JP3589896B2 - Mobile data communication system and mobile mounted communication device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a data communication system in a mobile object, and more particularly, to a mobile data communication system in which deterioration of communication quality due to shadowing that may occur due to a positional relationship between mobile objects is prevented as much as possible.
The present invention also relates to a mobile communication device that communicates with the mobile communication system as described above.
[0002]
[Prior art]
Although a data communication system for a mobile body such as a car is performed between a base station and a vehicle, a shadowing state occurs in which communication with the base station becomes impossible due to a barrier of another vehicle. In such a data communication system, since the communication state depends on the relative positional relationship between the vehicle and another vehicle, the probability of occurrence of the shadowing state is much higher than in other wireless communication systems. In addition, it cannot be specified to some extent in a place like other wireless communication systems, and it is difficult to take measures to prevent shadowing.
[0003]
FIG. 1 is a diagram illustrating an example of a conventional mobile communication system.
The control station 10 controls the base stations 20-1, 20-2, 20-3,. The base station 20-1 has control of the vehicles A and B in the area of the base station 20-1 under the control of the supervising station 10. The base station 20-1 periodically communicates with the vehicle A and the vehicle B to acquire position information. Further, the base station 20-1 transmits information to the vehicles A and B as necessary.
[0004]
Now, it is assumed that the vehicle A and the vehicle B are traveling near each other in the same direction. A communication path from the base station 20-1 to the vehicle A and the vehicle B is indicated by a broken line in FIG. If the vehicle A is a wagon-type vehicle and the vehicle B is a standard passenger car, and the vehicle A has a width and a height higher than the vehicle B, the radio wave from the base station 20-1 to the vehicle B is In some cases, a shadowing state in which the vehicle A does not reach the vehicle B due to an obstacle may occur.
[0005]
In this case, in the prior art, if data communication is interrupted due to shadowing, a data retransmission method for controlling data communication at the time of shadowing by performing data retransmission a certain number of times, and performing shadowing on the mobile side (vehicle). A method for predicting and transmitting data to be transmitted from the mobile side after the shadowing is eliminated, and controlling the mobile side to restart the data communication by transmitting the data (Japanese Patent Laid-Open No. 7-154856). The data communication at the time of the occurrence of shadowing is realized by a method of controlling data communication by controlling data communication and avoiding shadowing by changing a communication path (JP-A-9-247063).
[0006]
[Problems to be solved by the invention]
However, in the conventional mobile communication system, no consideration has been given to shadowing caused by the positional relationship between the mobile objects.
Therefore, a first object of the present invention is to provide a mobile data communication system that prevents as much as possible communication quality deterioration due to shadowing that may occur due to the positional relationship between mobile objects.
[0007]
A second object of the present invention is to provide a mobile communication device that communicates with the mobile communication system as described above.
[0008]
[Means for Solving the Problems]
In order to solve the first problem of the present invention, the present invention provides a mobile data communication system for communicating with a communication device mounted on a mobile present in a communication area, as described in claim 1. A mobile object information obtaining means for obtaining information on the size of a mobile object existing in the communication area, a position estimating means for estimating a position of the mobile object existing in the communication area, a size and a predicted position of each mobile object And a communication control means for controlling data communication with respect to the moving object based on a result of the prediction by the shadowing estimating means. Is configured.
[0009]
In such a system, by predicting the position of each mobile unit, it is possible to predict mobile units that run near each other. In addition, the occurrence of shadowing can be predicted in advance based on information on the sizes of the moving objects traveling near each other. Further, by predicting shadowing in advance, it is possible to control data communication to a mobile object in which shadowing is predicted to occur.
[0010]
The moving body information includes information such as the moving body ID, the type of the moving body, and the size of the moving body.
The position predicting unit predicts the position of the moving body based on information such as the current position, the destination, and the traveling speed of the moving body.
From the viewpoint of predicting the occurrence of shadowing in advance based on information on the size of a moving object, the present invention provides a mobile data communication system according to claim 1 as described in claim 2. The moving body information acquiring means is configured to have a means for acquiring information on the size of each moving body from a database registered in advance.
[0011]
Further, from the viewpoint of predicting the position of the mobile unit, the present invention provides the mobile data communication system according to the first aspect, wherein the position prediction unit is mounted on each mobile unit. And a predicted position calculating means for calculating a predicted position of each mobile unit based on information indicating a moving state of the mobile unit transmitted from the communication device.
[0012]
From the viewpoint of avoiding the occurrence of shadowing, the present invention provides a mobile data communication system according to any one of claims 1 to 3, wherein the communication control means includes: When the prediction result that the occurrence of shadowing is predicted by the means is obtained, the height of the antenna of the communication device mounted on the mobile object is set with respect to the moving object predicted to generate the shadowing. Is configured to include an antenna adjustment instruction unit that transmits control data for adjusting the frequency.
[0013]
In such a system, a moving object predicted to generate shadowing can avoid shadowing by adjusting the antenna in advance based on the received control data.
Further, from the viewpoint of determining whether shadowing can be avoided by adjusting the antenna, the present invention provides the mobile data communication system according to claim 4, wherein the antenna adjustment instructing means is provided. Is based on the predicted position of a moving object affected by shadowing in an area where shadowing is predicted to occur and information on the predicted position and size of the moving object affected by shadowing. Having avoidance determination means for determining whether or not the shadowing can be avoided by adjusting the height of the antenna of the communication device of the moving object to receive the information, when the avoidance determination means determines that the shadowing can be avoided. , For transmitting control data for adjusting the height of the antenna.
[0014]
In such a system, if shadowing can be prevented by raising the antenna of the mobile, the mobile receives control data indicating the height of the antenna before shadowing occurs. The loss of communication data due to ing can be prevented.
In addition, from the viewpoint that, when shadowing cannot be prevented, the mobile side can recognize a time zone during which data communication is interrupted, the present invention provides the mobile data according to claim 5 as described in claim 6. In the communication system, the communication control means may further include, when the avoidance determination means determines that the shadowing cannot be avoided, data indicating that communication will be interrupted in a shadowing occurrence predicted time zone. Is configured to have data transmission means for transmitting to a mobile body in which the occurrence of is expected.
[0015]
In such a system, when shadowing cannot be avoided by adjusting the antenna, the mobile unit can recognize in advance that communication will be interrupted in the shadowing occurrence prediction time zone.
Further, from the viewpoint of preventing data loss in a predicted time zone of occurrence of shadowing, the present invention provides a mobile data communication system according to claim 5, wherein: Further, when the avoidance determination means determines that the shadowing can not be avoided, data holding control means for storing the data to be delivered to the moving body in a storage unit during the shadowing occurrence predicted time zone, Data distribution control means for distributing the data stored in the storage unit to the mobile body after the elapse of the predicted time period.
[0016]
In such a system, data to be delivered to the mobile during the shadowing occurrence predicted time period is stored in the storage unit, and after the predicted time period, the data stored in the storage unit is delivered to the mobile body. You. Therefore, the mobile can reliably receive the data.
Further, in order to solve the second problem of the present invention, the present invention predicts the occurrence of shadowing based on the predicted position of each moving object existing in the communication area, as described in claim 8. A mobile data communication system that communicates with a mobile data communication system that transmits predetermined control data to a mobile body in which the shadowing is predicted to occur; Is received, the antenna is configured to have an antenna adjusting means for setting the antenna to a first height higher than the current height.
[0017]
In such a system, shadowing can be avoided by adjusting the antenna above the current height in response to control data from the mobile data communication system.
From the viewpoint of adjusting the height of the antenna according to the predicted start time of the occurrence of shadowing, the present invention provides the mobile-mounted communication device according to claim 8 as described in claim 9. The predetermined control data from the mobile data communication system includes a predicted time zone in which shadowing occurs, and the antenna adjusting means has a shadowing start timing detecting means for detecting a start time of the predicted time zone. When the shadowing start timing detecting means detects the start time of the prediction time zone, the antenna is set to the first height.
[0018]
Further, from the viewpoint of adjusting the height of the antenna in accordance with the predicted end time of occurrence of shadowing, the present invention provides the mobile-mounted communication device according to claim 9 as described in claim 9. The antenna adjusting means further has a shadowing end timing detecting means for detecting an end time of the predicted time zone, and when the shadow in end timing detecting means detects the end time of the predicted time zone. , And the antenna is configured to have a second height lower than the first height.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 2 is a principle diagram for preventing shadowing.
As shown in FIG. 2, in order to prevent shadowing, the control station 100 includes a prediction processing unit and a database that cooperates with the prediction processing unit. Thus, the shadowing time and the location of the vehicle B are predicted, and the predicted shadowing time of the vehicle B is notified in advance to the base station 200-1 that controls the location. Upon receiving the information from the control station 100, the base station 200-1 notifies the vehicle B of shadowing information including a time at which shadowing occurs. Vehicle B has in-vehicle device 300 and receives information from the base station. At a predicted time, the antenna control device 311 operates based on the shadowing information received from the base station 200-1 and the height of the vehicle B at which the antenna of the vehicle B can receive the radio wave from the base station 200-1 Set to.
[0020]
With this operation, the vehicle B can normally receive the information from the base station 200-1 even at the time when the predicted shadowing occurs.
The same components as those already described are denoted by the same reference numerals, and description thereof will be omitted.
Next, a system configuration for realizing the principle for preventing the shadowing shown in FIG. 2 will be described.
[0021]
FIG. 3 is a system configuration diagram.
As shown in FIG. 3, the mobile data communication system controls the base station 100 that predicts shadowing occurring in each vehicle and controls the base station, and controls each in-vehicle device 300 based on shadowing prediction information from the control station 100. And a vehicle-mounted device 300 that controls an antenna in accordance with shadowing prediction information from the base station 200.
[0022]
In the control station 100, the transceiver 140 acquires information from the base station 200. The information acquired by the transceiver 140 is analyzed by the control device 130 to determine whether it is vehicle information or information for predicting shadowing. Control device 130 controls to pass information to vehicle information processing unit 120 if the acquired information is vehicle information, and to pass information to prediction processing unit 160 if the acquired information is information for predicting shadowing. I do.
[0023]
The vehicle information processing unit 120 stores the information in the vehicle information DB based on the vehicle information received from the control device 130. Further, information corresponding to the search request from the control information 130 is extracted from the vehicle information DB and passed to the control information 130. The extracted information is transmitted by control device 130 to base station 200 via transceiver 140.
The prediction processing unit 160 analyzes information for predicting shadowing received from the control device 130, and controls the prediction information DB 150, the prediction information temporary DB 150-2, the storage DB 170, and the position prediction DB according to the information. Further, the prediction processing unit 160 transmits necessary information to the base station 200 based on the prediction of shadowing via the control device 130 and the transceiver 140.
[0024]
In the base station 200, the transceiver 210 transmits and receives information to and from the control station 100. The control device 220 analyzes an instruction or a request from the control station 100 and controls the vehicle position management processing unit 250.
The transceiver 230 transmits and receives information to and from the on-vehicle device 300 via an antenna. The control device 220 analyzes information with the vehicle-mounted device 300.
[0025]
The vehicle position management processing unit 250 stores the vehicle position information acquired from the on-vehicle device 300 in the vehicle position DB according to the instruction of the control device 220. In addition, the vehicle position management processing unit 250 extracts necessary information from the vehicle position DB in response to a request from the control device 220, and passes the information to the control device 220.
In the vehicle-mounted device 300, the transceiver 320 transmits and receives information to and from the base station 200 via the antenna 310. The control device 330 analyzes the information received from the base station 200, and controls the vehicle management unit 340 when the information is a vehicle information request. When the information received from base station 200 is shadowing prediction information, control device 330 controls shadowing prediction reception processing section 370.
[0026]
The vehicle management unit 340 extracts the vehicle information from the vehicle DB 350 according to the request of the control device 330, and passes the information to the control device 330. Control device 330 transmits the vehicle information acquired from vehicle management unit 340 to base station 200 by controlling transceiver 320 to respond to the vehicle information request from base station 200.
When receiving the shadowing prediction information from the control device 330, the shadowing prediction reception processing unit 370 stores the information in the prediction DB 380. Further, the shadowing prediction reception processing unit 370 displays on the preview message display unit 390 that shadowing is predicted based on the shadowing prediction information in the prediction DB. Further, the shadowing prediction reception processing unit 370 sets a timer 360 at a time when shadowing occurs based on the shadowing prediction information of the prediction DB. The timer 360 notifies the shadowing prediction reception processing unit 370 when the set time has elapsed. Shadowing prediction reception processing section 370 instructs antenna control apparatus 311 to raise the antenna.
[0027]
The antenna control device 311 controls the reception field strength meter 312 according to the instruction information of the shadowing prediction reception processing unit 370, sets the reception field strength meter 312 to an appropriate strength, and controls the antenna 310 to the designated height.
Next, the configuration of the database shown in FIG. 3 will be described.
FIG. 4 is a diagram illustrating an example of the vehicle information DB of the control station.
[0028]
As shown in FIG. 4, the vehicle information DB 110 includes a vehicle ID 4-1, a current time 4-2, a current position 4-3, a vehicle type 4-4, a vehicle size 4-5, an antenna maximum value 4-6, a destination. 4-7 and speed 4-8.
The vehicle information DB 110 is managed by the vehicle information processing unit 120.
The prediction processing unit 160 calculates the travel route of the vehicle with reference to the current position 4-3, the destination 4-7, and the speed 4-8.
[0029]
FIG. 5 is a diagram illustrating an example of the prediction information DB of the control station.
As shown in FIG. 5, the prediction information DB 150 includes a vehicle ID 5-1, a prediction start time 5-2, a prediction end time 5-3, an optimum antenna height 5-4, and a shadowing prevention 5-5. Is done.
The prediction information DB 150 is set by the prediction processing unit 160.
[0030]
FIG. 6 is a diagram illustrating an example of the storage DB 170 of the control station.
As shown in FIG. 6, the vehicle ID 6-1 includes a predicted start time 6-2, a predicted end time 6-3, and distribution data 6-4.
The storage DB 170 is a database for temporarily storing distribution data during the predicted start time 6-2 to the predicted end time 6-3 when shadowing cannot be prevented. After the prediction end time 6-3, the prediction processing unit 160 extracts the vehicle ID 6-1 and the stored distribution data 6-4, and the control device 130 transmits the distribution data 6-4 to the vehicle ID 6-1. You.
[0031]
FIG. 7 is a diagram illustrating an example of a vehicle position DB of a base station.
As shown in FIG. 7, the vehicle position DB 260 includes a vehicle ID 7-1 and a vehicle position 7-2.
The vehicle position DB 260 is a database that is controlled by the vehicle position management processing unit 250 and periodically acquires and updates vehicle information of each vehicle-mounted device in the area of the base station.
[0032]
FIG. 8 is a diagram illustrating an example of the prediction DB of the vehicle-mounted device.
As shown in FIG. 8, the prediction DB 380 includes a prediction start time 8-1, a prediction end time 8-2, and an optimum antenna height 8-3.
The prediction DB 380 is a database that stores predicted shadowing occurrence times and antenna heights sent from the control station via the base station.
[0033]
FIG. 9 is a diagram illustrating an example of the position prediction DB of the control station.
As shown in FIG. 9, the position prediction DB 180 is configured so that the vertical axis indicates the distance from the control station and the area of each base station, and the horizontal axis indicates time.
The prediction processing unit 160 analyzes the position prediction DB 180 and predicts when, where, and in which vehicle shadowing occurs.
[0034]
According to the example of FIG. 9, at time 8, vehicle A and vehicle B intersect in the area of base station C, and at time 9, vehicle C and vehicle D intersect at the area of base station D, causing shadowing. Then predict.
FIG. 10 is a diagram illustrating an example of the prediction information temporary DB of the control station.
As shown in FIG. 10, the prediction information temporary DB 150-2 includes a vehicle ID 10-1, a prediction time 10-2, an optimum antenna height 10-3, and a shadowing prevention 10-4.
[0035]
The prediction information temporary DB 150-2 is controlled by the prediction processing unit 160, and is later collected at the same time and converted into the prediction information DB 150.
Next, the operations of the supervising station, base station, and vehicle during shadowing will be described.
FIG. 11 is a sequence chart showing a control method at the time of shadowing.
Each of the vehicles A, B, and C extracts vehicle information such as a vehicle ID, a vehicle type, and a size from the vehicle DB 350 provided for each vehicle, and transmits the vehicle information to the control station via the base station in advance (S101).
[0036]
The base station periodically extracts the vehicle position information of each vehicle from the vehicle position DB 260, and notifies the supervising station of the information (S102).
In the control station, upon receiving vehicle information from each vehicle or receiving vehicle position information from the base station, the vehicle information processing unit 120 registers or changes the information in the vehicle information DB 110 (S103).
[0037]
The control station performs shadowing prediction by the prediction processing unit 160 from the acquired information (S104). For example, in the case of the example shown in FIG. 9, at time 8 between the vehicles A and B in the area of the base station C, and at time 9 between the vehicles C and D in the area of the base station D. Predicts that shadowing will occur.
The prediction processing unit 160 further analyzes whether or not shadowing can be avoided by adjusting the antenna. Information such as the sizes of the vehicles A and B and the maximum value of the antenna is extracted from the database and analyzed to determine whether shadowing prevention is possible or not. For example, when shadowing can be prevented by adjusting the height of the antenna of the vehicle B, shadowing information such as a predicted start time and end time of the shadowing and the height of the antenna is transmitted to the vehicle B (S105). . Details of the shadowing prediction processing will be described later.
[0038]
The shadowing prediction reception processing unit 370 of the vehicle B sets the estimated start time and end time of the shadowing in the timer 360 based on the received shadowing information (S107).
When the timer 360 notifies the shadowing prediction reception processing unit 370 of the scheduled start time of shadowing, the shadowing prediction reception processing unit 370 sets the antenna to the antenna control device 311 up to the height of the designated antenna. To instruct. The antenna control device 311 that has received the instruction sets the antenna 310 to the specified height (S108).
[0039]
When the timer 360 notifies the shadowing prediction reception processing unit 370 that the scheduled shadowing end time has come, the shadowing prediction reception processing unit 370 returns the antenna height to the antenna control device 311 so that the antenna height returns to the original height. Instruct. The antenna control device 311 having received the instruction returns the antenna 310 to the original height (S109).
[0040]
On the other hand, when the prediction processing unit 160 determines that the shadowing predicted to occur between the vehicle C and the vehicle D cannot be avoided by adjusting the antenna of the vehicle C, the prediction processing unit 160 The notice information for interrupting the communication due to shadowing is transmitted (S110).
When the shadowing prediction processing unit 370 of the vehicle C receives the advance notice information that the communication will be disconnected due to the shadowing, the shadowing prediction processing unit 370 displays on the advance message display unit 390 that the communication is disconnected.
[0041]
The control station stores the distribution data during the time when the communication of the vehicle C is predicted to be disconnected due to the shadowing, the predicted start time and the predicted end time of the shadowing, and the like in the storage DB 170 (S112).
The control station distributes the distribution data stored in the storage DB 170 to the vehicle C after the elapse of the estimated shadowing end time of the vehicle C (S113).
[0042]
After the elapse of the predicted shadowing end time, the vehicle C can receive the distribution data during the shadowing occurrence period (S114).
Next, a method of shadowing prediction processing will be described.
FIG. 12 is a sequence chart showing the shadowing prediction processing.
In the control station, the prediction processing unit 160 reads the current position 42, the destination 47, and the speed 48 from the vehicle information DB 110 using the vehicle ID of each vehicle as a key (S201).
[0043]
The prediction processing unit 160 stores the vehicle in the position prediction DB 180 on the assumption that the vehicle travels to the destination 47 at the same speed 48 (S202).
The prediction processing unit 160 uses the position prediction DB 180 to analyze whether or not another vehicle exists around the same point at the same time (S203). For example, according to the example illustrated in FIG. 9, it is understood that the vehicle A and the vehicle B exist in the area of the base station C at the same time 8. In the case of this example, the process proceeds to S204. If there is no other vehicle around the same point at the same time, the shadowing prediction processing ends.
[0044]
Next, when another vehicle is present around the same point at the same time, the size 45 of the corresponding vehicle is read from the vehicle information DB 110 to determine whether shadowing can be prevented (S204). For example, in the case of the vehicles A and B in the area of the base station C at the same time 8, the value of the size 45 of the vehicles A and B is read.
Since it is known that the vehicle A and the vehicle B exist in the area of the base station C at the same time 8, the prediction processing unit 160 determines that the vehicle B and the vehicle B Is analyzed, or whether the vehicle A is located on a straight line ahead of the antennas of the base station C and the vehicle B (S205). In this case, it is assumed that vehicle A is located on a straight line ahead of the antennas of base station C and vehicle B. At time 8, since it is determined that the vehicle A is located on a straight line ahead of the antennas of the base station C and the vehicle B, the process proceeds to S206. If there is no other vehicle on the straight line connecting the base station and the end of the vehicle antenna, the process returns to S208 to perform processing for the next time.
[0045]
Based on the above judgment, the values of the vehicle ID 10-1, the predicted start time 10-2, and the optimum height 10-3 of the antenna of the vehicle B are registered in the temporary predicted information DB 150-2.
Next, the prediction processing unit 160 reads the antenna maximum value 4-6 of the vehicle B from the vehicle information DB 110 in order to determine whether shadowing can be prevented (S207). It is determined whether or not the vehicle A is located on a straight line connecting the tip of the raised antenna (S208). If shadowing can be prevented by raising the antenna, the process proceeds to S210. If shadowing cannot be prevented, the process proceeds to S209.
[0046]
Here, it is assumed that the shadowing of the vehicle B can be prevented by raising the antenna. The value “OK” is set in the shadowing prevention 10-4 of the prediction information temporary DB 150-2 (S209).
The prediction processing unit 160 determines whether the above process has been performed for each base station at each time (S211). In this case, since the vehicle C and the vehicle D exist in the area of the base station D at the time 9, the process returns to S203 and performs the same processing until S207.
[0047]
Here, if shadowing occurs in the vehicle C and shadowing cannot be prevented even if the antenna of the vehicle C is raised to the highest value, the shadowing prevention 10- in the prediction information temporary DB 150-2 is performed. The value "impossible" is set to 4 (S210).
After finishing the processing for each base station at each time (S211), the prediction processing unit 160 determines that the time is continuous and the value of the shadowing prevention 10-4 is based on the data of the prediction information temporary DB. The same data is searched (S212). Data having a continuous time and the same value of the shadowing prevention 10-4 are combined into one data, converted into the format of the prediction information DB 150, and stored (S214). On the other hand, if the time is not continuous or the value of the shadowing prevention is not the same even if the time is continuous, each is stored in the prediction information DB 150 (S215).
[0048]
As described above, the data having the continuous time and the same value of the shadowing prevention 10-4 are combined into one data, so that the processing of S105 shown in FIG. Transmission can be performed efficiently.
Also, in the processing of S112 shown in FIG. 11, as the information for determining whether to save the distribution data during the time when the shadowing is predicted, the value of the propriety / impossibility of the shadowing prevention 5-5 of the prediction information DB 150 is referred. Is done.
[0049]
Eliminate data loss due to shadowing by predicting shadowing, analyzing the method of preventing shadowing based on the data of each vehicle, and notifying each vehicle in advance, as described above. Becomes possible.
Also, if the headquarters and the vehicle recognize the possibility of shadowing in advance, and if raising the antenna on the vehicle side can prevent shadowing, raise the antenna before shadowing occurs, and In the case where the ping cannot be prevented, more reliable data communication can be made possible by storing the data in the head office.
[0050]
【The invention's effect】
As described above, according to the first to seventh aspects of the present invention, it is possible to predict in advance shadowing that occurs due to the positional relationship between moving objects, and to prevent deterioration in communication quality. Further, loss of distribution data to a mobile body can be prevented even when communication is interrupted due to shadowing.
[0051]
Further, according to the inventions described in claims 8 to 10, since the moving object can adjust the antenna according to the start time and the end time at which the occurrence of shadowing is predicted, the communication quality can be improved. Can be prevented from deteriorating, and good communication can be maintained.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of a conventional mobile communication system.
FIG. 2 is a principle diagram for preventing shadowing.
FIG. 3 is a system configuration diagram.
FIG. 4 is a diagram illustrating an example of a vehicle information DB of a control station.
FIG. 5 is a diagram showing an example of a prediction information DB of the control station.
FIG. 6 is a diagram showing an example of a storage DB 170 of the control station.
FIG. 7 is a diagram illustrating an example of a vehicle position DB of a base station.
FIG. 8 is a diagram illustrating an example of a prediction DB of an in-vehicle device.
FIG. 9 is a diagram showing an example of a position prediction DB of the supervising station.
FIG. 10 is a diagram showing an example of a prediction information temporary DB of the control station.
FIG. 11 is a sequence chart showing a control method at the time of shadowing.
FIG. 12 is a sequence chart showing shadowing prediction processing.
[Explanation of symbols]
100 Administration Bureau
110 Vehicle information DB
120 Vehicle Information Processing Unit
130 control device
140 transceiver
150 Prediction information DB
160 prediction processing unit
170 Save DB
200 base stations
210 transceiver
220 control device
230 transceiver
240 antenna
250 Vehicle position management processing unit
260 Vehicle position DB
300 vehicle (vehicle equipment)
310 antenna
311 Antenna control device
312 Received electric field strength meter
320 transceiver
330 controller
340 Vehicle Management Department
350 vehicle DB
360 timer
370 Shadowing prediction reception processing unit
380 Prediction DB
390 Notice message display area

Claims (10)

In a mobile data communication system that communicates with a communication device mounted on a mobile present in a communication area,
Moving body information acquiring means for acquiring information on the size of the moving body present in the communication area,
Position predicting means for predicting the position of the moving object existing in the communication area;
Shadowing prediction means for predicting the occurrence of shadowing for communication with respect to each mobile based on the size and predicted position of each mobile;
A mobile data communication system comprising: a communication control unit that controls data communication with the mobile unit based on a result of prediction by the shadowing prediction unit. The mobile data communication system according to claim 1,
A mobile data communication system, wherein the mobile information obtaining means includes means for obtaining information on the size of each mobile from a database registered in advance. The mobile data communication system according to claim 1,
The above-mentioned position estimating means is a mobile object having a predicted position calculating means for calculating a predicted position of each mobile object based on information indicating a moving state of the mobile object transmitted from a communication device mounted on each mobile object Data communication system. The mobile data communication system according to any one of claims 1 to 3,
The above-mentioned communication control means, when a prediction result that shadowing occurrence is predicted by the shadowing prediction means is obtained, mounts the moving body on which the shadowing occurrence is predicted to the moving body. A mobile data communication system having antenna adjustment instructing means for transmitting control data for adjusting the height of an antenna of a communication device. The mobile data communication system according to claim 4,
The antenna adjustment instructing means, based on the predicted position of the moving object affected by shadowing in the area where the occurrence of shadowing is predicted, and information on the predicted position and size of the moving object affected by shadowing, There is an avoidance determining means for determining whether or not the shadowing can be avoided by adjusting the height of the antenna of the communication device of the moving body affected by the shadowing, and the avoidance determining means can avoid the shadowing. A mobile data communication system configured to transmit control data for adjusting the height of the antenna when it is determined. The mobile data communication system according to claim 5,
The communication control means further includes, when the avoidance determination means determines that the shadowing cannot be avoided, predicts that the occurrence of the shadowing will be data indicating that communication will be interrupted in a shadowing occurrence prediction time zone. A mobile data communication system having data transmission means for transmitting data to a mobile object to be transmitted. The mobile data communication system according to claim 5,
The communication control unit further includes a data holding unit that stores data to be delivered to the mobile unit in a storage unit during a predicted shadowing occurrence time period when the avoidance determination unit determines that the shadowing cannot be avoided. Control means;
A mobile data communication system having data distribution control means for distributing the data stored in the storage unit to the mobile body after the elapse of the predicted time period. A mobile data communication system for predicting the occurrence of shadowing based on the predicted position of each mobile in the communication area and transmitting predetermined control data to the mobile in which the shadowing is predicted to occur; In a mobile-mounted communication device that performs
A mobile-mounted communication device having antenna adjustment means for setting an antenna to a first height higher than a current height when receiving the predetermined control data from a mobile data communication system. The mobile-mounted communication device according to claim 8,
The predetermined control data from the mobile data communication system includes a predicted time zone in which shadowing occurs,
The antenna adjusting means has a shadowing start timing detecting means for detecting a start time of the predicted time zone. When the shadowing start timing detecting means detects the start time of the predicted time zone, the antenna adjusts. Mobile-mounted communication device with the first height. The mobile communication device according to claim 9,
The antenna adjustment unit further includes a shadowing end timing detecting unit that detects an end time of the predicted time zone, and when the end time of the predicted time zone is detected by the shadowing end timing detecting unit. A mobile-mounted communication device, wherein the antenna has a second height lower than the first height.

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