JP4549133B2 - Sampling method - Google Patents

Description

  The present invention relates to a technique for sampling vehicle information from an in-vehicle device.

  Conventionally, in an information management center, a technique for analyzing a traffic state in an arbitrary place such as a traffic jam based on a traveling state received from an in-vehicle terminal (hereinafter also referred to as an in-vehicle device) has been proposed (for example, see Patent Document 1). . In addition, traffic congestion monitoring using a fixed point camera and traffic congestion monitoring using sensors installed on the road are performed, both of which are analog. For this reason, the accuracy is low, and a time shift occurs in the transmission of information. In addition, there are many restrictions on installation.

  There is a further problem regarding the traffic monitoring technology using sensors (sound wave detection method) installed on the road. FIG. 14 is a diagram for explaining the problems of this sensor (detection method of sound waves and the like) in comparison with the wireless method.

  Although the method of grasping the passing state of vehicles using reflected waves such as sound waves over the road is still used, it is practically difficult to install infinitely on road facilities, where traffic congestion is likely, etc. The reality is that these are installed sequentially with priority. Because this method is pinpoint detection, if it was actually installed several tens of meters away from the accident car, the car will not pass at all, so it will be judged as if there is no traffic jam, or immediately after the traffic jam When installed, there is a problem that a traffic jam cannot be detected or a traffic jam in a section between sensors cannot be detected.

In view of the problem of the above-described sensor (detection method of sound waves, etc.), the present invention intends to monitor traffic congestion by a wireless method.
In this wireless system, there are a pattern in which each in-vehicle device is collectively called to collect vehicle information from each in-vehicle device, and a pattern in which the in-vehicle device is selectively called and vehicle information is collected from the called in-vehicle device. . FIG. 15 is a diagram for explaining the problem of the wireless system by comparing the pattern of simultaneous calling and the pattern of selective calling. As is clear from FIG. 15, the selective call is more desirable from the viewpoint of preventing interference.
JP 2002-208093 A

  An object of the present invention is to provide a technique for selectively calling a vehicle-mounted device and collecting (sampling) vehicle information from the called vehicle-mounted device from the viewpoint of preventing interference.

The present invention has been made to solve the above problems, and has the following configuration.
A method of sampling vehicle information from an in-vehicle device, the step of wirelessly transmitting information including a predetermined condition for the purpose of being received by the in-vehicle device, and the in-vehicle device including the predetermined condition according to its own position Receiving information, determining whether or not the predetermined condition is satisfied, and wirelessly transmitting information including vehicle information for the purpose of being received by the base station when it is determined that the predetermined condition is satisfied; Receiving information comprising: a sampling method comprising:

According to the present invention, when the in-vehicle device receives information including the predetermined condition according to its own position, determines whether the predetermined condition is satisfied, and determines that the predetermined condition is satisfied, the information including the vehicle information Will be transmitted wirelessly. Therefore, by appropriately setting the predetermined condition, it is possible to selectively call the in-vehicle device and collect (sample) the vehicle information from the in-vehicle device that has been called (only). Therefore, it is possible to prevent interference as compared with the case where all the in-vehicle devices respond. In addition, the processing load on the base station is reduced as compared with the case where all in-vehicle devices respond.

  In the sampling method, for example, the predetermined condition includes a first number for dividing the identification number of the in-vehicle device in the in-vehicle device that has received the predetermined condition, and a second number for comparison with the remainder thereof. The device divides its own identification number by the first number, compares the remainder with the second number, and determines that they are satisfied if they match.

This is an example of the predetermined condition. Therefore, it is possible to adopt other conditions as the predetermined conditions of the present invention.
In the sampling method, for example, the step of changing the first number based on the number of received information including the vehicle information and wirelessly transmitting the information including the first number after the change as the predetermined condition. Further prepare.

In this way, it is possible to obtain an appropriate number of responses (the number of received information including vehicle information) based on the passing amount of the vehicle (a vehicle equipped with an in-vehicle device).
The present invention can be specified as the invention of the system as follows.

  A system for sampling vehicle information from an in-vehicle device, a predetermined condition providing means for wirelessly transmitting information including a predetermined condition for the purpose of being received by the in-vehicle device, and information including the predetermined condition according to its own position An in-vehicle device that wirelessly transmits information including vehicle information and a collection unit that receives information including the vehicle information when it is determined that the predetermined condition is satisfied. A sampling system.

In the sampling system, for example, a base station may be further provided, and the predetermined condition providing unit and the collecting unit may be provided in the base station.
In the above sampling system, for example, the predetermined condition includes a first number for dividing the identification number of the in-vehicle device in the in-vehicle device that has received it, and a second number for comparing with the remainder, The in-vehicle device divides its own identification number by the first number, compares the remainder with the second number, and determines that they are satisfied if they match.

  In the sampling system, for example, the base station changes the first number based on the number of received information including the vehicle information, and includes information including the first number after the change as the predetermined condition. Wireless transmission.

Further, the present invention can be specified as the invention of the base station as follows.
The vehicle information is received from the in-vehicle device that wirelessly transmits the information including the vehicle information when the information including the predetermined condition is received according to the position of the user, and it is determined whether or not the predetermined condition is satisfied. A base station for sampling, comprising: a predetermined condition providing means for wirelessly transmitting information including the predetermined condition for the purpose of being received by the in-vehicle device; and a collecting means for receiving information including the vehicle information base station.

Further, the present invention can be specified as the invention of the base station as follows.
Means for receiving information including a predetermined condition according to its position, means for determining whether or not the predetermined condition is satisfied, means for wirelessly transmitting information including vehicle information when it is determined that the predetermined condition is satisfied; A vehicle-mounted device comprising:

Further, the present invention can be specified as the invention of the program as follows.
From the in-vehicle device that wirelessly transmits information including vehicle information when the computer receives information including a predetermined condition according to its position, determines whether or not the predetermined condition is satisfied, A base station that samples vehicle information, a predetermined condition providing unit that wirelessly transmits information including the predetermined condition for the purpose of being received by the in-vehicle device, and a collection unit that receives information including the vehicle information A program to make it work.

  Means for receiving information including a predetermined condition in accordance with the position of the computer, means for determining whether or not the predetermined condition is satisfied, means for wirelessly transmitting information including vehicle information when it is determined that the computer satisfies the condition; Program to function as.

  According to the present invention, from the viewpoint of preventing interference, it is possible to selectively call an on-vehicle device and collect (sample) vehicle information from the called on-vehicle device.

Hereinafter, a wireless communication system according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram for explaining a schematic system configuration of a radio communication system.

As shown in FIG. 1, the radio communication system includes an in-vehicle device 10, a radio base station 20, an information management center 30, and the like.
The in-vehicle device 10 is mounted on a vehicle, and has a function for performing wireless communication with the radio base station 20 (in-vehicle device for ETC in the present embodiment, not shown). Including. The in-vehicle device 10 includes a hard disk device that stores the determination program 11, in-vehicle information 12, and the like, a GPS receiver for detecting its own position, a memory, a CPU for controlling these, and the like (all not shown). )

  The in-vehicle device 10 may be configured as a single device, or may be configured as a device (system) that combines a plurality of devices (for example, an in-vehicle device for ETC and a car navigation device). In this way, it is possible to collect and provide information relatively easily by applying GPS / ETC terminals that are currently being installed in many vehicles. Note that the number of in-vehicle devices 10 can be an appropriate number, and FIG. 1 illustrates two vehicles (in-vehicle devices 10).

  The radio base station 20 is fixedly installed on the road side (or its surroundings), and includes a device having a function for performing wireless communication with the in-vehicle device 10. The radio base station 20 performs radio communication with the in-vehicle device 10 mounted on the vehicle located in the communication area. The radio base station 20 includes a relay program 21, a condition transmission program 22, a hard disk device that stores extraction condition information 23, a memory, a CPU for controlling these, and the like (all not shown).

The radio base station 20 may be configured as a single device, or may be configured as a device (system) combining a plurality of devices. At least one radio base station 20 is installed in the case of taking the form of a single station shown in FIG. 16, and at least two radio base stations 20 in the case of taking the form of a multi-station shown in FIG. FIG. 1 shows an example in which two radio base stations 20 are installed. According to a single station, if multiple samplings can be performed on the same (serial number) in-vehicle device 10 within the range of one station (wireless base station), the moving direction and moving speed can be easily determined. is there. In addition to the method of analyzing from the sampled log, a method of switching the operation mode and tracking a specific in-vehicle device 10 in real time can be realized.

  The multi-station method is used when measuring over longer spans, such as near interchanges with multiple highways, when there are many vehicles, or when you want to detect traffic jams other than those near the station. It is also possible to employ a mixture of single station and multi station.

  The information management center 30 is connected to the wireless base station 20 via a wired or wireless network, and is used to analyze traffic congestion based on information relayed from each in-vehicle device 10 via each wireless base station 20. Including devices. The information management center 30 also includes a hard disk device that stores the analysis program 31, analysis information 32, map information 33, and the like, a memory, and a CPU for controlling these (all not shown).

The information management center 30 may be configured as a single device, or may be configured as a device (system) that combines a plurality of devices.
(Overview of operation)
Next, the operation of the radio communication system having the above configuration will be described with reference to the drawings.

2 and 3 are sequence diagrams for explaining the operation of the wireless communication system.
As shown in FIG. 2, the radio base station 20 is subject to analysis target determination data (exemplified by the radio base illustrated in FIG. The station serial number, numerical value Nr, constant Nb.) Is wirelessly transmitted (broadcast) (S10).

  The in-vehicle device 10 receives analysis target determination data transmitted from the radio base station 20 according to its own position, that is, when the vehicle on which the vehicle is mounted is located in the communication area of the radio communication base station 20. (S11).

The in-vehicle device 10 identifies the vehicle to be analyzed based on the analysis target determination data (S12). That is, the in-vehicle device 10 determines whether or not it is an analysis target.
This determination is performed as follows, for example.

  The in-vehicle device 10 obtains its own serial number (stored in its own memory or the like, which corresponds to its own identification number of the present invention), and the serial number is a constant Nb included in the analysis target determination data received earlier. Find the remainder by dividing. Then, the remainder value is compared with the numerical value Nr, and if both are the same, it is determined that the self is an analysis target. On the other hand, if both are not the same, it judges that self is not a subject of analysis. In the latter case, it waits for data reception from the radio base station 20, and repeats the processing from S11 again.

  If the result of the determination in S12 is that it is determined that it is the subject of analysis, the in-vehicle device 10 acquires GPS information and receives it in the analysis target data (FIG. 18B) for the purpose of receiving it by the radio base station 20. The illustrated in-vehicle device serial number, GPS information, and wireless base station serial number) are wirelessly transmitted (broadcast) (S13).

  In this way, the in-vehicle device 10 performs the determination of S12, and as a result, only the specific in-vehicle device 10 reacts and wirelessly transmits the analysis target data. Therefore, by appropriately setting the analysis target determination data (details will be described later), it is possible to selectively call the in-vehicle device 10 and (only) collect (sample) vehicle information from the in-vehicle device 10 that has called it. It becomes. Therefore, it is possible to prevent interference as compared to the case where all the in-vehicle devices 10 respond.

In other words, when broadcasting is simply performed, terminals within the range return ack at the same time, causing interference, but to prevent this, it transmits with a predetermined condition (filtering condition), and only terminals that match the condition It is a mechanism to answer back. This eliminates the need to create a gate, run under the directional beam at a low speed, and adopt a system that samples all cars, so it can be realized at low cost and it is possible to grasp the running state without disturbing normal running It has become.

The radio base station 20 receives the analysis target data transmitted from the in-vehicle device 10 (S14).
The radio base station 20 records the reception time of the analysis target data and specifies the analysis target data (S15). That is, the radio base station 20 determines whether the analysis target data is an analysis target.

This determination is performed as follows, for example.
The radio base station 20 acquires its own serial number (a serial number (or sequence number or ID) stored in its own memory or the like) and includes the serial number and the analysis target data received earlier. Compare the station serial number. As a result, if both are the same, it is determined that the analysis target data is the analysis target, and the radio base station 20 determines that the in-vehicle device serial number, the GPS information, the radio base station serial number, the reception time (FIG. 18B). (Reference) is transmitted to the information management center 30 (one-to-one communication) (S16).

On the other hand, if the two are not the same, it is determined that the analysis target data is not the analysis target, and the radio base station 20 discards the analysis target data.
The information management center 30 receives the in-vehicle device serial number, GPS information, wireless base station serial number, and reception time transmitted from each wireless base station 20, and accumulates them (S17).

  The information management center 30 analyzes the accumulated data (S18). For example, in the case of a single station installation form, the information management center 30 calculates movement information for each in-vehicle device serial number within the radio base station serial number from the accumulated data. Then, if the calculated movement information is less than a certain movement amount, it is determined that there is a traffic jam. Similarly, in the case of a multi-station installation form, the information management center 30 moves from the stored data for each same in-vehicle device serial number between a specific radio base station serial number and another radio base station serial number. Calculate information. Then, if the calculated movement information is less than a certain movement amount, it is determined that there is a traffic jam.

As shown in FIG. 3, the information management center 30 transmits data of the analysis result to the radio base station 20 (one-to-one communication) (S19).
The radio base station 20 receives the analysis result data transmitted from the information management center 30 (S20), and wirelessly transmits (broadcasts) the analysis result data to be received by the in-vehicle device 10 (S21).

The in-vehicle device 10 receives the analysis result data transmitted from the radio base station 20 and notifies the traffic jam location based on the analysis result data, for example, the traffic jam location display, the traffic jam status display, the traffic jam location, Outputs synthesized speech about traffic conditions.
(Operation details)
Next, operation details of the radio communication system having the above-described configuration will be described with reference to the drawings. (Condition transmission processing by the radio base station 20)
FIG. 4 is a flowchart for explaining the operation of the radio base station 20. FIG. 5 is an example of setting values of the radio base station 20.

  The radio base station 20 executes the condition transmission process shown in FIG. 4, that is, the extraction condition setting (S 30) and the extraction condition transmission (S 31), when the CPU executes the condition transmission program 22 and the like read therein. .

  As shown in FIG. 5, the extraction condition setting (S30) is a process of setting a transmission interval send_int (S301), a selection condition 1pkup_div (S302), a selection condition 2pkup_mod (S303), and an operation mode mode (S304). is there. These settings are performed manually by a user (for example, a person related to a base station), for example.

  At the transmission interval send_int (for example, transmission once every 0.5 seconds) set as described above, the radio base station 20 selects the selection condition 1pkup_div set as described above (Nb in FIG. 18A). Equivalent) and selection condition 2pkup_mod (corresponding to Nr in FIG. 18A) is set to the format shown in FIG. 6B and wirelessly transmitted (S31). The transmission interval is determined, for example, whether transmission is performed every 3 seconds, every 30 seconds, or irregularly. If the transmission interval is simply shortened, more information may be acquired. Next, two selection conditions are set (S302, S303).

  Condition 2 determines a so-called divisor, but if it is large, the number of samples that can be sampled (expecting an answer back) decreases, but the possibility of interference decreases. Large when there are many terminals (vehicles) in the vicinity. If you want to sample different groups even with the same divisor, change the remainder to be given. The operation mode is for expansion when performing real-time tracking for a specific terminal.

The header part includes items (msg_type, sequence_no, stataon_add, destination_add, date, time, class) shown in FIG.
The acquisition purpose is set in msg_type. In sequence_no, a broadcast sequence number is assigned to each base station (used for analysis of answerback data). A unique address is assigned to each station in staton_add. In distination_add, 0 is input in the case of broadcasting, and a serial number is input when calling an individual terminal. date is used for speed detection and the like (accurately acquired from GPS). Time is used for speed detection or the like (accurately acquired from GPS). The type of vehicle type information is set in class.
(Judgment processing by the in-vehicle device 10)
7 and 8 are diagrams for explaining the operation of the in-vehicle device 10.

The in-vehicle device 10 performs the determination process shown in FIG. 7 by the CPU executing the determination program or the like read into the vehicle-mounted device 10.
The in-vehicle device 10 corresponds to its own position, that is, when the vehicle on which it is mounted is located in the communication area of the radio communication base station 20, the in-vehicle device 10 is transmitted from the radio base station 20 to FIG. The indicated data is received (S40).

The in-vehicle device 10 obtains (reads) its own in-vehicle device sequence number from its own memory or the like (S41), and divides the in-vehicle device sequence number by the selection condition 1pkup_div included in the data received in S40 earlier to obtain a remainder. (S42). The in-vehicle device 10 compares the remainder with the selection condition 2pkup_mod included in the data received in S40 earlier (S43). And if both are the same (S43: Yes), the date date, time time, latitude latitude, and longitude longitude from its own GPS receiver, and its own in-vehicle device serial number from its own memory etc. Serial is acquired, these are set in the format shown in FIG. 6C (S44), and wireless transmission (answerback) is performed (S45). This header portion includes items (msg_type, sequence_no, statin_add, destination_add, date, time, class) shown in FIG.

  In this way, the in-vehicle device 10 determines whether or not the conditions 1 and 2 wirelessly transmitted from the radio base station 20 are satisfied (S42, S43), and performs answer back only when the conditions are satisfied (S43: Yes) ( S44, S45). This operation will be described with reference to FIG.

  In FIG. 8, the radio base station 20 sets the selection condition 1pkup_div and the selection condition 2pkup_mod to the format shown in FIG. 6B at a transmission interval send_int (for example, transmission once every 0.5 seconds). It shows a state in which each of the in-vehicle devices 10 (five in-vehicle devices 10) is receiving data transmitted from the radio base station 20. In addition, the number in the box showing each vehicle-mounted apparatus 10 shows the vehicle-mounted apparatus sequence number which each vehicle-mounted apparatus 10 hold | maintains in the memory.

  Here, for example, if the selection condition 1 pkup_div = 10 and the selection condition 2 pkup_mod = 2 (that is, two in-vehicle devices 10 divided by 10), the in-vehicle device sequence number remaining by dividing by 10 is only 042. Only the in-vehicle device 10 with the device sequence number 042 is determined to satisfy (S43: Yes), and the answerback is performed.

  Also, for example, if selection condition 1 = 399 and selection condition 2 = 0 (that is, in-vehicle device 10 with 0 remaining divided by 399), the in-vehicle device sequence number with 0 remaining after dividing by 399 is only 399. Only the in-vehicle device 10 having the sequence of 399 is determined to satisfy (S43: Yes), and the answerback is performed. When the divisor is the same as the serial number and the remainder is 0 as in this example, it can be used as the “specific terminal tracking mode”.

  As described above, the in-vehicle device 10 determines whether or not the conditions 1 and 2 wirelessly transmitted from the radio base station 20 are satisfied (S42 and S43), and performs answer-back only when the conditions are satisfied (S43: Yes). It has become. Therefore, an answer back can be obtained only from the specific in-vehicle device 10 by setting the conditions 1 and 2 to an appropriate number. Therefore, it is possible to prevent interference as compared with the case where answerbacks are obtained from all the in-vehicle devices 10.

  Further, depending on how the conditions 1 and 2 are set, a plurality of groups to answer back can be created. For example, condition 1 = 100, condition 2 = 3 (that is, 3 remaining in-vehicle devices 10 divided by 100), condition 1 = 100, condition 2 = 6 (that is, 6 remaining in-vehicle devices 10 divided by 100), and so on. It is possible to set. This means that two of the 100 in-vehicle devices 10 answer back.

  In the above example, the example in which the answer-back is performed only when the in-vehicle device 10 satisfies the conditions 1 and 2 wirelessly transmitted from the radio base station 20 has been described. For example, the condition for answer-back is further added. It is also possible to do.

9 further adds to the condition of S43 shown in FIG. 7 whether or not the conditions (msg_type and Distination_add) wirelessly transmitted from the radio base station 20 correspond to itself (S46), and the condition (msg_type and When (Distination_add) corresponds to self (S46: Yes), the answerback is performed.

As described above, various conditions can be adopted as the predetermined condition of the present invention.
For example, in S304 in Fig. 5, the operation mode (the operation mode is data for designating a specific type of vehicle or vehicle type (for example, bus, truck, passenger car, large vehicle, small vehicle). Therefore, it is possible to obtain an answer back only from a specific type of vehicle.) In the in-vehicle device 10, the vehicle type identification information stored in its own memory or the like and its operation mode It is also possible to adopt a condition for answering back only when the two match.
(Relay processing by the radio base station 20)
FIG. 10 is a diagram for explaining the operation of the radio base station 20.

The radio base station 20 performs the relay process shown in FIG. 10 when the CPU executes the relay program or the like read into the radio base station 20.
The wireless base station 20 receives the data shown in FIG. 6C that is wirelessly transmitted (answerback) from the in-vehicle device 10 (S50). The radio base station 20 divides the in-vehicle sequence number included in the unserved data by the selection condition 1pkup_div set in S30 in FIG. 4 to obtain a remainder (S51). The radio base station 20 compares the remainder with the selection condition 2pkup_mod set in S30 in FIG. 4 (S52). Then, if both are the same (S52: Yes), the wireless base station 20 is wirelessly transmitted (answerback) from the in-vehicle device 10 as setting of analysis target information (S53), as shown in FIG. Set the data as is. Thereafter, the radio base station 20 transmits the set analysis target information to the information management center 30 (S54).
(Analysis processing by the information management center 30)
FIG. 11 is a diagram for explaining the operation of the information management center 30.

The information management center 30 performs the analysis processing shown in FIG. 11 when the CPU executes the analysis program read into the information management center 30.
The information management center 30 receives the analysis target information transmitted from the radio base station 20 (S60). The information management center 30 determines whether or not the in-vehicle device sequence number included in the analysis target information is in its own database (S61). If not (S61: No), the analysis target information is stored in its own database. (S62). For example, when a specific in-vehicle device 10 answers for the first time, as a matter of course, in S61, it is not determined that the in-vehicle device sequence number is in its own database.

  On the other hand, if the in-vehicle device sequence number included in the analysis target information received in S60 is stored in its own database (S61: Yes), the travel information is calculated (S63). That is, the distance between both is calculated based on the latitude and longitude included in the analysis target information received this time and the latitude and longitude included in the analysis target information accumulated last time. In calculating this distance, it may be possible to calculate the distance on the map more accurately by referring to the map information (S64).

  Next, based on the Time included in the analysis target information received this time and the Time included in the previously stored analysis target information, the passage time between the two is calculated, and then, based on the previously calculated distance and the passage time. The average speed between them is calculated. In this way, analysis is performed. In addition, since the above analysis is an example, it is also possible to analyze by another method.

Next, an example of traffic jam analysis between radio base stations (hereinafter also referred to as stations) XY will be described with reference to FIG.
FIG. 12 is a diagram for explaining the operation of the information management center 30. In the following description, it is assumed that the radio base station 20 is arranged at X and Y positions (multi-station) as shown in FIG. As shown in FIG. 16, even a single station can be operated in the same manner.

The information management center 30 performs the analysis processing shown in FIG. 12 when the CPU executes the analysis program read into the information management center 30. The information management center 30 receives the analysis target information transmitted from each radio base station 20 (each radio base station 20 arranged at the X and Y positions in FIG. 17), and stores this information in the log of each radio base station 20. Are recorded (accumulated).

  The information management center 30 extracts one data from the log of the specific radio base station 20 (in FIG. 12, the radio base station X is exemplified) (S70), and the other radio base station 20 (in FIG. 12, the radio base station Y is exemplified). ) Of the corresponding in-vehicle device serial number is searched from the log (S71).

  As a result, if there is a corresponding in-vehicle device serial number (S72: present), the distance between the two is calculated (S73). This is calculated based on the latitude and longitude included in the data extracted from the log of the specific radio base station 20 and the latitude and longitude included in the data corresponding to the corresponding serial in the log of the other radio base station 20. When calculating this distance, it may be possible to accurately calculate the distance on the map using map information.

  Next, the average speed between them is calculated (S74). First, the transit time is calculated based on the Time included in the data extracted from the log of the specific radio base station 20 and the Time included in the data corresponding to the corresponding serial in the log of the other radio base station 20. Next, the average speed between the two is calculated from the distance calculated earlier and the passing time. These calculation results can be provided to the in-vehicle device 10 as analysis result data and used as described with reference to FIG.

FIG. 19 shows an actual application example of the present embodiment.
(Automatic parameter change algorithm)
In the above example, the setting of the selection condition 1pkup_div has been described as being manually input by a user (for example, a person related to the base station), but for example, by the following algorithm (an algorithm that automatically changes the number of samples) It is possible to automatically change the selection condition 1pkup_div.

Hereinafter, on a certain road, it is assumed that the number of samples of about 1/100 from the area of a normal radio base station (also referred to as a station) 20 is acquired as a reference. Usually, it is assumed that there is no interference. It is assumed that a traffic jam occurs in the vicinity of the station 20 and a larger number of vehicles stay in the area, and the possibility of interference is likely to increase.

This station 20 takes the following method as a method of grasping the possibility of traffic jam without performing traffic jam analysis from the log.
1) Even when sampling is normally performed for 1/100 units, the number of selection conditions pkup_mod for the selection condition pkup_div = 100 (here, five types of 8, 13, 29, 43, 77 are used as examples) is recursive. (S80 to S89).
2) The expected value is that ack (ack from the in-vehicle device 10) for three types of pkup_mod returns about 1 (S91: pkup_div = specified value). (S92: 3 <number of ack) The number of terminals in the area may be increasing. If the increase continues, data cannot be acquired due to interference, so pkup_div is changed to 200, for example (S93). Here, it is assumed that the change is doubled or ½, but a continuous value or a table for increasing / decreasing pkup_div may be prepared.
3) If the acquisition continues and ackup_div = 200 further returns about 3 ack (S92: 3 <number of ack), pkup_div is further increased.
4) On the contrary, if acquisition is continued and ack is continuously 0 (S92: number of ack = 0), pkup_div is decreased (decreased to 1/2 in FIG. 13) (S94).

The advantages of this algorithm are as follows. First, it is possible to avoid interference even if there is a significant increase in ack with respect to the specified and expected values. Second, it can be changed automatically without human intervention, so 24-hour monitoring and manual parameter changes are not required. Third, if pkup_div is increased, it is not necessary to change the expected number of samples relative to the population if the type of pkup_mod is also increased at the same magnification. Fourth, if the number of terminals in the area decreases, it can be automatically returned to the specified value.

  The privacy problem can be solved by taking a random in-vehicle device 10 serial number each time the power is turned on. Since traffic information can be acquired up to "how many kilometers per hour", a more detailed service is possible. Even if you take a break at SA on the way of an expressway, you can be more accurate by placing station 20 in SA. Also, when the numerical value is significantly different from the average (cause of vehicle failure, etc.), it can be avoided by the process of separating from the aggregated data as an exception.

The wireless communication system according to the present embodiment has the following effects. First, it is possible to obtain more accurate traffic jam information. Secondly, it is possible to bypass the location where the cars are concentrated. Thirdly, the use of the wireless device 20 improves the degree of freedom of installation location, and makes it unnecessary to install sensors in each lane. Fifth, existing car navigation devices and ETC devices can be used. Sixth, the in-vehicle device 10 can receive traffic jam information from the radio base station. Furthermore, a rough movement route can be grasped by using the map information.

  The present invention can be implemented in various other forms without departing from the spirit or main features thereof. For this reason, said embodiment is only a mere illustration in all points. The present invention is not construed as being limited by these descriptions.

The present invention can also be specified as follows.
(Supplementary Note 1) A method of sampling vehicle information from an in-vehicle device, the step of wirelessly transmitting information including a predetermined condition for the purpose of being received by the in-vehicle device, and the in-vehicle device according to its position Receiving information including a predetermined condition, determining whether or not the predetermined condition is satisfied, and wirelessly transmitting information including vehicle information when determining that the predetermined condition is satisfied; and receiving information including the vehicle information A sampling method comprising: (1)
(Supplementary Note 2) The predetermined condition includes a first number for dividing the identification number of the in-vehicle device in the in-vehicle device that has received it, and a second number for comparison with the remainder, The sampling method according to appendix 1, wherein a self-identification number is divided by the first number, the remainder is compared with the second number, and the two are matched and determined to be satisfied. (2) (Appendix 3) The method further includes a step of changing the first number based on the number of received information including the vehicle information, and wirelessly transmitting information including the changed first number as the predetermined condition. The sampling method according to Appendix 2. (3)
(Additional remark 4) It is a system which samples vehicle information from a vehicle-mounted apparatus, Comprising: The predetermined condition provision means which wirelessly transmits the information containing a predetermined condition for the purpose of being received by the vehicle-mounted apparatus, and the predetermined according to its own position The information including the condition is received, it is determined whether or not the predetermined condition is satisfied, and when it is determined that the condition is satisfied, the in-vehicle device that wirelessly transmits the information including the vehicle information, and the collection that receives the information including the vehicle information And a sampling system.
(Supplementary Note 5) The sampling system according to Supplementary Note 4, further comprising a base station, wherein the predetermined condition providing unit and the collecting unit are provided in the base station.
(Supplementary Note 6) The predetermined condition includes a first number for dividing the identification number of the in-vehicle device in the in-vehicle device that has received the predetermined condition, and a second number for comparison with the remainder thereof. 6. The sampling system according to appendix 4 or 5, wherein a self-identification number is divided by the first number, the remainder is compared with the second number, and if both match, it is determined to satisfy.
(Additional remark 7) The said base station changes the said 1st number based on the number of reception of the information containing the said vehicle information, The wireless transmission of the information containing the changed 1st number as said predetermined condition is carried out. 6
The sampling system described in.
(Supplementary Note 8) From an in-vehicle device that wirelessly transmits information including vehicle information when it receives information including a predetermined condition according to its own position, determines whether or not the predetermined condition is satisfied, and satisfies the predetermined condition. A base station for sampling vehicle information, a predetermined condition providing means for wirelessly transmitting information including the predetermined condition for the purpose of being received by the in-vehicle device, and a collecting means for receiving information including the vehicle information And a base station. (4)
(Supplementary Note 9) Means for receiving information including a predetermined condition according to its own position, means for determining whether or not the predetermined condition is satisfied, and wirelessly transmitting information including vehicle information when it is determined that the predetermined condition is satisfied A vehicle-mounted device comprising: (5)
(Supplementary note 10) The computer receives information including a predetermined condition according to its own position, determines whether or not the predetermined condition is satisfied, and wirelessly transmits information including vehicle information when it is determined that the predetermined condition is satisfied. A base station that samples vehicle information from an in-vehicle device, and a predetermined condition providing unit that wirelessly transmits information including the predetermined condition for reception by the in-vehicle device, and receives information including the vehicle information A program for functioning as a collection means.
(Supplementary Note 11) Means for receiving information including a predetermined condition in accordance with the position of the computer, means for determining whether or not the predetermined condition is satisfied, and wirelessly transmitting information including vehicle information when it is determined that the predetermined condition is satisfied A program for functioning as a transmission means.

  According to the present invention, from the viewpoint of preventing interference, it is possible to selectively call an on-vehicle device and collect (sample) vehicle information from the called on-vehicle device.

It is a schematic block diagram of the radio | wireless communications system which is one Embodiment of this invention. It is a sequence diagram for demonstrating operation | movement of the radio | wireless communications system which is one Embodiment of this invention. It is a sequence diagram for demonstrating operation | movement of the radio | wireless communications system which is one Embodiment of this invention. 4 is a flowchart for explaining the operation of a radio base station 20; 4 is a flowchart for explaining the operation of a radio base station 20; It is an example of a data format transmitted / received between the base station 20 and the vehicle-mounted device 10. 4 is a flowchart for explaining the operation of the in-vehicle device 10; 4 is a flowchart for explaining the operation of the in-vehicle device 10; 4 is a flowchart for explaining the operation of the in-vehicle device 10; 4 is a flowchart for explaining the operation of a base station 20. 5 is a flowchart for explaining the operation of the information management center 30. 5 is a flowchart for explaining the operation of the information management center 30. 4 is a flowchart for explaining the operation of a base station 20. It is a figure for demonstrating the problem of detection methods, such as a sound wave. It is a figure for demonstrating the problem of a radio system. It is a figure for demonstrating a single station. It is a figure for demonstrating a multi station. It is an example of a data format transmitted / received between the base station 20 and the vehicle-mounted device 10. It is a figure for demonstrating the example of application of a radio | wireless communications system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 In-vehicle apparatus 11 Determination program 12 In-vehicle information 20 Wireless base station 21 Relay program 22 Condition transmission program 23 Condition extraction information 30 Information management center 31 Analysis program 32 Analysis information 33 Map information

Claims (5)

A method of sampling vehicle information from an in-vehicle device,
Wirelessly transmitting information including the first number and the second number for the purpose of being received by the in-vehicle device;
The in-vehicle device receives information including the first number and the second number according to its position , divides its own identification number by the first number, and the remainder in the division and the second number are Determining whether or not to match, and determining that the remainder and the second number match , wirelessly transmitting information including vehicle information; and
Receiving information including the vehicle information;
A sampling method comprising: Based on the number of received information including the vehicle information, and change the first digit, further comprising information that includes a first digit after the change to wireless transmission,
The sampling method according to claim 1 . A base station for sampling the car mounting device or al car both information,
For the purpose of being received by the in-vehicle device, the in-vehicle device wirelessly transmits information including a first number for dividing its own identification number and a second number for comparison with the remainder in the division. Condition providing means;
Collecting means for receiving information including the vehicle information wirelessly transmitted by the in-vehicle device when it is determined that the remainder and the second number match ;
A base station comprising: The predetermined condition providing unit changes the first number based on the number of received information including the vehicle information, and wirelessly transmits the information including the first number after the change.
The base station according to claim 3. It means for receiving in response information including first digit and second digit in its position,
Means for dividing a self-identification number by the first number and determining whether or not the remainder in the division matches the second number ;
Means for wirelessly transmitting information including vehicle information when it is determined that the remainder and the second number match ;
A vehicle-mounted device comprising:

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