The flowchart of the transmission control process performed with a subunit | mobile_unit. The flowchart of the transmission standby process performed during a transmission control process. The flowchart of the main | base station side process performed with a main | base station. The time chart explaining operation | movement of the subunit | mobile_unit which has a some vehicle detector. The data structural example of the vehicle detection data transmitted from the subunit | mobile_unit which has a some vehicle detector.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. However, the applicable embodiment of the present invention is not limited to this.

[System configuration]
FIG. 1 is a diagram illustrating an installation example of the vehicle detection system 1 of the present embodiment. According to the figure, the vehicle detection system 1 is installed and configured at each intersection, for example, and includes a plurality of (four in the figure) slave units 10 and a master unit 50 which are vehicle detection devices.

  The subunit | mobile_unit 10 is installed targeting each traffic path which forms an intersection, and has the vehicle detector 100, the subunit | mobile_unit side control machine 200, and the subunit | mobile_unit side radio | wireless machine 300. FIG. The slave-side controller 200, the vehicle detector 100, and the slave-side radio device 300 are connected by wired cables, and data can be transmitted and received. Moreover, this subunit | mobile_unit 10 operate | moves using a solar cell (not shown) as a power supply.

  The vehicle detector 100 is installed above a pillar installed on the roadside so as to overlook a sensing target lane from above. The vehicle detector 100 is, for example, a far-infrared type using a thermopile element, and outputs a sensing signal having a level corresponding to the temperature of the sensing target to the slave unit-side controller 200 as needed.

  The slave-side controller 200 is installed below the pillar on which the vehicle detector 100 is installed, detects the presence or absence of a vehicle in the corresponding lane based on the detection signal from the vehicle detector 100, and “vehicle detection data”. Is transmitted to the parent device 50 via the child device-side wireless device 300.

  Slave device side wireless device 300 is installed above the pillar on which vehicle sensor 100 is installed, and performs predetermined wireless communication (for example, SS (Spread Spectrum) wireless communication) with parent device side wireless device 600. .

  The parent device 50 includes a parent device-side controller 500 and a parent device-side wireless device 600. For example, the parent device-side wireless device 600 is installed above a pillar installed near an intersection, and the parent device is below. A side controller 500 is installed. The master-side controller 500 and the master-side radio device 600 are connected by a wired cable so that data can be transmitted and received.

  Based on the vehicle detection data received from each of the slave units 10 via the slave unit side radio device 300, the master unit side controller 500 aggregates the detection results of the presence or absence of vehicles for each traffic path. The aggregated data is transmitted to, for example, a centralized management center connected via a predetermined communication line.

  The base-side radio device 600 performs predetermined radio communication (for example, SS radio communication) with each of the slave-side radio devices 300.

  In addition, although the figure has shown the case where the four subunit | mobile_unit 10 is installed targeting the cross intersection comprised of four traffic paths, the shape of an intersection and the installation number of the subunit | mobile_unit 10 are shown to this. Not exclusively.

[principle]
First, communication procedures between the parent device 50 and the child device 10 will be described. FIG. 2 is a diagram illustrating a communication procedure between the parent device 50 and the child device 10. The figure shows a case where wireless communication is performed between one parent device 50 and four child devices 10. In addition, the data transmission timings of the parent device 50 and each child device 10 are shown with the horizontal direction as the time axis.

  As shown in the figure, the parent device 50 transmits a broadcast notification to all the child devices 10. This broadcast notification is repeatedly transmitted at a predetermined transmission time interval (this embodiment will be described as “750 ms interval” as an example). When each slave unit 10 receives the broadcast notification, the slave unit 10 transmits the vehicle detection data to the master unit 50 after a predetermined transmission standby time Tw determined for the slave unit 10 has elapsed.

  The transmission standby time Tw is a time for designating the transmission timing of the vehicle detection data from the slave unit 10, and is predetermined for each slave unit 10 as an elapsed time from the reception time point of the broadcast notification. This transmission standby time Tw is set so that the vehicle detection data of each slave unit 10 is not transmitted at the same time so that the vehicle detection data transmission timings of each slave unit 10 do not overlap. Transmission order, the data length of the vehicle detection data, the communication speed by wireless communication, and the like. The transmission time interval of the broadcast notification from the parent device 50 is determined as a time interval sufficient to complete the transmission of the vehicle detection data from all the child devices 10 and the reception by the parent device 50.

  Base unit 50 broadcasts a broadcast notification to each slave unit 10 at a predetermined transmission interval (750 ms). The slave unit 10 periodically receives a broadcast notification from the master unit 50 at this transmission interval, and includes a vehicle presence / absence detection result in the periodic period for each reception cycle period of the broadcast notification. The detection data is transmitted to the parent device 50.

  FIG. 3 is a diagram illustrating an example of a vehicle presence / absence detection result. As shown in the figure, the vehicle presence / absence detection result based on the sensing signal from the vehicle detector 100 is binary of “H (1)” indicating the presence of the vehicle and “L (0)” indicating the absence of the vehicle. Consists of. The detection result data is a time series obtained by sampling the detection result signal at a predetermined sampling period Ts (in this embodiment, described as “50 ms” as an example), and is data. It consists of 15 bits per cycle.

  FIG. 4 is a diagram illustrating an example of a data configuration of the vehicle detection data 20 transmitted from the child device 10 to the parent device 50. As shown in the figure, the vehicle detection data 20 is fixed-length data including an idle bit number 21, effective bit number 22, and detection result accumulation data 23.

  The idle bit number 21 and the effective bit number 22 are data indicating the change timing of the vehicle presence / absence detection result in the corresponding cycle period. That is, the idle bit number 21 represents a time interval from the start of the periodic period to the first change time of the vehicle presence / absence detection result in the periodic period. Specifically, it is the number of bits from the first bit of the period to the first change bit of the detection result data. The effective bit number 22 represents a time interval from the first change time point to the last change time point of the detection result in the period. Specifically, it is the number of bits from the first change bit to the last change bit of the detection result data.

  The detection result accumulation data 23 is data of detection results from the first change point of the vehicle detection result in the cycle period to the end of the cycle period. Specifically, it is time-series data obtained by accumulating from the first change bit of the detection result data in the period to the last bit of the period.

  In this embodiment, the subunit | mobile_unit 10 normally cuts off the power supply of the subunit | mobile_unit side radio | wireless machine 300 for power saving. Then, when transmitting the vehicle detection data to the master unit 50, the power of the slave unit side radio device 300 is turned on (ON), and when the transmission of the vehicle detection data is completed, the power source is turned off again. Basically, the transmission of the vehicle detection data from the child device 10 to the parent device 50 is performed only in the periodic period in which the detection result of the presence / absence of the vehicle has changed, and is not performed in the periodic period in which the detection result has not changed. .

  Furthermore, the slave-side controller 200 normally sets the operation state to the sleep state (standby state). In the sleep state, it is possible to determine the detection result of the presence or absence of the vehicle based on the sensing signal from the vehicle detector 100 and to determine the change in the detection result. Then, when the change in the detection result of the presence / absence of the vehicle is determined, the operation state shifts to the active state, and when the transmission of the detection result data is completed, the operation state shifts again.

  Next, the operation of the slave unit 10 will be described in detail with a specific example. FIG. 5 is a time chart for explaining the operation of the child device 10 and shows the operation in one cycle (750 ms). In the figure, the horizontal direction is time, and the vehicle presence / absence detection result, the number of idle bits, the number of accumulated bits, and the number of effective bits are shown in order from the top. However, as an initial state, it is assumed that the operation state of the slave unit side controller 200 is the sleep state, and the power source of the slave unit side radio device 300 is cut off.

  The subunit | mobile_unit side controller 200 detects the presence or absence of a vehicle by comparing the sensing signal from the vehicle detector 100 with a predetermined threshold value. When the change (rising / falling) of the vehicle presence / absence detection result is recognized, the operation state shifts from the sleep state to the active state, and then the power of the slave unit side radio device 300 is turned on. Also, accumulation of detection result data is started from the bit where the detection result has changed. Further, counting of “the number of accumulated bits” and “the number of idle bits” is started from the bit whose detection result has changed. The “accumulation bit number” is “0” as an initial value, and “1” is added every time the detection result data is accumulated. The initial value of “idle bit number” is “20”, and “1” is subtracted every time detection result data is accumulated. In addition, when the “effective bit number” is “1”, the number of accumulated bits when the detection result changes is set.

  When a broadcast notification is received from the parent device 50, vehicle detection data for the period until the broadcast notification is received is generated, and the vehicle detection data is transmitted at a predetermined timing. 50. Specifically, the transmission is performed after a total time of a transmission standby time Tw determined for each slave unit 10 and a transmission allowance time Te (for example, 250 ms) for the broadcast notification has elapsed. The transmission allowance time Te is determined to be longer than the time Th required for the modem heat run of the handset device 300. In the figure, the transmission standby time Tw of the child device 10 is “0”, and the vehicle detection data is transmitted after the transmission allowance time Te has elapsed from the reception of the broadcast notification. The vehicle detection data is generated as data including the number of idle bits, the number of effective bits, and detection result accumulation data at the time when the broadcast notification is received. Then, when the transmission of the vehicle detection data ends, the processing unit 210 shuts off the power supply of the slave unit side wireless device 300 and then shifts to the sleep state.

In the figure, the detection result changes from “L (0)” to “H (1)” at the fifth bit (rise). That is, accumulation of detection result data and counting of the number of idle bits and the number of accumulated bits are started from the fifth bit. At the time of receiving the broadcast notification, the detection result accumulation data is data of 11 bits in total from the 5th bit to the 15th bit of the detection result. Further, the number of idle bits is “ 9 ”, and the number of effective bits is “1”. Then, vehicle detection data including the detection result accumulation data, the number of idle bits, and the number of effective bits is transmitted to the parent device 50.

FIG. 6 is a time chart for explaining the operation of the child device 10 in the next cycle (cycle 2) of FIG. In FIG. 6, the vehicle presence / absence detection result changes from “H (1)” to “L (0)” (falling) in the second bit. That is, accumulation of detection result data is started from the second bit, and counting of the number of idle bits and the number of accumulated bits is started. Also, the number of effective bits is set to “1”. When the broadcast notification is received, the detection result accumulated data is 14-bit data in total from the second bit to the 15th bit of the detection result.
Further, the number of idle bits is “6”, and the number of effective bits is “1”.

  On the other hand, in the parent device 50, the detection result data of the child device 10 in the cycle (cycle 1) is restored based on the vehicle detection data transmitted from the child device 10 after the end of the previous cycle (cycle 1). The That is, first, the value of the last bit of the restored detection result data is continued by the number of idle bits (idle). Next, the detection result accumulated data is expanded from the first bit by the number of valid bits, and is used as subsequent detection result data (valid). And the value of the bit immediately before it is continued for the remaining bits which are less than 15 bits. Thus, in the main | base station 50, the detection presence or absence of the vehicle in the newest subunit | mobile_unit 10 can be obtained for every period period.

  In FIG. 6, as vehicle detection data, data including the number of idle bits “9”, the number of valid bits “1”, and 11-bit detection result accumulation data “111...” Is received. In other words, the detection result data to be restored has the value “0” of the immediately preceding bit from the first bit to the ninth bit as idle bits. Next, the 10th bit is set to the value “1” of the first bit of the detection result accumulation data as a valid bit. From the 11th bit to the 15th bit, the value “1” of the immediately preceding 10th bit is set. That is, the restored detection result data of the cycle (cycle 1) is “0” from the 1st bit to the 9th bit, and “1” from the 10th bit to the 15th bit.

  FIG. 7 is a time chart for explaining the operation of the slave unit 10 in the next cycle of FIG. In FIG. 7, the vehicle presence / absence detection result remains “1” and does not change. Accordingly, the vehicle detection data is not transmitted from the child device 10 to the parent device 50.

  On the other hand, based on the vehicle detection data transmitted from the slave unit 10 after the end of the previous cycle, the master unit 50 restores the detection result data of the slave unit 10 in the cycle (cycle 2). That is, in FIG. 7, data including the idle bit number “6”, the effective bit number “1”, and the 14-bit detection result accumulation data “000...” Is received as the vehicle detection data. In other words, the restored detection result data is the value of the last restored bit, that is, the value “1” of the 15th bit of the cycle immediately before the restoration, from the first bit to the sixth bit. Next, the seventh bit is set to the value “0” of the first bit of the detection result accumulated data. The 8th to 15th bits are set to the value “0” of the immediately preceding 7th bit. Therefore, the restored detection result data of the cycle (cycle 2) is “1” from the 1st bit to the 6th bit, and “0” from the 7th bit to the 15th bit.

  The base unit 50 does not receive the vehicle detection data of the next cycle (cycle 3). However, the vehicle detection data is not received in the cycle (cycle 3) because the vehicle detection data is not received. It can be determined that there is no change.

  FIG. 8 is a time chart showing three consecutive periods shown in FIGS.

  FIG. 9 is a time chart showing another operation example in the slave unit 10 and shows two consecutive cycles. In FIG. 9, in the first cycle (cycle 1), the vehicle presence / absence detection result changes a plurality of times. That is, as a first change, the detection result changes from “0” to “1” at the third bit (rise). As a second change, the detection result changes from “1” to “0” at the fifth bit. As the third change, the detection result changes from “0” to “1” at the eighth bit. As a fourth change, the detection result changes from “1” to “0” at the 10th bit.

  In this case, accumulation of detection result data is started and measurement of the number of idle bits and the number of effective bits is started at the bit where the detection result has changed first. Also, the number of effective bits is set to “1”. For each change after the second time, the number of effective bits in the changed bits is updated to the number of accumulated bits.

  That is, in the figure, accumulation of detection result data is started from the third bit, and measurement of the number of idle bits and the number of accumulated bits is started. Also, the number of effective bits is set to “1”. In addition, the effective number of bits is updated to “3” at the fifth bit that has changed the second time, and the effective bit number is updated to “6” at the eighth bit that has changed the third time. In the 10th bit, the number of effective bits is updated to “8”. Therefore, at the time of receiving the broadcast notification, the number of idle bits is “7” and the number of valid bits is “8”. The detection result accumulation data is 13-bit data in total from the third bit to the 15th bit of the detection result. Then, the vehicle detection data including the number of idle bits, the number of effective bits, and the detection result accumulation data is transmitted to the parent device 50.

  Subsequently, in the next cycle (cycle 2), the vehicle presence / absence detection result does not change. Therefore, the vehicle detection data is not transmitted from the child device 10 to the parent device 50.

  On the other hand, in the parent device 50, the detection result data in the corresponding cycle (cycle 1) is restored based on the vehicle detection data received from the child device 10. That is, data including the idling bit number “7”, the effective bit number “8”, and the 13-bit detection result accumulation data “11000110...” Is received as the vehicle detection data. Therefore, the detection result data to be restored is “0” from the first bit to the seventh bit. The 8th to 15th bits are “11000110” obtained by expanding 8 bits from the head of the detection result accumulation data.

  FIG. 10 is a time chart showing another operation example in the slave unit 10, and shows three consecutive cycles. In the figure, in the first cycle (cycle 1), the detection result changes from “0” to “1” at the 15th bit (rise). That is, counting of the number of idle bits and the number of effective bits is started at the 15th bit, and accumulation of detection result data is started. In the 15th bit, a broadcast notification is received. Therefore, the number of idle bits at the time of receiving the broadcast notification is “19”, and the number of valid bits is “1”. The detection result accumulation data is 1-bit data “1” of the 15th bit.

  Here, considering the case where the detection result data of the cycle (cycle 1) is restored, after the last value is continued for 19 bits (idle), the first 1-bit data of the detection result accumulation data is developed. . That is, the restored detection result data is 20 bits. This exceeds 15 bits corresponding to one period. In this way, when the number of bits of detection result data to be restored exceeds the number of bits for one cycle, the initial value of the number of idle bits in the next cycle is decreased by the number of bits exceeding that one cycle.

That is, the number of adjustment bits Δn is calculated according to the following equation (1).
Δn = (Number of idle bits + number of effective bits) −15 ... (1)
The initial value of the number of idle bits in the next cycle is set to “20−Δn”. If the sum of the number of idle bits and the number of valid bits at the time of receiving the broadcast notification does not exceed “15”, the adjustment bit number Δn is set to “0”.

In the figure, in the first cycle (cycle 1), the number of idle bits at the time of receiving the broadcast notification is “19”, and the number of valid bits is “1”. Therefore, the number of adjustment bits Δn is “5 (= (19 + 1) −15 )”.

  Subsequently, in the next cycle (cycle 2), the vehicle presence / absence detection result changes from “1” to “0” (falling) at the 14th bit. That is, accumulation of detection result data is started from the 14th bit, and counting of the number of idle bits and the number of effective bits is started. At this time, since the number of adjustment bits Δn in the immediately preceding cycle (cycle 1) was “5”, the number of idle bits is counted with “15 (= 20−5)” as an initial value.

  The number of idle bits at the time of receiving the broadcast notification is “13”, and the number of valid bits is “1”. The detection result accumulation data is 2-bit data “00” from the 14th bit to the 15th bit. Here, the total number of idle bits and effective bits is “14” and does not exceed “15”. Therefore, the adjustment bit number Δn is “0” in the next cycle.

  On the other hand, in base unit 50, detection result data of the corresponding cycle (cycle 1) is restored based on the vehicle detection data received from slave unit 10. That is, as the vehicle detection data, data including the idle bit number “19”, the effective bit number “1”, and the 2-bit detection result accumulation data “00” is received. Therefore, the detection result data to be restored has 19 bits from the first bit to the 19th bit as the immediately preceding value “0” as idle bits, and then the first bit of the detection result accumulation data as a valid bit. This is expanded to the 20th bit. In other words, 20-bit data is restored, but this exceeds 15 bits corresponding to 1 bit. In this way, when the restored detection result data exceeds 15 bits for one period, the excess data is carried over to the next period. That is, in the case of the same figure, the last 5 bits of the restored detection result data are carried over to the next cycle (cycle 2).

  In the last cycle (cycle 3), the vehicle detection signal does not change. Accordingly, the vehicle detection data is not transmitted from the child device 10 to the parent device 50.

  On the other hand, in base unit 50, detection result data of the corresponding cycle (cycle 2) is restored based on the vehicle detection data received from slave unit 10. That is, as the vehicle detection data, data including the idling bit number “13”, the effective bit number “1”, and the 2-bit detection result accumulation data “00” is received.

  Here, when the detection result data restored from the previous cycle (cycle 1) is carried over, the detection result data restored based on the received vehicle detection data is data following the carried over data. It is said.

  That is, in the figure, the detection result data of 5 bits is carried over from the previous cycle (cycle 1), and the detection result data restored based on the received vehicle detection data is the cycle (cycle 2). The data after the 6th bit. That is, as idle bits, 13 bits from the 6th bit to the 18th bit of the cycle (cycle 2) are set to the value “1” of the 5th bit which is the immediately preceding bit. Next, as a valid bit, the 19th bit is set to the value “0” of the first 1 bit of the detection result accumulation data. Also in this case, the restored detection result data exceeds 15 bits corresponding to one cycle. For this reason, the last restored 4-bit data is carried over to the next cycle (cycle 4).

  FIG. 11 is a time chart showing another operation example in the slave unit 10 and shows three consecutive cycles. In the figure, in the first cycle (cycle 1), the detection result changes from “0” to “1” (rise) at the 11th bit. That is, from the 11th bit, accumulation of detection result data, counting of idle bits and accumulated bits are started. At the time of receiving the broadcast notification, the number of idle bits is “15” and the number of valid bits is “1”. That is, the total number of idle bits and effective bits is “16 (= 15 + 1)”, which exceeds “15”. Accordingly, the number of adjustment bits Δn is “1 = (16−15)”.

  In the next cycle (cycle 2), the detection result changes from “1” to “0” (falling) at the 14th bit. That is, accumulation of detection result data, counting of the number of idle bits and the number of accumulated bits are started from the 14th bit. At this time, since the number of adjustment bits Δn in the immediately preceding cycle (cycle 1) is “1”, the number of idle bits is counted with “19 (= 20−1)” as an initial value. At the time of receiving the broadcast notification, the number of idle bits is “17” and the number of valid bits is “1”. That is, the total number of idle bits and effective bits is “18”, which exceeds “15”. Therefore, the number of adjustment bits Δn is “3 = (18−15)”.

  On the other hand, in the parent device 50, the detection result data in the corresponding cycle (cycle 1) is restored based on the vehicle detection data received from the child device 10. That is, as the vehicle detection data, data including the idle bit number “15”, the effective bit number “1”, and the 5-bit detection result accumulation data “111...” Is received. Accordingly, in the detection result data of the period to be restored (period 1), 15 bits from the 1st bit to the 15th bit are set to the previous value “0” as idle bits, and the 16th bit is set as the valid bit. The value of the first 1 bit of the detection result accumulated data is set to “1”. That is, the restored detection result data is 16-bit data, and the last 1-bit data exceeding 15 bits for one cycle is carried over to the next cycle (cycle 2).

  In the next cycle (cycle 3), the base unit 50 restores the detection result data of the corresponding cycle (cycle 2) based on the vehicle detection data received from the handset 10. That is, as the vehicle detection data, data including the idling bit number “17”, the effective bit number “1”, and the 2-bit detection result accumulation data “00” is received. Also, 1-bit detection result data is carried over from the previous cycle (cycle 1). For this reason, the detection result data to be restored is data subsequent to the detection result data carried over from the previous cycle.

  That is, the first 1 bit of the corresponding cycle (cycle 2) is data “1” carried over from the previous cycle (cycle 1). Then, the second and subsequent bits of the cycle (cycle 2) are data restored based on the vehicle detection data. That is, 17 bits from the 2nd bit to the 18th bit as the idle bits become the value “1” of the 1st bit which is the immediately preceding bit, and the 19th bit as the effective bit is the head of the detection result accumulation data. The bit value is “0”. Also in this case, the restored detection result data exceeds 15 bits for one cycle, and the extra 4 bits, that is, the last 4 bits of the restored detection result data, is the next cycle (cycle). Carried over to 3).

[Function configuration]
FIG. 12 is a block diagram showing a functional configuration of the vehicle detection system 1. As shown in the figure, the vehicle detection system 1 includes a parent device 50 and a plurality of child devices 10.

  The subunit | mobile_unit 10 has the vehicle sensor 100, the subunit | mobile_unit side controller 200, the subunit | mobile_unit side radio | wireless machine 300, and the power supply part 400. FIG.

  The subunit | mobile_unit side controller 200 has the process part 210 and the memory | storage part 220 as a function part. The processing unit 210 is realized by an arithmetic circuit including a CPU and various processors, for example, and based on programs and data stored in the storage unit 220, instructions and data transfer to each unit constituting the slave unit side controller 200 are performed. Etc. to perform overall control of the slave side controller 200. In addition, the processing unit 210 includes a vehicle detection unit 211, a transmission control unit 212, and a power supply control unit 213.

  The vehicle detection unit 211 detects the presence / absence of a vehicle in the target lane based on the detection signal input from the vehicle detector 100. Specifically, the difference between the signal level of the sensing signal and a predetermined road surface level is calculated, and if this level difference is equal to or greater than a predetermined threshold for determining that there is a vehicle, it is detected that “the vehicle is present” and is less than the threshold Then, “no vehicle” is detected.

  The transmission control unit 212 performs transmission control processing according to the transmission control program 221, and transmits vehicle detection data including the vehicle presence / absence detection result by the vehicle detection unit 211 to the parent device 50 via the child device side radio device 300. Send.

  In the transmission control process, when a change in the vehicle presence / absence detection result by the vehicle detection unit 211 is monitored and a change in the detection result is determined, the operation state of the own device is shifted from the sleep state to the active state. Further, the power supply control unit 213 is made to turn on the power of the handset side wireless device 300. Then, accumulation of detection result data is started from the bit whose detection result has changed, and counting of the number of idle bits and the number of accumulated bits is started. At this time, the idle bit number has an initial value “20−Δn”, and the accumulated bit number has an initial value “0”. Also, the effective bit number is set to “1”. Here, the detection result accumulation data, the idle bit number, the accumulation bit number, the effective bit number, and the adjustment bit number Δn are stored as the count data 223. After that, if the detection result changes again before receiving the broadcast notification, the accumulated bit number at that time is updated as the effective bit number.

  Then, when a broadcast notification is received from the parent device 50 via the child device side wireless device 300, vehicle detection data including the number of idle bits, the effective bit number, and the detection result accumulation data at that time is generated. The generated vehicle detection data is stored as transmission vehicle detection data 222.

  Also, the number of adjustment bits Δn is updated. That is, if the total of the number of idle bits and the number of effective bits is 15 bits or less for one cycle, the number of adjustment bits Δn is set to “0”, and if the total number of bits exceeds 15 bits, the 15 bits The number of bits exceeding the threshold value is defined as the number of adjustment bits Δn.

  Subsequently, after the total time of the specified transmission allowance time Te and the transmission standby time Tw determined for the slave unit 10 has elapsed since the reception of the broadcast notification, the generated vehicle detection data is transmitted to the slave unit side radio. The data is transmitted to the parent device 50 via the device 300. When the transmission of the vehicle detection data is completed, the power supply control unit 213 causes the power supply of the slave unit side wireless device 300 to be cut off, and the operation state of the own device is shifted from the active state to the sleep state.

  The power supply control unit 213 controls the power-off / on of the slave unit side wireless device 300 according to the instruction of the transmission control unit 212.

  The slave-side controller 200 is realized by a wireless communication device such as SS wireless, for example, and performs predetermined wireless communication with an external device (mainly, the master-side wireless device 600).

  The storage unit 220 is realized by a storage device such as a hard disk, a ROM, or a RAM, and a system program for the processing unit 210 to control the slave-side controller 200 in an integrated manner, a program and data for realizing various functions. And the like, and is used as a work area of the processing unit 210, and temporarily stores calculation results executed by the processing unit 210 according to various programs. In the present embodiment, the storage unit 220 stores a transmission control program 221 for causing the processing unit 210 to function as the transmission control unit 212 as a program, and includes transmission vehicle detection data 222 and count data as data. 223 is stored.

  The parent device 50 includes a parent device-side controller 500 and a parent device-side radio device 600. The base-side controller 500 broadcasts a broadcast notification to all the slave units 10 via the base-side radio device 600 at a predetermined transmission interval (750 ms interval).

  Further, in response to the broadcast notification, the vehicle detection data transmitted from the slave unit 10 is received via the master unit side radio device 600, and the vehicle in the slave unit 10 is received based on the received vehicle detection data. Restore the presence / absence detection result data. Specifically, as the detection result data of the cycle, first, the value of the last restored bit is continued by the number of idle bits included in the received vehicle detection data (idle). Next, the data of the effective number of bits included in the vehicle detection data is expanded from the first bit of the detection result accumulation data included in the vehicle detection data, and the subsequent data is used. For bits that are less than 15 bits for one cycle, the value of the last restored bit is continued until the last bit of the cycle. When the restored detection result data exceeds 15 bits for one cycle, the excess data is carried over to the next cycle.

  The base-side radio device 600 is realized by a radio communication device such as SS radio, for example, and performs predetermined radio communication with an external device (mainly, the slave-side radio device 300).

[Process flow]
FIG. 13 is a flowchart for explaining the flow of transmission control processing executed by the slave-side controller 200. However, as an initial state, it is assumed that the operation state of the slave unit side controller 200 is “sleep state” and the power source of the slave unit side radio device 300 is cut off.

  According to the figure, the transmission control unit 212 first performs an initial setting (step A1). That is, the accumulated bit number is set to an initial value “0”, the idle bit number is set to “20”, and the effective bit number is set to “1”. Further, the detection result accumulation data is cleared and the accumulation flag is set to “0”. This accumulation flag is a flag indicating whether or not the vehicle detection result has changed in the period.

  Thereafter, the process of Loop A is repeatedly performed at a predetermined sampling interval (50 ms interval). In loop A, the detection result of the presence or absence of the vehicle by the vehicle detection unit 211 is sampled (step A3). Next, the accumulation flag is determined, and if the accumulation flag is set to “0” (step A5: YES), it is determined whether or not the vehicle presence / absence detection result has changed. That is, it is determined whether the value of the current sampled detection result data matches the value of the previous sampled detection result data. If they match, it is determined that they have not changed, and if they are different, it is determined that they have changed. .

  If it is determined that the vehicle presence / absence detection result has changed (step A7: YES), the operation state of the child device side controller 200 is shifted to the active state (step A9), and the power supply control unit 213 is moved to the child device side. The radio 300 is turned on (step A11). Further, the accumulation flag is set to “1” (step A13), and the sampled detection result data is accumulated as detection result accumulation data (step A15). Next, “1” is added to the accumulated bit number (step A17), and “1” is subtracted from the idle bit number (step A19). Then, the effective bit number is set to “1” (step A21).

  On the other hand, if the accumulation flag is set to “1” (step A5: NO), the sampled detection result data is accumulated as detection result accumulation data (step A23). Next, “1” is added to the accumulated bit number (step A25), and “1” is subtracted from the idle bit number (step A27). Further, it is determined whether or not the detection result of the presence / absence of the vehicle has changed, and if it has changed (step A29: YES), the effective bit number is updated to the current accumulated bit number (step A31).

  Thereafter, it is determined whether a broadcast notification has been received from the parent device 50, and if received (step A33: YES), vehicle detection data is generated (step A35). That is, vehicle detection data including the number of idle bits, the number of valid bits, and the detection result accumulation data at the time of receiving the broadcast notification is generated. Next, a transmission standby process is started (step A37).

  Further, the adjustment bit number Δn is updated based on the idle bit number and the effective bit number at the time of receiving the broadcast notification (step A39). Subsequently, data reset is performed (step A41). That is, the accumulated bit number is set to the initial value “0”, the idle bit number is set to “20−Δn”, and the effective bit number is set to “1”. Further, the detection result accumulation data is cleared and the accumulation flag is set to “0”.

  After that, for example, it is determined whether or not the transmission control process is to be terminated due to, for example, the power supply of the slave side controller 200 being cut off. If the transmission control process is terminated (step A43: YES), the loop A is exited. Exit.

  FIG. 14 is a flowchart for explaining a transmission standby process executed during the transmission control process. According to the figure, the transmission control unit 212 determines that the elapsed time from the reception time point of the broadcast notification is the total time of the predetermined transmission margin time Te and the transmission standby period Tw determined for the slave unit 10. When the total time has elapsed (step B1: YES), vehicle detection data is transmitted to the parent device 50 (step B3).

  And if transmission of this vehicle detection data is completed (step B5: YES), an accumulation flag will be judged. If the accumulation flag is set to “0” (step B7: YES), the power supply of the slave unit side radio device 300 is shut off (step B9), and the operation state of the own device is shifted from the active state to the sleep state. (Step B11). When the above process is performed, the transmission standby process is terminated.

  FIG. 15 is a flowchart for explaining the base unit side processing. According to the figure, first, it is determined whether or not a predetermined transmission interval (750 ms) has elapsed since the previous transmission of the broadcast notification, and if it has elapsed (step C1: YES), for all the slave units 10 Broadcast notification is broadcast (step C3)

  Moreover, if the vehicle detection data transmitted from the subunit | mobile_unit 10 are received (step C5: YES), the detection result of the presence or absence of the vehicle in the applicable period of the subunit | mobile_unit 10 will be decompress | restored based on this received vehicle detection data. . That is, as the detection result data in the corresponding cycle, first, the value of the immediately preceding restored bit is continued by the number of idle bits included in the received vehicle detection data (step C7). Next, the number of effective bits included in the vehicle detection data is expanded from the top of the detection result accumulated data (step C9). Then, if the restored detection result data is insufficient for the period (step C11: YES), for the missing bits, the value of the last developed bit is continued (step C13). If the above process is performed, it will return to step C1 and the same process will be repeated. The base unit processing is performed in this way.

[Action / Effect]
As described above, according to the present embodiment, in the vehicle detection system 1 including the child device 10 and the parent device 50 that are a plurality of vehicle detection devices, a predetermined period (750 ms) is sent from each child device 10 to the parent device 50. Vehicle detection data including a vehicle presence / absence detection result in the cycle is transmitted at intervals. In the subunit | mobile_unit 10, while the operation state of the subunit | mobile_unit side controller 200 is a sleep state normally, the power supply of the subunit | mobile_unit side radio | wireless machine 300 is interrupted | blocked.

  When the detection result of the presence / absence of the vehicle changes, the slave unit-side controller 200 shifts to the active state and the slave unit-side radio 300 is turned on, and the detection result data is accumulated from the detection result change point. Be started. Next, when a broadcast notification is received from the parent device 50, vehicle detection data including detection result accumulation data up to that point is transmitted to the parent device 50 via the child device side wireless device 300, and transmission is completed. After the power of the slave unit side wireless device 300 is cut off, the slave unit side controller 200 shifts to the sleep state. Thereby, suppression of the power consumption in the subunit | mobile_unit 10 is implement | achieved.

[Modification]
It should be noted that embodiments to which the present invention can be applied are not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit of the present invention.

(A) A plurality of vehicle detectors 100
For example, the case where the slave unit 10 includes a plurality of vehicle detectors 100 can be similarly applied. In this case, the slave side controller 200 receives, for example, detection signals from each of the plurality of vehicle detectors 100 installed for each lane, and detects the presence or absence of the vehicle for each of the detection signals from each vehicle detector. The

  FIG. 16 is a time chart showing an operation example of the slave unit 10 having a plurality of vehicle detectors 100. In the figure, a case where two vehicle sensors 30 are provided is shown. As shown in the figure, the slave-side controller 200 receives sensing signals from the two vehicle detectors 30 and generates vehicle presence / absence detection results 1 and 2 based on these sensing signals. .

  Then, when any one of the plurality of vehicle presence / absence detection results changes, the slave unit-side controller 200 changes the operation state of the slave unit-side controller 200 from the sleep state to the active state. The power of the side radio 300 is turned on. In addition, accumulation of detection result data is started for each vehicle sensor 30, and counting of the number of idle bits and the number of accumulated bits is started. When the broadcast notification is received, vehicle detection data including the number of idle bits, the number of effective bits, and the detection result accumulation data for each vehicle detector 30 at that time is generated and transmitted to the parent device 50. . That is, in the figure, the detection result 1 changes from “L” to “H” at the fifth bit (rise), and the detection result data is accumulated for both the detection results 1 and 2 from the fifth bit. Is started.

  FIG. 17 is a diagram illustrating a data configuration example of the vehicle detection data 20A in this case. As shown in the figure, the vehicle detection data 20A includes an idle bit number 21, valid bit number 22, and detection result accumulation data 23A. Data of each of the plurality of vehicle detectors 30 is stored in the detection result accumulation data 23A.

(B) Number of idle bits In the above-described embodiment, the initial value of the number of idle bits is “20−Δn”. However, the number of bits corresponding to one cycle may be “15”.

DESCRIPTION OF SYMBOLS 1 Vehicle detection system 10 Child machine 100 Vehicle detector 200 Child machine side controller 210 Processing part 211 Vehicle detection part, 212 Transmission control part, 213 Power supply control part 220 Storage part 221 Transmission control program 222 Vehicle detection data for transmission, 223 Count Data 300 Slave unit transmitter 50 Master unit 500 Master unit controller, 600 Master unit transmitter

Claims (7)

A vehicle detection device that inputs a detection signal from a vehicle detector and transmits vehicle detection data to a master unit via a wireless communication device,
Vehicle detection means for detecting the presence or absence of a vehicle based on the sensing signal;
A power-on means for turning on the power of the wireless communication device when a change occurs in the detection result by the vehicle detection means;
Accumulation means for accumulating data (hereinafter referred to as “detection result accumulation data”) from when the detection result by the vehicle detection means first changes within the period to the last change every predetermined cycle period; ,
Initial change waiting time counting means for counting the initial change waiting time until the detection result by the vehicle detecting means first changes from the start of the cycle period for each cycle period;
For each said cycle period, when a change in the detection result by the vehicle detection means within the period duration it did not occur without sending a given vehicle detection data relating to the period duration, when a change occurs After the power is turned on by the power-on means, the vehicle detection data including the detection result accumulation data related to the periodic period accumulated by the accumulating means and the initial change waiting time data related to the periodic period Transmission control means for performing control to transmit to,
A power shut-off means for shutting off the power of the wireless communication device after transmission of the vehicle detection data;
A vehicle detection apparatus comprising: The initial standby time counting means starts counting down from the time when the detection result by the vehicle detection means first changes in the cycle period, and uses the count value at the end of the cycle period as the initial change standby time. Is,
The vehicle detection device according to claim 1. When the sum of the time length of the detection result storage data related to the periodic period stored by the storage means and the initial change waiting time related to the periodic period exceeds the length of the periodic period, The adjustment means for subtracting the initial change waiting time for the period immediately after the adjustment time as the adjustment time,
The vehicle detection device according to claim 1, further comprising: The operation state of the own apparatus is shifted from the sleep state in which the operation of the vehicle detection unit is valid to the active state triggered by a change in the detection result by the vehicle detection unit, and the transmission control unit The vehicle detection device according to any one of claims 1 to 3, further comprising an operation state control unit that shifts to the sleep state after transmission of vehicle detection data. A vehicle detection device according to any one of claims 1 to 4 ;
A master unit that wirelessly communicates with each of the plurality of vehicle detection devices and receives the vehicle detection data from each vehicle detection device;
A vehicle detection system comprising: A vehicle detection system comprising a plurality of vehicle detection devices according to claims 1 to 4 and a master unit that wirelessly communicates with each of the plurality of vehicle detection devices and receives the vehicle detection data from each vehicle detection device. And
The base unit is
By maintaining the previous data value for the initial change waiting time included in the vehicle detection data, and then expanding the detection result accumulation data included in the vehicle detection data, the vehicle detection apparatus can be used in the cycle period. Means for deploying detected vehicle presence / absence from the vehicle detection data;
Vehicle detection system. A method for controlling a vehicle detection device, comprising vehicle detection means for inputting a detection signal from a vehicle sensor and detecting the presence or absence of a vehicle based on the detection signal, and transmitting vehicle detection data to a master unit via a wireless communication device Because
A power-on step of powering on the wireless communication device when a change occurs in the detection result by the vehicle detection means;
An accumulation step for accumulating detection result accumulation data from when the detection result by the vehicle detection means first changes within the period to the last change for each predetermined period;
An initial change waiting time counting step for counting an initial change waiting time until the detection result by the vehicle detecting means first changes from the start of the cycle period for each cycle period;
For each said cycle period, when a change in the detection result by the vehicle detection means within the period duration it did not occur without sending a given vehicle detection data relating to the period duration, when a change occurs After the power is turned on in the power-on step, control is performed to transmit the vehicle detection data including the detection result accumulation data related to the periodic period and the initial change waiting time data related to the periodic period to the master unit. A transmission control step;
A power shutdown step of shutting off the power of the wireless communication device after transmission of the vehicle detection data;
The control method of the vehicle detection apparatus containing

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