JP2012199816A - Data reception device and data reception program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable divided data to be certainly received while significantly utilizing a recording area in a data reception device.SOLUTION: A DSRC in-vehicle device: receives transmission data transmitted from an on-road machine (S110); and stores each data included in each packet of the received transmission data, by dividing up the data into each type of the data, in a storage part having a plurality of assembly buffers whose number is set to be equal to or smaller than the maximum number of the packets capable of being included in the transmission data of single transmission regulated based on a standard of the on-road machine (S130 to S260); determines whether or not the divided data is complete in each assembly buffer in which the data is stored based on reconstruction information (S270); and combines and outputs the divided data based on the reconstruction information when it is determined that the divided data is complete (S280). Thereby, the DSRC in-vehicle device can receive newly received divided data without disposing of divided data received previously.

Description

  The present invention relates to a data receiving apparatus capable of receiving transmission data transmitted from a data transmitting apparatus, and a data receiving program.

  Conventionally, a dedicated narrow area communication (DSRC) technique has been standardized (for example, see Non-Patent Document 1). In this standard, data to be transmitted by a data transmission device is divided into a plurality of packets of a predetermined length and transmitted, and a data reception device includes a predetermined number of recording areas prepared for each type of data in each packet. The data is sorted and recorded, and when all the divided data (divided data) is prepared, the data is restored and output. At this time, the data in the recording area where the corresponding data was recorded is deleted.

Narrowband Communication (DSRC) Application Sublayer Standard, ARIB STD-T88 1.1 Edition, Radio Industries Association (see p.28: 3.2.2.4.2 Bulk Transfer Control Procedures, etc.)

  By the way, in the above standard, the data transmission device repeatedly transmits data to be transmitted in consideration of the situation where the data reception device cannot receive data, or the data transmission device performs data transmission in response to a request from the data reception device. It is configured to retransmit (divided data). In this configuration, a recording area for temporarily recording the divided data is required for each type of data until all of the same kind of divided data is received. It is not defined in the above standard.

  Here, when the number of the recording areas is too small, new types of data may be received one after another before the restoration of the divided data is completed. In this case, the data is recorded in the recording area. Since data of a new type cannot be recorded unless the data is deleted, there is a problem that data that cannot be received occurs. Also, when the number of recording areas is large, there is a low possibility that unreceivable data will be generated, but there is a high possibility that there are recording areas that are not used, and there is a problem that the recording areas cannot be used meaningfully. .

  Therefore, in view of such problems, in the data receiving apparatus and the data receiving program capable of receiving the transmission data transmitted from the data transmitting apparatus, it is possible to reliably receive the divided data while using the recording area meaningfully. It is an object of the present invention to do this.

  In the data receiving device having the first configuration configured to achieve the above object, the receiving unit receives the transmission data transmitted from the data transmitting device, and the distribution storing unit receives each packet of the received transmission data. Each data included in each data type for a recording unit having a plurality of recording areas set to a number equal to or less than the maximum number of packets that can be included in one transmission data according to the standard of the data transmission apparatus. Sort and store. The restoration possibility determining means determines whether or not the divided data is prepared in each recording area where the data is recorded by the distribution storage means based on the restoration information, and the combined output means determines whether the restoration output possibility determination means When it is determined that all the data are aligned, the divided data are combined and output based on the restoration information.

  Here, when sending transmission data from the data transmitting apparatus to the data receiving apparatus, for example, a certain type of divided data is continuously transmitted, and when transmission of this type of divided data ends, the next type of divided data is transmitted. It can be considered that the divided data is continuously transmitted. In this configuration, if the transmission data can be normally received normally, one recording area is sufficient. However, when the transmission data is transmitted and received wirelessly, the communication state becomes unstable and the transmission data cannot be received normally. In some cases, if there is only one recording area, data that cannot be received normally is generated.

  In other words, if some of the divided data of the transmission data cannot be received normally, the divided data that has not been combined remains recorded in the recording area, and another type of divided data is newly added. Even if it is received, there is no recording area. In order to receive a new type of divided data in this state, it is necessary to overwrite the recording area, and the previously received divided data is discarded.

  Therefore, in the present invention, a plurality of recording areas are set, and even if a part of a certain type of divided data cannot be received normally, even if another type of divided data is newly received, By recording the newly received divided data in the area, the newly received divided data can be received without discarding the previously received divided data. In this configuration, the previously received divided data is held in the recording area, and when the divided data that could not be received is retransmitted, it can be combined (restored) with the original data.

  By the way, it is not a configuration in which divided data of a certain type is continuously transmitted and when the data of this type is completed, the divided data of the next type is continuously transmitted. It is also possible to assume a configuration in which one is included in the transmission data and transmitted. For example, the first divided data of type A and the first divided data of type B are included in the first transmission data and transmitted, and the second divided data of type A and the second divided data of type B are 2 This is a case where transmission is included in the second transmission data.

  In this case, since the number of data types is the maximum number of packets that can be included in one transmission data, in the present invention, the upper limit value of the number of recording areas can be included in one transmission data. The maximum number of packets that can be made.

According to such a data receiving apparatus, it is possible to improve the probability that the divided data can be received without providing a useless recording area.
By the way, in the data receiving apparatus, as in the second configuration, the data receiving apparatus includes an initialization unit that initializes a recording area in which the combined data is recorded, and the distribution storage unit includes a new type of data. May be preferentially allocated to the initialized recording area.

According to such a data receiving apparatus, it is possible to make it difficult to delete data before combining.
Further, in the data receiving device, as in the third configuration, the distribution storage means has the longest time when there is no recording area initialized when a new type of data is received. A new type of data may be overwritten in a recording area where data has not been updated.

  According to such a data receiving apparatus, it is possible to discard data that has not been combined for a long time. As a result, it is possible to eliminate the state where the recording area is not updated for a long time.

  In the data receiving apparatus, as in the fourth configuration, the distribution storing means is set to the same number as the maximum number of packets that can be included in one transmission data in accordance with the standard of the data transmitting apparatus. You may make it arrange | position and store for every kind of data with respect to the recording part which has a some recording area.

According to such a data receiving apparatus, it is possible to reduce data discarded without being combined.
Alternatively, in the data receiving apparatus, when the transmission data includes information on the number of packets included in the transmission data as in the fifth configuration, the number of recording areas is set to the same number as the number of packets. An area number setting unit may be provided.

  According to such a data receiving apparatus, the number of recording areas can be dynamically set by the number of data types that can be transmitted by one transmission data. Therefore, when setting the number of recording areas to be small, recording areas that are not used can be used for other purposes.

Further, the data receiving apparatus may be configured as a DSRC wireless communication apparatus as in the sixth configuration.
According to such a data receiving device, it is possible to satisfactorily receive transmission data from a device that performs communication with the DSRC wireless communication device.

  Next, a data reception program as a seventh configuration made to achieve the above object is a program for causing a computer to function as each means constituting the data reception device according to any one of the above items It is characterized by being.

  According to such a data receiving program, at least the same effect as that of the data receiving apparatus according to claim 1 can be enjoyed.

1 is a block diagram showing a schematic configuration of a communication system 1. FIG. It is a schematic diagram which shows the outline | summary of the assembly buffer 35a. It is a schematic diagram which shows the structure of transmission data. It is a flowchart which shows a reception process. It is explanatory drawing which shows the specific operation | movement by a reception process. It is a flowchart which shows a buffer setting process.

Embodiments according to the present invention will be described below with reference to the drawings.
[Configuration of this embodiment]
FIG. 1 is a block diagram showing a schematic configuration of a communication system 1 to which the present invention is applied.

  The communication system 1 is a vehicle-side device including a DSRC (dedicated narrow area communication) vehicle-mounted device 30 (data receiving device), a navigation device 60, an ignition switch 80, and the like, which is an ETC (registered trademark: Electronic Toll Collection) road machine 10. And data exchange with roadside devices (data transmission devices) such as the DSRC road machine 20 and the like. In the present embodiment, information transmitted from the road machines 10 and 20 to the vehicle is also referred to as service information.

  The ETC roadside device 10 is disposed at a toll gate on a toll road, a parking lot, and the like, and includes an ETC control unit 11 and a toll gate antenna 12. The ETC control unit 11 is configured as a well-known microcomputer having a CPU, ROM, RAM, and the like, and transmits a radio wave from a toll gate antenna 12 to a predetermined area in the toll gate and receives the radio wave (DSRC). When receiving a response from the vehicle-mounted device 30 etc.), the communication is carried out by specifying the communication partner as one vehicle, and the exchange of data (exchange of individual information) such as specifying the communication partner and collecting a charge is performed. To do.

  The ETC control unit 11 is connected to a server (not shown) via a communication line, and causes the server to store information such as a fee collection history and its time in a database in the server.

  The DSRC road machine 20 includes a DSRC control unit 21 and a DSRC antenna 22. The DSRC control unit 21 is configured as a well-known microcomputer including a CPU, ROM, RAM, and the like. Data such as traffic information sent from a data center (not shown) connected in advance via a communication line is used. The loaded radio wave is repeatedly transmitted to a predetermined area including the road (broadcast information exchange). Here, when the DSRC road unit 20 repeatedly transmits a radio wave carrying data such as traffic information, the communication partner is set to an unspecified number of vehicles (the communication partner is specified as one vehicle). do not do).

  The DSRC road machine 20 also performs communication specifying a communication partner as one vehicle. In this case, when receiving a response from a vehicle (DSRC onboard unit 30 or the like) that has received the radio wave, vehicle information ( When information on the travel of the vehicle such as travel history, vehicle speed, and acceleration is requested and desired information is obtained from the vehicle, the information is transmitted to a data center, a server (not shown) or the like and recorded in the transmission destination ( Exchange of individual information). When each road device 10, 20 receives a request to retransmit specific data from the DSRC in-vehicle device 30 when a communication error or the like occurs during exchange of individual information, the function of retransmitting the specific data Have

  The DSRC in-vehicle device 30 receives service information from the roadside devices 10 and 20, performs processing corresponding to the service information (for example, fee settlement processing at a toll gate), and the navigation device 60 of the service information It has a function of transferring what is used in the external device to the external device. In this case, for example, service information including at least one of characters, voice data, and information regarding graphics is transferred from the DSRC on-vehicle device 30 to the navigation device 60, and the navigation device 60 generates an image based on the service information. Then, a process of displaying and displaying a sound and outputting it to the speaker 37 is performed.

  Specifically, the DSRC OBE 30 includes an OBE control unit 31, a radio unit 32, an OBE antenna 33, a communication unit 34, a storage unit 35 (recording unit), a display unit 36, a speaker 37, An input operation unit 38, an IC card control unit 39, and an IC card connector 40 are provided.

  The vehicle-mounted device control unit 31 is configured as a known microcomputer including a CPU, a ROM, a RAM, and the like, and controls the entire DSRC vehicle-mounted device 30. In particular, the in-vehicle device control unit 31 has a function of requesting retransmission of data that could not be received when some data could not be received normally.

  The wireless unit 32 realizes communication between the DSRC vehicle-mounted device 30 and the road devices 10 and 20 by transmitting and receiving radio waves via the vehicle-mounted device antenna 33. That is, the radio unit 32 modulates and transmits a carrier wave having a predetermined frequency in accordance with data received from the in-vehicle device control unit 31 to be transmitted to the road units 10 and 20, and transmits radio waves via the on-vehicle device antenna 33. Upon reception, the received radio wave is demodulated and the obtained data is sent to the vehicle-mounted device control unit 31. The communication unit 34 is configured to be able to communicate with a device such as the navigation device 60 via an in-vehicle LAN 5 (communication line) in which communication is performed using a predetermined protocol such as CAN.

  The storage unit 35 is configured as a well-known writable memory, and the vehicle-mounted device control unit 31 performs writing to and reading from the storage unit 35. In particular, as shown in FIG. 2, the storage unit 35 includes a plurality (n) of assembly buffers 35a, and each assembly buffer 31a is configured to store a plurality of data. . Here, the number of assembly buffers 35a is set to the same number as the maximum number of packets that can be included in one transmission data in accordance with the standards of the ETC roadside device 10 and the DSRC roadside device 20.

  The display unit 36 is configured as a known display, and displays an image corresponding to the image signal from the vehicle-mounted device control unit 31. The input operation unit 38 is configured as an interface for receiving an operation by a user of the system, such as a switch and a keyboard. The operation input through the input operation unit 38 is detected by the vehicle-mounted device control unit 31.

  The IC card control unit 39 reads / writes the IC card 90 set in the IC card connector 40. Specifically, the IC card control unit 39 transmits a command for reading and writing predetermined data to the processing unit 91 of the IC card 90 in response to a command from the vehicle-mounted device control unit 31, and the processing unit that receives this command 91 reads and writes data stored in the storage unit 92 of the IC card 90.

  By such processing, reading / writing of information for specifying the interchange of the used toll road and the parking lot is performed on the IC card 90. Also, from the IC card 90, information for specifying the owner (user) of the IC card 90 and information such as the expiration date of the card are read out.

  The vehicle-mounted device control unit 31 is also connected to an ignition switch 80 in the vehicle, and is configured to detect the state (ON / OFF) of the ignition switch 80. Further, the state of the ignition switch 80 is configured to be detected by the navigation device 60. Further, when receiving a command to transmit probe information (travel history, vehicle speed, acceleration, and other information) from the navigation device 60, the vehicle-mounted device control unit 31 receives the probe information from the navigation device 60 and transmits the probe information on the road. Is transmitted to the machines 10 and 20.

  Note that the navigation device 60 has a function of returning the completion of reception to the DSRC on-board device 30 when receiving data from the DSRC on-vehicle device 30 and a function as a well-known navigation device.

  Here, for example, data having a configuration as shown in FIG. 3 is transmitted and received between the road units 10 and 20 and the DSRC on-vehicle device 30. That is, FIG. 3 shows one frame of data. This data includes FCMC (frame control message channel) including information as a so-called header portion, and a plurality of SCIs (divided data: packets) including actual data (LID portion). ), And CRC which is data for data error check.

  Further, in one frame of data, the FCMC part includes the number of pieces of SCI part as the discrimination information indicating the priority order of information. Here, the discrimination information is recorded in, for example, five levels, and if this level is 3 or more, it is processed as having high priority.

  If the level of the discrimination information is 2 or less, it is processed as a low priority. The LID portion includes data type information (information indicating whether the information is broadcast information or individual information, and whether transfer to the external device is necessary).

  Information on the number of SCI portions is recorded in the FSI portion of the FCMC portion. That is, the number of SCI parts included in one frame can be changed according to the communication specifications. Moreover, real data is divided | segmented into the LID part of several each SCI, and is divided | segmented into several flame | frame as needed.

  When actual data is divided, information for combining the divided data (restoration information: data type, number of divisions, information specifying which part of data) is included in the FCMC part Therefore, the divided data can be restored to the original actual data by referring to the FCMC portion when receiving the data.

[Process of this embodiment]
Processing when the DSRC on-vehicle device 30 receives transmission data transmitted from the road devices 10 and 20 will be described with reference to FIG. FIG. 4 is a flowchart showing a reception process executed by the vehicle-mounted device control unit 31. Note that the processing of S130 to S260 corresponds to the distribution storing means in the present invention.

  The reception process is a process that is started each time the DSRC on-board unit 30 receives transmission data transmitted from the roadside devices 10 and 20, and is executed for each received actual data (LID portion). Process. In the reception process, first, the received data is acquired (S110: reception means).

  Then, it is determined whether or not this data is divided data with reference to the FCMC portion of this data (S120). If it is not divided data (S120: NO), this data is output as usable data (including the case where it is output (recorded) to a memory such as the recording unit 15) (S300), and the data receiving process is terminated.

  If it is divided data (S120: YES), it is determined whether or not this data type has a recorded group number (S130). That is, it is determined whether divided data of the same type is recorded in any assembly buffer 35a.

  If the received data does not have a recorded group number (S130: NO), whether or not the assembly buffer 35a is full (that is, there is no initialized assembly buffer 35a). Determine (S140). If the assembly buffer 35a is not full (S140: NO), data is assembled with a new group number (S150).

  That is, the group number corresponding to this data type is associated with the assembly buffer 35a, and the data is recorded in the assembly buffer 35a. When such processing ends, the data reception processing ends.

  If the assembly buffer 35a is full in the process of S140 (S140), the data in the assembly buffer 35a with the oldest group number (the assembly buffer 35a with the latest update time is the past) is discarded (initialized). In step S210, data is assembled with the new group number in the assembly buffer 35a. When this process ends, the data reception process ends.

  If the received data has a recorded group number in the process of S130 (S130: YES), the data is recorded in the assembly buffer 35a associated with the group number of the received data (S260). ) It is determined with reference to the FCMC portion whether or not all the divided data are prepared in the assembly buffer 35a (S270: Restorability determination unit).

  If all the divided data are prepared (S270: YES), these divided data are combined, and the combined data is output as usable data in the same manner as the processing of S300 (S280: combined output means). Then, the assembly buffer 35a in which the combined divided data has been recorded is initialized (S290: initialization means), and the data reception process ends.

  Next, a specific example of such data reception processing will be described with reference to FIG. In the example shown in FIG. 5, the divided data of type A divided into three and the divided data of types B and C divided into two are included in the transmission data for transmission. In particular, the divided data of a certain type is continuously transmitted, and when the data of this type is completed, the divided data of the next type is continuously transmitted. Such a data transmission method is mainly used when exchanging individual information.

  Specifically, a plurality of types of data are divided, and various types of data are included and transmitted one by one in the transmission data. For example, as shown in FIG. 5, when transmitting divided data of type A divided into three and divided data of types B and C divided into two, the transmission data includes four pieces of divided data. 5 (MDC: equivalent to the above-mentioned SCI), as shown in FIG. 5A, the first divided data (A-1 / 3) of type A, type A in the first frame, as shown in FIG. The second divided data (A-2 / 3), the third divided data of type A (A-3 / 3), and the first divided data of type B (B-1 / 2) are transmitted.

  Then, in the second frame, the second divided data of type B (B-2 / 2), the first divided data of type C (C-1 / 3) are transmitted, and the second divided data of type C Data (C-2 / 3) is transmitted. At this time, as shown in FIG. 5C, divided data is recorded in the assembly buffer 35a for each data type.

  In addition, when some division | segmentation data are not normally received in the DCRC onboard equipment 30, when exchanging individual information, the onboard equipment control part 31 of the DSRC onboard equipment 30 is the roadside machine 10,20. The road unit 10 or 20 transmits the requested data including the requested data in the next frame. Specifically, as shown in FIG. 5B, for example, when the second divided data (A-2 / 3) of type A cannot be normally received, the type A in the next frame is displayed. The second divided data (A-2 / 3) is retransmitted. At this time, in the assembly buffer 35a, as shown in the upper part of FIG. 5C, the first divided data of type A (A-2 / 3) is received until the second divided data of type A (A-2 / 3) is received. A-1 / 3) and the third divided data (A-3 / 3) are held.

[Effect of this embodiment]
In the DSRC on-vehicle device 30 described in detail above, the on-vehicle device control unit 31 receives transmission data transmitted from the ETC roadside device 10 and the DSRC roadside device 20, and each data included in each packet of the received transmission data. Is stored in the storage unit 35 having a plurality of assembly buffers 35a set to the same number as the maximum number of packets that can be included in one transmission data in accordance with the standards of the ETC roadside device 10 and the DSRC roadside device 20. Sort and store by type. And the onboard equipment control part 31 determines based on the restoration information whether or not the divided data is prepared in each assembly buffer 35a in which the data is recorded, and when it is determined that the data is prepared, it is based on the restoration information. Combine the divided data and output.

  According to such a DSRC on-vehicle device 30, the assembly buffer 35a is set to a plurality, and when a part of a certain type of divided data cannot be received normally, another type of divided data is newly received. However, since the newly received divided data can be recorded in the other assembly buffer 35a, the newly received divided data can be received without discarding the previously received divided data. Further, the previously received divided data is held in the assembly buffer 35a, and when the divided data that could not be received is retransmitted, it can be combined (restored) with the original data.

  Furthermore, according to the DSRC on-vehicle device 30, since the upper limit value of the number of assembly buffers 35a is set to the maximum number of packets that can be included in one transmission data, the divided data can be received without providing a useless assembly buffer 35a. Probability can be improved.

  Further, in the DSRC on-vehicle device 30, the on-vehicle device control unit 31 initializes the assembly buffer 35a in which the combined data is recorded, and when receiving a new type of data, takes precedence over the initialized assembly buffer 35a. Data is distributed.

According to such a DSRC on-vehicle device 30, it is possible to make it difficult to delete data before combining.
Furthermore, in the DSRC on-vehicle device 30, the on-vehicle device control unit 31 receives the new type of data, and when there is no assembly buffer 35a that has been initialized, the assembly has not been updated for the longest time. A new type of data is overwritten in the buffer 35a.

According to such a DSRC on-vehicle device 30, it is possible to discard data that has not been combined for a long time.
Further, since the DSRC in-vehicle device 30 is configured as a DSRC wireless communication device, transmission from the ETC roadside device 10 and the DSRC roadside device 20 is possible even when the radio wave condition is temporarily unstable. Data can be received well.

[Other Embodiments]
Embodiments of the present invention are not limited to the above-described embodiments, and can take various forms as long as they belong to the technical scope of the present invention.

  For example, the number of assembly buffers 31a may be dynamically changed by performing the buffer setting process shown in FIG. In addition, FIG. 6 is a flowchart which shows the buffer setting process which the onboard equipment control part 31 performs.

  The buffer setting process is a process that is started each time the DSRC on-vehicle device 30 receives transmission data transmitted from the roadside devices 10 and 20, and is a process that is performed in parallel with the above-described reception process. In the buffer setting process, as shown in FIG. 6, the FSI value in the FCMC part is acquired (S410). Then, the number of assembly buffers 35a (the number of n in FIG. 2) is set to the same number as this value (S420: area number setting means), and the buffer setting process is terminated.

  According to such a DSRC on-vehicle device 30, the number of assembly buffers 35a can be dynamically set by the number of data types that can be transmitted by one transmission data. Therefore, when the number of assembly buffers 35a is set to be small, the unused assembly buffer 35a can be used for other purposes.

  In the above embodiment, the number of assembly buffers 35a is set to a number equal to or less than the maximum number of packets that can be included in one transmission data in accordance with the standards of the ETC roadside device 10 and the DSRC roadside device 20. Good.

  If configured in this way, even if a part of a certain type of divided data could not be received normally, even if another type of divided data was newly received, it was newly received by the other assembly buffer 35a. Since the divided data can be recorded, the newly received divided data can be received without discarding the previously received divided data.

  In the above-described embodiment, as shown in FIG. 5, the configuration has been described in which a certain type of divided data is continuously transmitted, and when this type of data ends, the next type of divided data is continuously transmitted. However, a configuration may be adopted in which a plurality of types of data are divided and various types of data are included and transmitted one by one in the transmission data. For example, as shown in FIG. 5, in the case of transmitting the divided data of type A divided into three and divided data of types B and C divided into two into transmission data, transmission of type A is performed in the first frame. The first divided data (A-1 / 3), the first divided data of type B (B-1 / 2), and the first divided data of type C (C-1 / 3) are transmitted. At the frame, the second divided data of type A (A-2 / 3), the second divided data of type B (B-2 / 2), and the second divided data of type C (C-2 / 3) is transmitted, and the remaining frames may be transmitted sequentially in the third frame.

  Such a transmission method is considered to be effective in the exchange of broadcast information in which the type of data to be transmitted is limited.

  DESCRIPTION OF SYMBOLS 1 ... Communication system, 5 ... In-vehicle LAN, 10 ... ETC roadside machine, 11 ... ETC control part, 12 ... Toll booth antenna, 20 ... DSRC roadside machine, 21 ... DSRC control part, 22 ... DSRC antenna, 30 ... DSRC onboard equipment 30 ... DSRC OBE, 31 ... OBE control unit, 31a ... assembly buffer, 32 ... radio unit, 33 ... onboard unit antenna, 34 ... communication unit, 35 ... storage unit, 35a ... assembly buffer, 36 ... display unit, 37 ... Speaker, 38 ... Input operation unit, 39 ... IC card control unit, 40 ... IC card connector, 60 ... Navigation device, 80 ... Ignition switch, 90 ... IC card, 91 ... Processing unit, 92 ... Storage unit.

Claims (7)

Data to be transmitted is divided into a plurality of packets having a predetermined length, and transmission data including restoration information for restoring the divided data (hereinafter referred to as “divided data”) at a data transmission timing and a predetermined number of packets. A data receiving device capable of receiving transmission data transmitted from at least a part of the transmission data,
Receiving means for receiving transmission data transmitted from the data transmitting device;
Each data included in each packet of the received transmission data has a plurality of recording areas set to a number equal to or less than the maximum number of packets that can be included in one transmission data according to the standard of the data transmission apparatus. A distribution storage means for distributing and storing each type of data in the recording unit;
In each recording area where data is recorded by the distribution storage means, restoration possibility determination means for determining whether divided data is prepared based on the restoration information;
Combined output means for combining and outputting divided data based on the restoration information when it is determined by the restoration possibility judging means that the data is prepared;
A data receiving apparatus comprising: The data receiving device according to claim 1,
Initializing means for initializing a recording area in which the combined data was recorded,
The distribution storage means, when receiving a new type of data, preferentially distributes the data to the initialized recording area. The data receiving device according to claim 2,
If there is no recording area that is initialized when a new type of data is received, the distribution storage means stores the new type of data in the recording area that has not been updated for the longest time. A data receiving device characterized by overwriting. In the data receiver of any one of Claims 1-3,
The distribution storage unit is provided for each data type with respect to a recording unit having a plurality of recording areas set to the same number as the maximum number of packets that can be included in one transmission data according to the standard of the data transmission device. A data receiving device characterized by being sorted and stored. In the data receiver of any one of Claims 1-3,
When the transmission data includes information on the number of packets included in the transmission data, an area number setting unit that sets the number of recording areas to the same number as the number of packets;
A data receiving apparatus comprising: In the data receiver of any one of Claims 1-5,
The data receiving device is configured as a DSRC wireless communication device.   A data receiving program for causing a computer to function as each means constituting the data receiving apparatus according to any one of claims 1 to 6.

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