JP3208048B2 - Communication method of vehicle operation management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce power consumption required for the radio communication of a base station radio equipment by setting up the radio equipment to a power save mode when the necessity of communication is low, and when the necessity is increased, driving the radio equipment in a nomal power mode. SOLUTION: A receiving circuit 9 in a bus stop radio equipment 1 is driven only for relatively short time T2 and receives a radio wave through a receiving antenna 7 (normal operation mode). At the time of receiving a radio wave from an on-vehicle radio equipment, the circuit 9 is driven only for time T4 longer than the time T2 at a time interval T3 shorter than prescribed time T1 and receives the radio wave (continuous receiying mode). When the equipment 1 is in the normal operation mode, a transmitting circuit 13 stops transmission, and when the equipment 1 is turned to the continuous receiving mode, the circuit 13 is driven only for prescribed time T6 at prescribed time interval T5 and transmits a radio wave through a transmitting antenna 15. In this case, the radio wave receiving area of the equipment 1 is set up to a wide area and a radio wave transmitting area is set up narrower than the receiving area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a radio device provided at a base such as a bus stop or a subway station, and a radio device communicating with the base via a radio wave in a vehicle such as a bus or a subway.
The present invention relates to a vehicle operation management system that manages operation information of vehicles by performing two-way communication between the base and the vehicle.
The present invention relates to a communication method of a vehicle operation management system that can reduce power consumption required for wireless communication between a base and a vehicle.

[0002]

2. Description of the Related Art For example, transportation such as buses and subways has a social mission of transporting a large number of personnel safely and efficiently. However, for example, in the case of a bus, in order to travel on a general road mixed with a general vehicle,
Due to traffic congestion on the road and the like, it may not arrive at the bus stop at the time determined by the timetable. In this case, the people waiting for the bus at the bus stop would wait anxiously and wait for the bus when they would come, which was a great psychological stress, especially for those who were busy in time.

Therefore, recently, a radio device is provided at a base such as a bus stop or a subway station, and a radio device is provided in a vehicle such as a bus or subway to communicate with the base via radio waves, so that the base and the vehicle can communicate with each other. A vehicle operation management system that manages vehicle operation information by performing directional communication is gradually spreading. If this vehicle operation management system is applied to, for example, bus operation management, it is possible to effectively utilize the obtained operation information by managing operation information on which bus is running where. That is to say, for example, to people waiting for a bus at a bus stop, to give prediction information about how many minutes the bus will arrive at the bus stop,
The passengers of the bus can be informed of the prediction of how many minutes the bus will arrive at the next bus stop. Therefore, according to this bus operation management system, the psychological stress of those waiting for the bus can be removed, and the convenience of the bus user can be significantly improved.

[0004]

In the above-mentioned bus operation management system, a wireless device provided at a bus stop will be described. This bus stop wireless device has a transmitting antenna and a receiving antenna. The bus stop radio receives the radio wave transmitted from the on-vehicle radio provided in the vehicle via these antennas and transmits the radio wave to the on-vehicle radio. The transmitting and receiving antennas are required to transmit and receive radio waves reliably and efficiently with low power to and from the on-vehicle wireless device. Therefore, various technologies are applied to the transmitting and receiving antennas. ing. That is, for example, the receiving antenna is provided with directivity to limit the radio wave reception range to a narrow range, or the transmission antenna is installed above the bus operation route, and the radio wave is radiated from the transmission antenna toward the road surface. A technique such as transmitting a message has been applied.

[0005] However, according to the above-mentioned technology, although it is possible to reliably transmit and receive radio waves to and from a vehicle-mounted wireless device, in order to be able to immediately respond to a bus whose arrival is unknown, Since the bus stop radio was always kept in the operating state, radio waves were transmitted from the transmitting and receiving antennas, and the radio waves were waiting to be received, the power consumption required for this radio communication was considerable, and it was against the recent trend of energy saving. Had become. In addition, if a relatively inexpensive lithium battery having a high energy density can be used as a power source for the bus stop radio, for example, the cost required for the maintenance of the bus operation management system can be greatly reduced.
In the current system, it is difficult to adopt a lithium battery from the viewpoint of power consumption.Therefore, expensive solar cells and commercial power sources must be adopted. This has been an obstacle in disseminating the management system.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and reduces the power consumption required for wireless communication between a base and a vehicle, and also contributes to the spread of a vehicle operation management system. An object of the present invention is to provide a communication method of a system.

[0007]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, a plurality of bases are provided at appropriate intervals on a traveling route of a vehicle, and each of the bases is provided with a base. A vehicle operation that manages the operation information of the vehicle by providing the vehicle with an in-vehicle wireless device that communicates with the base wireless device via radio waves while performing a two-way communication between the base and the vehicle. In the management system, while setting a wide radio wave reception area in the base station radio, the radio wave transmission area is set narrower than the reception area,
If the base radio has not yet received radio waves from the on-board radio, the base radio is operated to receive radio waves at a predetermined low frequency and suspend transmission of radio waves, When the base transceiver receives radio waves from the on-board radio, the base transceiver receives radio waves at a frequency higher than the predetermined low frequency, and transmits radio waves between receptions of the radio waves. A communication method of a vehicle operation management system characterized by being operated.

According to the first aspect of the present invention, first, the radio wave reception area in the base station radio is set wide, while the radio wave transmission area is set narrower than the reception area. In the transmission / reception area set as described above, the two-way communication is performed between the base station radio and the on-board radio via radio waves. However, in this communication, if the base transceiver has not yet received the radio wave from the in-vehicle transceiver,
The base station radio is operated so as to receive radio waves at a predetermined low frequency and suspend transmission of radio waves. Here, the case where the base station radio has not yet received the radio wave from the in-vehicle radio means that the vehicle has not yet reached the radio wave reception area of the base station radio, and the distance between the base and the vehicle is large. Means that Therefore, when the distance between the base and the vehicle is large, the base transceiver is operated so as to receive radio waves at a predetermined low frequency and suspend transmission of radio waves. Then, when the base transceiver receives a radio wave from the onboard radio, the base transceiver receives the radio wave at a frequency higher than the predetermined low frequency, and transmits the radio wave between receptions of the radio wave. Activate. Here, the case where the base radio receives the radio wave from the on-board radio means that the vehicle has reached the radio wave reception area of the base radio and the distance between the base and the vehicle is short. . Therefore, when the distance between the base and the vehicle is approaching, the base transceiver is operated to receive radio waves at a frequency higher than the predetermined low frequency and transmit radio waves between receptions of the radio waves.

In other words, when the necessity of communication in the base radio is low, the base radio is operated in the power saving mode, and when the necessity of communication in the base radio increases,
It can be said that the base transceiver is operated in the normal power mode. Therefore, it is possible to reduce the average power consumption required for wireless communication in the base station radio.

The invention according to claim 2 is characterized in that when the base station radio does not receive radio waves for a predetermined time after receiving radio waves from the on-board radio,
The communication method of the vehicle operation management system according to claim 1, wherein the communication method is operated to receive radio waves at a predetermined low frequency and suspend transmission of the radio waves.

According to the second aspect of the present invention, if the base station radio does not receive radio waves continuously for a predetermined time after receiving radio waves from the on-board radio, the base station radio is set to a predetermined low frequency. To operate to receive radio waves and suspend transmission of radio waves. Here, the case where the base station radio does not receive the radio wave continuously for a predetermined time after receiving the radio wave from the in-vehicle radio, means that the vehicle once reaches the radio wave receiving area of the base radio, and Or the transmission of radio waves from the in-vehicle wireless device has been suspended for a predetermined time within the reception area. In such a case, it is determined that the necessity of communication has been reduced in the base radio, and the base radio is shifted from the normal power mode to the power saving mode. Therefore, it is possible to reduce the average power consumption required for wireless communication in the base station radio.

Further, according to a third aspect of the present invention, a plurality of bases are provided at appropriate intervals on a traveling route of a vehicle, and a base station radio is provided for each of the bases. A vehicle operation management system that manages vehicle operation information by providing an in-vehicle wireless device that communicates with the machine via radio waves and performing bidirectional communication between the base and the vehicle,
In the in-vehicle wireless device, the location of each of the plurality of bases on the travel route of the vehicle and route information on the distance between the bases are stored in advance, and when the vehicle travels along the travel route, the vehicle The travel speed, and captures the operation information about the integrated travel distance at appropriate intervals, based on the operation information and the route information, predicts the remaining distance between the base and the vehicle, the remaining distance and a predetermined value And when the remaining distance is equal to or less than a predetermined value, the vehicle-mounted wireless device is operated to alternately receive and transmit radio waves at a predetermined frequency. It is.

According to the third aspect of the present invention, first, the in-vehicle wireless device stores in advance the route information regarding the arrangement of each of the plurality of bases on the traveling route of the vehicle and the distance between the bases. Next, when the vehicle travels along the traveling route, operation information on the traveling speed of the vehicle and the accumulated traveling distance is taken in at appropriate intervals. Then, based on the operation information and the route information, the remaining distance between the base and the vehicle is predicted, and the remaining distance is compared with a predetermined value. , So as to alternately receive and transmit radio waves at a predetermined frequency. In other words, when it is determined from the remaining distance between the base and the vehicle that the vehicle is not approaching the base, it is determined that the vehicle has approached the base while maintaining the sleep mode in which the reception and transmission operations of the in-vehicle wireless device are suspended. Then, the in-vehicle wireless device is operated in a normal power mode in which radio waves are alternately received and transmitted at a predetermined frequency.

Therefore, the vehicle-mounted wireless device shifts the vehicle-mounted wireless device from the sleep mode to the normal power mode when the vehicle approaches the base and the necessity of communication arises. Average power consumption required for the operation can be reduced.

According to a fourth aspect of the present invention, when the on-vehicle radio receives a radio wave from the base radio, the on-vehicle radio is
4. The communication method for a vehicle operation management system according to claim 3, wherein the communication is performed so as to suspend reception and transmission of radio waves continuously for a predetermined time.

According to the fourth aspect of the present invention, when the on-vehicle wireless device receives the radio wave from the base station radio device, the on-vehicle radio device is operated so as to stop receiving and transmitting the radio wave continuously for a predetermined time. Here, the fact that the in-vehicle wireless device receives a radio wave from the base radio device means that the vehicle has reached the radio wave transmission area of the base radio device. In such a case, it is determined that the necessity of communication in the vehicle-mounted wireless device has become low, and the vehicle-mounted wireless device is shifted from the normal power mode to the sleep mode. Therefore, it is possible to reduce the average power consumption required for wireless communication in the vehicle-mounted wireless device.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A communication method of a vehicle operation management system according to the present invention will be described below in detail by exemplifying an embodiment in which the present system is applied to bus operation management.

FIG. 1 is a block diagram showing a base station radio of the vehicle operation management system according to the present invention, FIG. 2 is a block diagram showing a vehicle-mounted radio of the vehicle operation management system according to the present invention, and FIG. , The external configuration diagram of the base transceiver, FIG.
FIG. 5 is a conceptual diagram showing an embodiment of a vehicle operation management system according to the present invention, FIG. 5 is an operation flowchart of the vehicle operation management system according to the present invention, and FIGS. 6 and 7 are operations of the vehicle operation management system according to the present invention. Timing chart, FIG.
9 are diagrams for explaining the operation of the vehicle operation management system according to the present invention. In the present embodiment, members having the same functions are given the same names, and overlapping descriptions thereof are partially omitted.

First, a schematic configuration of the vehicle operation management system according to the present invention will be described with reference to FIG. 4. In the road RD, a predetermined route of the bus CR is provided at an appropriate interval. A plurality of bus stops BS are installed. The bus stop BS is provided with a bus stop radio 1 as a base radio, while the bus CR is provided with an on-board radio 3. The bus operation management system manages operation information of the bus CR by performing two-way wireless communication between the bus stop radio device 1 and the on-vehicle radio device 3 via radio waves. Specifically, the bus operation management system is a bus C
By sharing the operation information of R between the bus stop BS and the bus CR, for example, people waiting for the bus at the bus stop BS are notified of prediction information that the bus CR will soon arrive at the bus stop BS. Further, it is possible to notify the passengers of the bus CR of prediction information such as that the bus CR will soon arrive at the next bus stop BS. For those who wait for the bus at the bus stop BS, the bus CR will stop the bus stop B in minutes.
It is also possible to notify the prediction information about whether to arrive at S, or to notify the passengers of the bus CR about the prediction of how many minutes the bus CR will arrive at the next bus stop BS. Further, if the operation information of the bus CR is taken from each bus stop BS to the operation management center via a public telephone line or the like, the operation management center can determine which bus CR runs on which route and which route. It is also possible to know whether or not.

Next, the configuration of each part of the bus operation management system having the above-described functions will be described. First, the appearance of the bus stop radio 1 provided at the bus stop BS will be described. As shown in FIG. 3, the bus stop radio 1 is connected to the reception antenna 7 and the transmission antenna 7 on both opposing side surfaces of the box-shaped housing 53. The antenna 15 is provided, and a mounting plate 55 used when mounting the wireless device 1 to the bus stop BS is provided on the bottom surface of the housing 53.

Further, the internal configuration of the bus stop radio 1 will be described. As shown in FIG. 1, the bus stop radio 1 has a reception circuit 9 to which a reception antenna 7 is connected, and a transmission circuit to which a transmission antenna 15 is connected. 13 and a control circuit 11 to which the receiving circuit 9 and the transmitting circuit 13 are connected.

As shown in FIG. 6, the receiving circuit 9 operates only for a second predetermined time T2 which is a relatively short time with an interval of the first predetermined time T1. To receive radio waves. The operation mode of the bus stop radio 1 at this time is called a normal operation mode. On the other hand, once the receiving circuit 9 has successfully received the radio wave from the on-vehicle wireless device 3, a time longer than the second predetermined time T2 is provided after an interval of the third predetermined time T3, which is shorter than the first predetermined time T1. It operates only for the fourth predetermined time T4, and receives radio waves via the receiving antenna 7 during this operation. The operation mode of the bus stop radio 1 at this time is called a continuous reception mode. Note that the sensitivity of the receiver constituted by the receiving antenna 7 and the receiving circuit 9 is, as shown in FIG. 9, the reception radio wave which is the upper limit of the distance that the bus stop radio 1 can receive the transmission radio wave from the onboard radio 3. The sensitivity is set so that the reaching distance D2 is 100 m or more. That is, the reception area of the bus stop radio 1 is set to at least 100 m or more. Thereby, the bus stop radio 1 can detect the arrival of the bus CR as soon as possible.

The transmission circuit 13 suspends transmission when the bus stop radio 1 is in the normal operation mode, and operates for the sixth predetermined time T6 at the interval of the fifth predetermined time T5 when shifting to the continuous reception mode. At the time of this operation, a predetermined radio wave is transmitted via the transmission antenna 15. The performance of the transmitter constituted by the transmission antenna 15 and the transmission circuit 13 is, as shown in FIG. 9, the transmission radio wave which is the upper limit of the distance that the in-vehicle radio 3 can receive the transmission radio from the bus stop radio 1. The sensitivity is set so that the reaching distance D1 is within 20 m.
That is, the transmission area of the bus stop radio 1 is at most 20
m. This allows the bus stop radio 1 to pinpoint the position of the bus CR with high accuracy.

The control circuit 11 includes a clock circuit 17.
A memory 19 comprising a ROM for storing programs and a RAM for storing data; a voltage drop detection circuit 25 for detecting a voltage between terminals of a battery 21 such as a lithium battery via a power supply circuit 23; And an RS-232C circuit 27 to which a connector 29 is connected. If the control circuit 11 is connected to a central management device of an operation management center or the like via the connector 29, an appropriate modem, a public telephone line, or the like, the operation information of the bus can be centrally managed in the management center.

The control circuit 11 executes a program stored in the memory 19 and controls various processes. For example, when the bus stop radio 1 is in the normal operation mode, the control circuit 11 instructs the reception circuit 9 to perform a reception operation at a predetermined low frequency, while stopping the transmission to the transmission circuit 13. Command. Further, the control circuit 11 sets the bus stop radio 1 in the continuous reception mode,
While instructing the receiving circuit 9 to perform a receiving operation at a predetermined high frequency, the transmitting circuit 13 is instructed to perform a transmitting operation at a predetermined timing. Further, the control circuit 11 has a clock function for displaying the time on a liquid crystal panel (not shown) provided at the bus stop BS, and an ID transmission function for transmitting its own bus stop identification code preset for each bus stop BS name to the transmission circuit 13. When the voltage drop detection circuit 25 detects that the voltage between the terminals of the battery 21 has dropped to a predetermined value or less, the liquid crystal panel or the like is provided with a function of displaying that the battery is dead. Note that the bus stop identification code is included in a predetermined radio wave transmitted via the transmission antenna 15 when the transmission circuit 13 operates, and the in-vehicle wireless device 3 that has received the bus stop identification code transmits the approaching bus stop BS. Can be recognized.

Next, the internal configuration of the vehicle-mounted radio 3 for performing radio communication with the bus stop radio 1 will be described. As shown in FIG. 2, the in-vehicle wireless device 3 includes a receiving circuit 33 and a transmitting circuit 35 to which the transmitting / receiving antenna 31 is connected, respectively, and a control circuit 37 to which the transmitting / receiving circuits 33 and 35 are connected. The control circuit 37 includes a memory 39, a power supply circuit 43 for supplying power from a power supply 41 such as a battery to each unit of the control circuit 37 and the like, and a connector 47.
Are connected to an RS-232C circuit 45. The memory 39 stores information on the travel route of the bus CR, that is, information on in which order the bus CR arrives at the final point bus stop BS from which bus stop BS and from which bus stop BS. Route information on the distance between the bus stops and the identification code of the bus stop BS that has passed last is stored. This route information is used for a bus stop prediction described later, which is executed by the control circuit 37.

The on-vehicle wireless device 3 configured as described above includes:
The vehicle information monitoring device 5 is connected via the RS-232C cable 48 and the connector 49. The vehicle information monitoring device 5 is configured by connecting a connector 49 to a vehicle operation recording device 51. The vehicle operation recording device 51 has input therein operation information such as an integrated traveling distance of the bus CR starting from a certain bus stop BS, a current traveling speed, and a current time. Is supplied to the control circuit 37 of the machine 3. In response to this, the control circuit 37 executes a bus stop prediction process. That is, the control circuit 37
The route information of the bus CR is read from the memory 39, the remaining distance from the current position to the next bus stop BS is calculated based on the route information and the operation information, and the next distance is calculated from the remaining distance and the current speed of the bus CR. The remaining time required to arrive at the bus stop BS is calculated. This remaining time is used when determining the transmission / reception timing of radio waves in the receiving circuit 33 and the transmitting circuit 35 described in detail later. The role of the bus stop prediction function described above is as follows. First, by avoiding the transmission of unnecessary radio waves by the bus CR as much as possible, other systems using frequencies close to the communication radio waves are adversely affected. To prevent power consumption and to eliminate unnecessary radio wave transmission to save power.
Depending on conditions such as the environment of the installation location of the vehicle, the reception radio wave reach distance D2 may be considerably long, and if the radio wave is transmitted from the on-board radio 3 early without predicting the bus stop, the radio in the bus stop radio 3 The communication operation timing is also advanced, and as a result, extra power is consumed by the advance of the communication operation timing and the life of the battery 21 of the bus stop radio 3 is shortened. Fourth, to determine the code, the role of securing a large number of communications between the bus stop BS and the bus CR even when the communication state with the bus stop radio 3 is poor, and avoiding the result that the bus stop BS could not be found, etc. Have. The control circuit 37
In addition to the bus stop prediction function described above, an error detection function for detecting a communication error with the bus stop radio 1 and a time when the bus CR passes or arrives at the bus stop BS are stored in the memory 39.
Further, a bus stop passing time recording function and the like to be stored in the memory are further provided.

Next, the operation of the bus stop radio 1 and the on-vehicle radio 3 in the above-mentioned bus operation management system will be described with reference to FIGS.

First, on the bus CR side, the on-board radio 3
The control circuit 37 reads the route information of the bus CR from the memory 39, calculates the remaining distance from the current position to the next bus stop BS based on the route information and the operation information, and also calculates the remaining distance and the bus CR. From the current speed, the remaining time required to arrive at the next bus stop BS is calculated. With reference to the calculated remaining distance, the control circuit 37 determines whether or not the distance between the bus CR and the next bus stop BS is equal to or less than a predetermined distance DS. This determination is repeated until the distance between the bus CR and the next bus stop BS becomes less than or equal to a predetermined distance DS. When it is determined that the distance between the bus CR and the next bus stop BS has become equal to or less than the predetermined distance DS, the control circuit 37 executes a predetermined process based on the program stored in the memory 39. . That is, the control circuit 37 first activates the receiving circuit 33, and executes so-called carrier sensing for checking whether or not the in-vehicle wireless device 3 is receiving a radio wave (step 1, hereinafter referred to as S1).
Note that this carrier sense is executed in an attempt to prevent a communication error from occurring before the transmission timings of the other party and this party overlap. If it is determined by the carrier sense that the in-vehicle wireless device 3 is not receiving a radio wave, the control circuit 37 starts up the transmission circuit 35, executes a command to transmit a radio wave at a predetermined timing, and executes a bus stop. The wireless device 1 is called (S3). On the other hand, when it is determined by the carrier sense that the in-vehicle wireless device 3 is receiving the radio wave, the control circuit 37 continues the carrier sense and transmits the signal until it is determined that the in-vehicle wireless device 3 is not receiving the radio wave. The circuit 35 is not started.

Here, the processing of steps S1 and S3 will be described with reference to FIGS. Prior to this description, as shown in FIG. 8, the bus CR is currently located at the point A and is traveling at 40 km / h, the distance between the point A and the bus stop BS is 200 m, and this distance 200 m It is assumed that this corresponds to the predetermined distance DS. Further, assuming that the reception radio wave arrival distance D2 is set to 100 m, the position at which the bus CR reaches the reception area of the bus stop radio 1 is set to point B, while the transmission radio wave arrival distance D1 is set to 10 m. It is assumed that the bus CR reaches the transmission area of the bus stop radio 1 as a point C.

At point A, the control circuit 37 of the on-vehicle radio 3
Calculates the remaining distance from the current position to the next bus stop BS as described above, and calculates the remaining distance and the bus C
From the current speed of R, the remaining time required to arrive at the next bus stop BS is calculated. The remaining distance calculated at this time is 2
00m, and the remaining time is 18 seconds. Further, the control circuit 37 determines whether or not the calculated remaining distance is equal to or less than a predetermined distance DS. As described above, since the remaining distance 200 m is equal to the predetermined distance DS as described above, it is determined that the remaining distance is equal to or less than the predetermined distance DS. Then, the control circuit 37 starts up the reception circuit 33, and
, And calculates a predicted time at which the bus CR will reach the point B. The result of this calculation is that the distance 100m from point A to point B is 40
Since the vehicle travels at km / h, the time to reach point B is calculated to be 9 seconds later. The estimated arrival time at point B is determined by the bus CR
Therefore, the calculation of the predicted time is repeated, and the amount of change in the predicted arrival time is appropriately compensated by, for example, increasing or decreasing in seconds. When it is determined by the carrier sense that the in-vehicle wireless device 3 is not receiving a radio wave, the control circuit 37 starts up the transmission circuit 35 at a point B shown in FIGS. Is executed, and the bus stop radio 1 is called. In this call, the control circuit 37 reads the bus stop identification code of the next bus stop BS from the memory 39 and causes the transmission circuit 35 to transmit a radio wave including the identification code.

In response to the call from the on-vehicle radio 3, the control circuit 11 of the bus stop radio 1 continues the operation of the receiving circuit 9 so that its operation mode becomes the reception timing in the normal operation mode (S9). The receiving circuit 9 determines whether an incoming radio wave has been received (S11). Here, the operation in the normal operation mode will be described. As shown in FIG. 6, the receiving circuit 9 operates for a relatively short second predetermined time T2 with an interval of the first predetermined time T1. Then, during this operation, radio waves are received via the receiving antenna 7. On the other hand, in the normal operation mode, the transmission circuit 13
Has stopped transmitting radio waves. In this way, by restricting the operations of the reception circuit 9 and the transmission circuit 13 to the necessary minimum in the normal operation mode, the power consumption required for wireless communication in the bus stop radio 1 is minimized.

As a result of the incoming call determination in step S11,
If it is determined that no incoming radio wave has been received, the control circuit 1
1 continues the operation of the receiving circuit 9 in the normal operation mode, and when it is determined that the radio wave has been received, determines whether the operation mode of the bus stop radio 1 is the continuous reception mode (S13). . When it is determined that the operation mode is not the continuous reception mode as a result of the mode determination, a process of setting the operation mode to the continuous reception mode is performed (S1).
5). Here, the operation in the continuous reception mode will be described. As shown in FIG. 6, once the reception circuit 9 has successfully received the radio wave from the on-vehicle wireless device 3, the reception circuit 9 has a time shorter than the first predetermined time T1. After an interval of three predetermined times T3, it operates for a fourth predetermined time T4, which is longer than the second predetermined time T2, and receives radio waves via the receiving antenna 7 during this operation. On the other hand, in the continuous reception mode, the transmission circuit 13 operates for the sixth predetermined time T6 at an interval of the fifth predetermined time T5.
A predetermined radio wave is transmitted through. In addition, the in-vehicle wireless device 3
That the bus CR has stopped at the bus stop B
S means that the receiving circuit 9 and the transmitting circuit 13 are at appropriate timing in such a case.
Is operated, the communication with the in-vehicle wireless device 3 is ensured.

If the operation mode is determined to be the continuous reception mode as a result of the mode determination in step S13, the control circuit 11 causes the reception circuit 9 to perform carrier sense (S17). While observing the transmission / reception timing of the radio wave in the on-vehicle wireless device 3, the transmitting circuit 13 is operated in accordance with the timing that the on-vehicle wireless device 3 may be receiving, and the radio wave is transmitted to respond to the on-vehicle wireless device 3. (S19). That is, in the continuous reception mode, the control circuit 11 activates the transmission circuit 13 every time a radio wave is received from the on-vehicle wireless device 3, transmits a radio wave, and responds to the on-vehicle wireless device 3. As a result of this response, when the in-vehicle wireless device 3 succeeds in reception, the control circuit 11 continuously operates the receiving circuit 9 for a predetermined time, for example, 10 seconds, to monitor the transmission of the in-vehicle wireless device 3, and within this monitoring time, If there is no reception, the operation mode of the bus stop radio 1 is returned to the normal operation mode (S21).

Returning to the control of the bus CR again, after the bus stop calling process in step S3, the control circuit 37 of the on-vehicle wireless device 3 operates the receiving circuit 33 to receive at a predetermined timing as shown in FIG. When the radio wave from the bus stop radio device 1 is successfully received, transmission and reception of the radio wave are suspended for a predetermined period. More specifically, step S3
After the bus stop calling process, the control circuit 37 of the on-vehicle radio 3
Operates the receiving circuit 33 to perform reception at a predetermined timing, and in this reception, determines whether an incoming radio wave from the bus stop radio 1 has been received (S5). As a result of the incoming call determination, when it is determined that the incoming radio wave from the bus stop radio 1 has not been received, the control circuit 37 returns the processing to step S1 and repeats the processing after the carrier sense again. Note that in the processing of steps S1 to S5,
If the transmission / reception timing is determined based on only the travel distance of the bus CR when the bus CR approaches the bus stop BS, the communication time between the bus CR and the bus stop BS may be insufficient due to an accumulated error of the travel distance. For the bus CR
It is desirable to determine the transmission / reception timing while referring to both the traveling distance and the traveling speed of the vehicle.

On the other hand, as a result of the incoming call determination in step S5, if it is determined that an incoming radio wave has been received from the bus stop radio 1, the control circuit 37 determines that the bus CR has arrived at the bus stop BS at this time. The time at this time is read from the vehicle operation recording device 51, and this arrival time is stored in a predetermined address of the memory 39 in association with the identification code of the arriving bus stop BS. At this time, the control circuit 37 further controls the reception circuit 33 and the transmission circuit 35 for a predetermined time, for example, 10 seconds.
Is stopped (S7). When the predetermined pause time ends, the control circuit 37 returns the operation mode of the in-vehicle wireless device 3 to the normal operation mode, and waits for the next bus stop BS to approach. Note that the operation of the reception circuit 33 and the transmission circuit 35 can be stopped until the bus stop BS approaches to some extent by the bus stop prediction, following the stop time of step S7.

In the bus operation management system operating as described above, the power consumption of the bus stop radio 1 will be described. First, as a calculation condition, the current consumption during reception is set to 4 mA.
It is assumed that the operation current at rest is 20 μA, the current consumption at transmission is 30 mA, the continuous reception mode occurs at a frequency of 100 times / month, and this continuous reception mode lasts for one minute each time. 3.6V / capacity 8000
When a mAh lithium battery is used, the bus stop radio 1
Has an average current consumption of 560 μA. Assuming that the capacity of the lithium battery can be used up to 70% with this average current consumption, the battery life is about one year. Therefore, the above-described lithium battery is used as the battery of the bus stop radio 1 of the bus operation management system. It turns out that it is possible.

In the embodiment of the present invention, an appropriate frequency band can be selected and used as the frequency band of the radio wave used by the bus stop radio 1 and the on-vehicle radio 3. Further, the frequency of the radio wave used by the bus stop radio 1 and the on-vehicle radio 3 can be configured to be appropriately changeable even during communication. In this way, for example, even if there is a radio device using a radio wave frequency similar to that of the bus stop radio device 1 near the bus stop BS, the radio wave frequency can be changed appropriately during the communication. In addition, it is possible to reliably avoid interference by the wireless device or the like.

In the embodiment of the present invention, a bus is exemplified as a vehicle and a bus stop is exemplified as a base. However, the present invention is not limited to this. For example, a subway, a snowplow, It is needless to say that the present invention can be implemented by providing an in-vehicle wireless device in a watering vehicle, a garbage cleaning vehicle, or the like, and setting a base station wireless device in a subway station as a base, a wireless station appropriately provided on a traveling route of the vehicle, or the like. .

[0040]

According to the first aspect of the present invention, when the necessity of communication in the base station is low, the base station is operated in the power saving mode, and the necessity of communication in the base station becomes high. By operating the base transceiver in the normal power mode, the average power consumption required for wireless communication in the base transceiver can be reduced.

According to the second aspect of the present invention, after the vehicle has once arrived at the radio wave receiving area of the base station radio, it has gone out of the receiving area, or when the vehicle has been in the receiving area, the vehicle has a radio wave. If the transmission of the radio wave has been suspended for a predetermined period of time, it is determined that the necessity of communication has decreased in the base radio, and the base radio is shifted from the normal power mode to the power saving mode. Let me. Therefore, it is possible to reduce the average power consumption required for wireless communication in the base station radio.

Further, according to the third aspect of the present invention, the vehicle-mounted wireless device shifts the vehicle-mounted wireless device from the sleep mode to the normal power mode when the vehicle approaches the base and communication becomes necessary. Therefore, the average power consumption required for wireless communication in the on-vehicle wireless device can be reduced.

According to the fourth aspect of the invention, when the vehicle reaches the radio wave transmission area of the base station radio, it is determined that the necessity of communication in the on-vehicle radio has been reduced, and the on-board radio has been determined. The machine is transitioning from normal power mode to hibernate mode. Therefore, it is possible to reduce the average power consumption required for wireless communication in the vehicle-mounted wireless device.

As described above, claims 1 to 4
According to the invention, the average power consumption required for the wireless communication between the base and the vehicle in the vehicle operation management system can be reduced, and the reduction in the power consumption can significantly reduce the maintenance and management cost of the system, and as a result, It has an extremely excellent effect of contributing to the spread of operation management systems.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a base transceiver of a vehicle operation management system according to the present invention.

FIG. 2 is a block diagram showing an in-vehicle wireless device of the vehicle operation management system according to the present invention.

FIG. 3 is an external configuration diagram of a base station radio.

FIG. 4 is a conceptual diagram showing an embodiment of a vehicle operation management system according to the present invention.

FIG. 5 is an operation flowchart of the vehicle operation management system according to the present invention.

FIG. 6 is an operation timing chart of the vehicle operation management system according to the present invention.

FIG. 7 is an operation timing chart of the vehicle operation management system according to the present invention.

FIG. 8 is a diagram for explaining the operation of the vehicle operation management system according to the present invention.

FIG. 9 is a diagram for explaining the operation of the vehicle operation management system according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 bus stop radio (base radio) 3 in-vehicle radio 5 vehicle information monitoring device 7 reception antenna 9 reception circuit 11 control circuit 13 transmission circuit 15 transmission antenna 17 clock circuit 19 memory 21 battery 23 power supply circuit 25 voltage drop detection circuit 27 RS -232C circuit 28 Flat cable 29 Connector 31 Transmitting and receiving antenna 31 33 Receiving circuit 35 Transmitting circuit 37 Control circuit 39 Memory 41 Power supply 43 Power supply circuit 45 RS-232C circuit 47 Connector 48 RS-232C cable 49 Connector 51 Vehicle operation recording device 53 Housing 55 Mounting plate BS bus stop CR bus RD Road

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Jang Jiang 1500 Onjuku, Susono City, Shizuoka Prefecture Yazaki Sogyo Co., Ltd. In-house (56) References JP-A-61-141100 (JP, A) JP-A-5-174295 (JP, A) JP-A-59-148438 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G08G 1/127 H04B 7/26

Claims (4)

(57) [Claims] 1. A plurality of bases are provided at appropriate intervals on a traveling route of a vehicle, and a base transceiver is provided at each of the bases. A vehicle operation management system that manages operation information of a vehicle by providing a vehicle-mounted wireless device for communication and performing bidirectional communication between a base and a vehicle, wherein a radio wave reception area in the base wireless device is set to be wide. The radio wave transmission area is set to be narrower than the reception area, and if the base radio has not yet received radio waves from the on-board radio, the base radio is set to a predetermined low level. Receives radio waves at a frequency and operates to suspend transmission of radio waves, when the base station radio receives radio waves from the on-board radio, the base station radio is higher than the predetermined low frequency. Receive radio waves at a frequency A communication method for a vehicle operation management system, wherein the communication method is operated to transmit a radio wave between receptions of two radio waves. 2. If the base station radio does not receive radio waves continuously for a predetermined time after receiving radio waves from the on-board radio, the base station radio receives radio waves at a predetermined low frequency. The communication method for a vehicle operation management system according to claim 1, wherein the communication is operated so as to suspend transmission of radio waves. 3. A plurality of bases are provided at appropriate intervals on a traveling route of a vehicle, and a base transceiver is provided at each of the bases. A vehicle operation management system that manages operation information of a vehicle by providing an on-vehicle wireless device for communication and performing bidirectional communication between a base and a vehicle, wherein the on-vehicle wireless device includes: The location information of each base and the route information about the distance between the bases are stored in advance, and when the vehicle travels along the travel route, the travel speed of the vehicle and the operation information about the accumulated travel distance are appropriately changed. Taking in at intervals, predicting a remaining distance between the base and the vehicle based on the operation information and the route information, comparing the remaining distance with a predetermined value, and when the remaining distance becomes equal to or less than a predetermined value, Said The placing radio receives radio waves alternating at a predetermined frequency, and a communication method for a vehicle operation management system, characterized in that to operate to transmit. 4. When the on-vehicle wireless device receives a radio wave from the base radio device, the on-vehicle radio device is operated so as to stop receiving and transmitting the radio wave continuously for a predetermined time. Item 4. A communication method for a vehicle operation management system according to item 3.