JP2014049912A - Terminal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a terminal device capable of efficiently processing data for each of plural kinds of applications.SOLUTION: An input section 110 sequentially inputs data which are classified to any of plural prescribed transmission priorities. A classification section 112 classifies the data according to the priority of the data. An extraction section 122 extracts the input and classified data preferentially from the data having a higher transmission priority and packs the data in a packet signal to be transmitted in a period when inter-terminal communication is possible.

Description

  The present invention relates to communication technology, and more particularly to a terminal device that broadcasts a signal including predetermined information.

  It is desirable to schedule transmissions efficiently in a wireless network. For example, if each flow is associated with a request such as throughput and delay, the communication interval for each flow is determined based on the request for the flow (see, for example, Patent Document 1).

Special table 2008-502211 gazette

  Data to be communicated may occur in bursts. Thus, it is desirable to efficiently handle data generated in a burst manner.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a technique for efficiently processing data for each of a plurality of types of applications.

  In order to solve the above problems, a terminal device according to an aspect of the present invention includes an input unit that sequentially inputs data corresponding to one of a plurality of prescribed transmission priorities, and data that is sequentially input at the input unit A control unit that stores data in a packet signal to be transmitted in a period in which inter-terminal communication is possible with priority from data having a high transmission priority.

  It should be noted that any combination of the above-described constituent elements and a conversion of the expression of the present invention between a method, an apparatus, a system, a recording medium, a computer program, etc. are also effective as an aspect of the present invention.

  According to the present invention, data for each of a plurality of types of applications can be efficiently processed.

It is a figure which shows the structure of the communication system which concerns on Example 1 of this invention. It is a figure which shows the structure of the base station apparatus of FIG. FIGS. 3A to 3D are diagrams showing frame formats defined in the communication system of FIG. It is a figure which shows the structure of the terminal device mounted in the vehicle of FIG. It is a figure which shows the protocol stack in the terminal device of FIG. It is a figure which shows the structure of the application management part of FIG. It is a figure which shows the data structure of the table memorize | stored in the classification | category part of FIG. FIGS. 8A to 8C are diagrams illustrating an outline of processing in the application management unit in FIG. It is a figure which shows the example of timing allocation by the application management part of FIG. It is a figure which shows the format of the packet signal produced | generated by the terminal device of FIG. It is a flowchart which shows the storage procedure of the data by the application management part of FIG. 7 is a flowchart showing a data discarding procedure by the application management unit of FIG. 6. It is a figure which shows the data structure of the table memorize | stored in the classification | category part which concerns on Example 2 of this invention. It is a figure which shows the structure of the communication system which concerns on Example 3 of this invention. It is a figure which shows the structure of the terminal device of FIG. It is a figure which shows the structure of the portable radio | wireless apparatus of FIG.

Example 1
Prior to specific description of the first embodiment of the present invention, the basic knowledge will be described. Embodiment 1 of the present invention relates to a communication system that executes vehicle-to-vehicle communication between terminal devices mounted on a vehicle and also executes road-to-vehicle communication from a base station device installed at an intersection or the like to a terminal device. Such a communication system is also called ITS (Intelligent Transport Systems). ITS is stipulated in, for example, a standard for a 700 MHz band intelligent transportation system (Radio Industry Association). The communication system uses an access control function called CSMA / CA (Carrier Sense Multiple Access Collision Aviation), as well as a wireless LAN (Local Area Network) compliant with a standard such as IEEE 802.11. Therefore, the same radio channel is shared by a plurality of terminal devices. On the other hand, in ITS, it is necessary to transmit information to an unspecified number of terminal devices. In order to efficiently perform such transmission, the communication system broadcasts a packet signal.

  That is, as inter-vehicle communication, the terminal device broadcasts a packet signal that stores information such as the speed or position of the vehicle. In addition, the other terminal device receives the packet signal and recognizes the approach of the vehicle based on the above-described information. Here, in order to reduce interference between road-vehicle communication and vehicle-to-vehicle communication, the base station apparatus repeatedly defines a frame including a plurality of subframes. The base station apparatus selects any of a plurality of subframes for road-to-vehicle communication, and broadcasts a packet signal in which control information and the like are stored during the period of the head portion of the selected subframe.

  The control information includes information related to a period for the base station apparatus to broadcast the packet signal (hereinafter referred to as “road vehicle transmission period”). The terminal device specifies a road and vehicle transmission period based on the control information, and broadcasts a packet signal by the CSMA method in a period other than the road and vehicle transmission period (hereinafter referred to as “vehicle transmission period”). As a result, road-to-vehicle communication and vehicle-to-vehicle communication are time-division multiplexed. Note that a terminal device that cannot receive control information from the base station device, that is, a terminal device that exists outside the area formed by the base station device transmits a packet signal by the CSMA method regardless of the frame configuration.

  Next, an outline of the present embodiment will be described. It is desirable for the terminal device to efficiently process a plurality of types of applications, particularly applications that generate data in bursts. In order to cope with this, in the communication system, the priority of transmission for each application is determined in advance. The terminal device accumulates input data for each priority, and generates a packet signal while preferentially extracting application data having a high priority. Since the band is not secured in advance in this way, data generated in a burst manner is efficiently stored in the packet signal.

  FIG. 1 shows a configuration of a communication system 100 according to Embodiment 1 of the present invention. This corresponds to a case where one intersection is viewed from above. The communication system 100 includes a base station device 10, a first vehicle 12a, a second vehicle 12b, a third vehicle 12c, a fourth vehicle 12d, a fifth vehicle 12e, a sixth vehicle 12f, and a seventh vehicle 12g, collectively referred to as a vehicle 12. , The eighth vehicle 12h, and the network 202. Here, only the first vehicle 12 a is shown, but each vehicle 12 is equipped with a terminal device 14. An area 212 is formed around the base station apparatus 10, and an outside area 214 is formed outside the area 212.

  As shown in the drawing, the road that goes in the horizontal direction of the drawing, that is, the left and right direction, intersects the vertical direction of the drawing, that is, the road that goes in the up and down direction, at the central portion. Here, the upper side of the drawing corresponds to the direction “north”, the left side corresponds to the direction “west”, the lower side corresponds to the direction “south”, and the right side corresponds to the direction “east”. The intersection of the two roads is an “intersection”. The first vehicle 12a and the second vehicle 12b are traveling from left to right, and the third vehicle 12c and the fourth vehicle 12d are traveling from right to left. Further, the fifth vehicle 12e and the sixth vehicle 12f are traveling from the top to the bottom, and the seventh vehicle 12g and the eighth vehicle 12h are traveling from the bottom to the top.

  In the communication system 100, the base station apparatus 10 is fixedly installed at an intersection. The base station device 10 controls communication between terminal devices. The base station apparatus 10 receives a frame including a plurality of subframes based on a signal received from a GPS (Global Positioning System) satellite (not shown) or a frame formed by another base station apparatus 10 (not shown). Generate repeatedly. Here, the road vehicle transmission period can be set at the head of each subframe.

  The base station apparatus 10 selects a subframe in which the road and vehicle transmission period is not set by another base station apparatus 10 from among a plurality of subframes in the frame. The base station apparatus 10 sets a road and vehicle transmission period at the beginning of the selected subframe. The base station apparatus 10 notifies the packet signal in the set road and vehicle transmission period. In the road and vehicle transmission period, a plurality of packet signals may be notified. The packet signal includes, for example, accident information, traffic jam information, signal information, and the like. Note that the packet signal also includes information related to the timing when the road and vehicle transmission period is set and control information related to the frame.

  As described above, the terminal device 14 is mounted on the vehicle 12 and is movable. When receiving the packet signal from the base station apparatus 10, the terminal apparatus 14 estimates that the terminal apparatus 14 exists in the area 212. When the terminal device 14 exists in the area 212, the terminal device 14 generates a frame based on the control information included in the packet signal, in particular, the information on the timing when the road and vehicle transmission period is set and the information on the frame. As a result, the frame generated in each of the plurality of terminal devices 14 is synchronized with the frame generated in the base station device 10. The terminal device 14 notifies the packet signal in the vehicle transmission period that is a period different from the road and vehicle transmission period. Here, CSMA / CA is executed in the vehicle transmission period. On the other hand, when it is estimated that the terminal apparatus 14 exists outside the area 214, the terminal apparatus 14 notifies the packet signal by executing CSMA / CA regardless of the frame configuration.

  FIG. 2 shows the configuration of the base station apparatus 10. The base station apparatus 10 includes an antenna 20, an RF unit 22, a modem unit 24, a processing unit 26, a control unit 28, and a network communication unit 30. Further, the processing unit 26 includes a frame defining unit 32, a selecting unit 34, and a generating unit 36.

  The RF unit 22 receives a packet signal from a terminal device 14 (not shown) or another base station device 10 by the antenna 20 as a reception process. The RF unit 22 performs frequency conversion on the received radio frequency packet signal to generate a baseband packet signal. Further, the RF unit 22 outputs a baseband packet signal to the modem unit 24. In general, baseband packet signals are formed by in-phase and quadrature components, so two signal lines should be shown, but here only one signal line is shown for clarity. Shall be shown. The RF unit 22 includes an LNA (Low Noise Amplifier), a mixer, an AGC, and an A / D conversion unit.

  As a transmission process, the RF unit 22 performs frequency conversion on the baseband packet signal input from the modem unit 24 to generate a radio frequency packet signal. Further, the RF unit 22 transmits a radio frequency packet signal from the antenna 20 during the road-vehicle transmission period. The RF unit 22 also includes a PA (Power Amplifier), a mixer, and a D / A conversion unit. For example, the 700 MHz band is used as the radio frequency.

  The modem unit 24 demodulates the baseband packet signal from the RF unit 22 as a reception process. Further, the modem unit 24 outputs the demodulated result to the processing unit 26. The modem unit 24 also modulates the data from the processing unit 26 as a transmission process. Further, the modem unit 24 outputs the modulated result to the RF unit 22 as a baseband packet signal. Here, since the communication system 100 corresponds to an OFDM (Orthogonal Frequency Division Multiplexing) modulation scheme, the modem unit 24 also performs FFT (Fast Fourier Transform) as reception processing and IFFT (Inverse Fast Trans) as transmission processing. Also execute.

  The frame defining unit 32 receives a signal from a GPS satellite (not shown), and acquires time information based on the received signal. In addition, since a well-known technique should just be used for acquisition of the information of time, description is abbreviate | omitted here. The frame defining unit 32 generates a plurality of frames based on the time information. For example, the frame defining unit 32 generates ten “100 msec” frames by dividing the “1 sec” period into ten on the basis of the timing indicated by the time information. By repeating such processing, the frame is defined to be repeated. The frame defining unit 32 may detect control information from the demodulation result and generate a frame based on the detected control information. Such processing corresponds to generating a frame synchronized with the timing of the frame formed by another base station apparatus 10.

  3A to 3D show frame formats defined in the communication system 100. FIG. FIG. 3A shows the structure of the frame. The frame is formed of N subframes indicated as the first subframe to the Nth subframe. This can be said that the terminal device 14 forms a frame by multiplexing a plurality of subframes that can be used for notification for a plurality of hours. For example, when the frame length is 100 msec and N is 8, a subframe having a length of 12.5 msec is defined. N may be other than 8. The description of FIGS. 3B to 3D will be described later and returns to FIG.

  The selection part 34 selects the sub-frame which should set a road and vehicle transmission period among several sub-frames contained in the flame | frame. More specifically, the selection unit 34 receives a frame defined by the frame defining unit 32. The selection unit 34 receives an instruction regarding the selected subframe via an interface (not shown). The selection unit 34 selects a subframe corresponding to the instruction. Apart from this, the selection unit 34 may automatically select a subframe. At this time, the selection unit 34 inputs a demodulation result from another base station device 10 or the terminal device 14 (not shown) via the RF unit 22 and the modem unit 24. The selection part 34 extracts the demodulation result from the other base station apparatus 10 among the input demodulation results. The selection unit 34 specifies the subframe that has not received the demodulation result by specifying the subframe that has received the demodulation result.

  This corresponds to specifying a subframe in which the road and vehicle transmission period is not set by another base station apparatus 10, that is, an unused subframe. When there are a plurality of unused subframes, the selection unit 34 selects one subframe at random. When there are no unused subframes, that is, when each of a plurality of subframes is used, the selection unit 34 acquires reception power corresponding to the demodulation result, and gives priority to subframes with low reception power. Select

  FIG. 3B shows a configuration of a frame generated by the first base station apparatus 10a. The first base station apparatus 10a sets a road and vehicle transmission period at the beginning of the first subframe. Moreover, the 1st base station apparatus 10a sets a vehicle transmission period following the road and vehicle transmission period in a 1st sub-frame. The vehicle transmission period is a period during which the terminal device 14 can notify the packet signal. That is, the first base station apparatus 10a can notify the packet signal in the road and vehicle transmission period which is the first period of the first subframe, and the terminal apparatus in the vehicle and vehicle transmission period other than the road and vehicle transmission period in the frame. It is specified that 14 can broadcast the packet signal. Furthermore, the first base station apparatus 10a sets only the vehicle transmission period from the second subframe to the Nth subframe.

  FIG. 3C shows a configuration of a frame generated by the second base station apparatus 10b. The second base station apparatus 10b sets a road and vehicle transmission period at the beginning of the second subframe. Also, the second base station apparatus 10b sets the vehicle transmission period from the first stage of the road and vehicle transmission period in the second subframe, from the first subframe and the third subframe to the Nth subframe. FIG. 3D shows a configuration of a frame generated by the third base station apparatus 10c. The third base station apparatus 10c sets a road and vehicle transmission period at the beginning of the third subframe. In addition, the third base station apparatus 10c sets the vehicle transmission period from the first stage of the road and vehicle transmission period in the third subframe, the first subframe, the second subframe, and the fourth subframe to the Nth subframe. As described above, the plurality of base station apparatuses 10 select different subframes, and set the road and vehicle transmission period at the head portion of the selected subframe. Returning to FIG. The selection unit 34 outputs the selected subframe number to the generation unit 36.

  The generation unit 36 receives a subframe number from the selection unit 34. The generation unit 36 sets a road and vehicle transmission period in the subframe of the received subframe number, and generates a packet signal to be notified during the road and vehicle transmission period. When a plurality of packet signals are transmitted in one road and vehicle transmission period, the generation unit 36 generates them. The packet signal is composed of control information and a payload. The control information includes a subframe number in which a road and vehicle transmission period is set. The payload includes, for example, accident information, traffic jam information, signal information, and the like. These data are acquired from the network 202 (not shown) by the network communication unit 30. The processing unit 26 broadcasts the packet signal to the modem unit 24 and the RF unit 22 during the road and vehicle transmission period. The control unit 28 controls processing of the entire base station device 10.

  This configuration can be realized in terms of hardware by a CPU, memory, or other LSI of any computer, and in terms of software, it can be realized by a program loaded in the memory, but here it is realized by their cooperation. Draw functional blocks. Accordingly, those skilled in the art will understand that these functional blocks can be realized in various forms only by hardware, or by a combination of hardware and software.

  FIG. 4 shows the configuration of the terminal device 14 mounted on the vehicle 12. The terminal device 14 includes an antenna 50, an RF unit 52, a modem unit 54, a processing unit 56, and a control unit 58. The processing unit 56 includes a timing specifying unit 60, a transfer determination unit 62, an acquisition unit 64, a generation unit 66, a user IF unit 68, a notification unit 70, an application processing unit 76, and an application management unit 78. The timing specifying unit 60 includes an extraction unit 72 and a carrier sense unit 74. The antenna 50, the RF unit 52, and the modem unit 54 execute the same processing as the antenna 20, the RF unit 22, and the modem unit 24 in FIG. Here, the difference will be mainly described.

  The modem unit 54 and the processing unit 56 receive a packet signal from another terminal device 14 or the base station device 10 (not shown) in the reception process. As described above, the modem unit 54 and the processing unit 56 receive a packet signal from the base station apparatus 10 during the road-to-vehicle transmission period, and receive packet signals from other terminal apparatuses 14 during the vehicle-to-vehicle transmission period. To do.

  When the demodulation result from the modem unit 54 is a packet signal from the base station apparatus 10 (not shown), the extraction unit 72 specifies the timing of the subframe in which the road and vehicle transmission period is arranged. In that case, the extraction part 72 estimates that it exists in the area 212 of FIG. The extraction unit 72 generates a frame based on the subframe timing and the content of the message header of the packet signal. As a result, the extraction unit 72 generates a frame synchronized with the frame formed in the base station device 10. When the notification source of the packet signal is another terminal device 14, the extraction unit 72 omits the synchronized frame generation process. If the extraction unit 72 exists in the area 212, the extraction unit 72 specifies the remaining vehicle transmission period after specifying the road and vehicle transmission period in use. The extraction unit 72 outputs information on frame and subframe timing and vehicle transmission period to the carrier sense unit 74.

  On the other hand, when the extraction unit 72 does not receive a packet signal from the base station apparatus 10, that is, when a frame synchronized with the base station apparatus 10 is not generated, the extraction unit 72 estimates that the extraction unit 72 exists outside the area 214 in FIG. When the extraction unit 72 exists outside the area 214, the extraction unit 72 selects a timing unrelated to the frame configuration, and instructs the carrier sense unit 74 to execute carrier sense unrelated to the frame configuration.

  The carrier sense unit 74 receives information about the timing of the frames and subframes and the vehicle transmission period from the extraction unit 72. The carrier sense unit 74 determines the transmission timing by starting CSMA / CA within the vehicle transmission period. This is equivalent to setting NAV (Network Allocation Vector) for the road and vehicle transmission period and performing carrier sense outside the period in which NAV is set. On the other hand, when the carrier sense unit 74 is instructed by the extraction unit 72 to execute carrier sense not related to the frame configuration, the carrier sense unit 74 performs transmission timing by executing CSMA / CA without considering the frame configuration. To decide. The carrier sense unit 74 notifies the modem unit 54 and the RF unit 52 of the determined transmission timing, and broadcasts the packet signal.

  The transfer determination unit 62 controls transfer of control information. The transfer determination unit 62 extracts information to be transferred from the control information. The transfer determination unit 62 generates information to be transferred based on the extracted information. Here, the description of this process is omitted. The transfer determination unit 62 outputs information to be transferred, that is, a part of the control information, to the generation unit 66. The generation unit 66 receives data from the application management unit 78 and receives a part of control information from the transfer determination unit 62. Data received from the application management unit 78 will be described later. The generating unit 66 generates a packet signal by storing a part of the received control information in the control information and storing data in the payload. The processing unit 56, the modem unit 54, and the RF unit 52 sequentially notify the plurality of packet signals generated by the generating unit 66. The control unit 58 controls the operation of the terminal device 14.

  The acquisition unit 64 includes a GPS receiver (not shown), a gyroscope, a vehicle speed sensor, and the like. Based on data supplied from these, the location of the vehicle 12 (not shown), that is, the position of the vehicle 12 on which the terminal device 14 is mounted, the progress The direction, the moving speed, etc. (hereinafter collectively referred to as “position information”) are acquired. The existence position is indicated by latitude and longitude. Since a known technique may be used for these acquisitions, description thereof is omitted here. The GPS receiver, gyroscope, vehicle speed sensor, and the like may be outside the terminal device 14. The acquisition unit 64 outputs the position information to the application processing unit 76.

  The application processing unit 76 can execute a plurality of types of applications. Each application is executed between the plurality of terminal devices 14. That is, the transmission-side terminal device 14 generates data and broadcasts the packet signal in which the data is stored, and the reception-side terminal device 14 receives the packet signal and stores the data included in the packet signal. And a predetermined process is executed. Therefore, one application is divided into processing on the transmission side (hereinafter referred to as “transmission-side application”) and processing on the reception side (hereinafter referred to as “reception-side application”). Here, the transmission-side application and the reception-side application that are executed in one terminal device 14 need not match. Hereinafter, the transmission side application and the reception side application may be collectively referred to as an application.

  Multiple types of applications are classified as follows. The first is a common application. The common application is an application for warning the driver of the approach of another vehicle 12 and is executed in all the terminal devices 14. The application processing unit 76 inputs position information from the acquisition unit 64 when executing the transmission side application in the common application. In addition, the application processing unit 76 periodically outputs position information to the application management unit 78.

  On the other hand, the application processing unit 76 acquires the position information included in the packet signal from the other terminal device 14 from the application management unit 78 as a receiving-side application in the common application. The application processing unit 76 detects the approach of the other vehicle 12 based on the position information of the other terminal device 14 acquired from the application management unit 78 and the position information input from the acquisition unit 64. The application processing unit 76 causes the notification unit 70 to notify the approach of another vehicle 12. The notification unit 70 performs notification to the driver via a monitor or a speaker. The second is a free application. The free application is executed only on an arbitrary terminal device 14 instead of all terminal devices 14. Multiple free applications may be executed simultaneously.

  Under the situation where the above-mentioned regulations are made, the application processing unit 76 outputs the generated data to the application management unit 78 when executing the transmission-side application in the free application permitted to be registered. On the other hand, when executing the receiving side application, the application processing unit 76 executes processing corresponding to the free application on the data received from the application management unit 78.

  The application management unit 78 receives an application registration request from the user IF unit 68 in advance as processing for the transmission side application. Next, the application management unit 78 receives a plurality of data from the application processing unit 76, and generates a plurality of data that is a target of packet signal generation in order to generate a packet signal based on the plurality of data. 66. A specific example of data output processing by the application management unit 78 will be described later.

  On the other hand, the application management unit 78 accepts data stored in the packet signal received by the extraction unit 72 as processing for the receiving-side application. Of the received data, the application management unit 78 outputs data corresponding to the reception-side application being executed in the application processing unit 76 to the application processing unit 76. The application management unit 78 discards other data.

  In summary, in the communication system 100, both the base station apparatus 10 and the terminal apparatus 14 perform communication at a cycle of about 100 ms. Further, in order to reduce interference between road-to-vehicle communication and vehicle-to-vehicle communication, road-to-vehicle communication and vehicle-to-vehicle communication are time-division multiplexed. In order to secure the road-to-vehicle transmission period, the base station apparatus 10 includes the transmission time and road-to-vehicle communication period information in the packet signal and notifies the surrounding terminal devices. The terminal device 14 in the area 212 synchronizes time based on the transmission time received from the base station device 10 and stops transmission based on road-to-vehicle communication period information, thereby timing CSMA / CA at a timing other than the road-vehicle transmission period. The packet signal is transmitted at. The inter-vehicle communication payload is composed of common application data and free application data.

  Hereinafter, the processing in the application processing unit 76 and the application management unit 78 will be specifically described. First, in order to explain the overall process for a plurality of applications, a protocol stack related to the application processing unit 76 and the application management unit 78 is used. FIG. 5 shows a protocol stack in the terminal device 14. Since the application processing unit 76 and the application management unit 78 in the two stages from the top are included in the terminal device 14 on the transmission side, processing for the transmission-side application is executed. Since the application management unit 78 and the application processing unit 76 in the two tiers from the bottom are included in the terminal device 14 on the receiving side, processing for the receiving application is executed. The transmission side application processing unit 76 executes a plurality of types of applications. Here, it is assumed that they are a common application, a first free application, a second free application, and a third free application. The application processing unit 76 outputs data corresponding to each application to the application management unit 78.

  The application management unit 78 manages the application activated in the application processing unit 76. Further, the application management unit 78 on the transmission side accepts a plurality of data from the application processing unit 76 and aggregates the plurality of data in order to store them in one packet signal. A packet signal obtained by aggregating a plurality of data is output from the application management unit 78.

  The receiving-side application management unit 78 inputs a packet signal obtained by collecting a plurality of data. The application management unit 78 extracts data for the common application included in the packet signal and outputs the data to the application processing unit 76. In addition, the application management unit 78 manages the free application activated in the subsequent application processing unit 76, and extracts data corresponding to the activated free application. At that time, data is extracted based on the application ID included in the free application header. The application management unit 78 outputs the extracted data to the application processing unit 76. On the other hand, the application management unit 78 discards the remaining data. For example, since the third free application is not executed in the application processing unit 76 at the subsequent stage, the application management unit 78 discards the data of the third free application. The application processing unit 76 receives data from the application management unit 78 and executes an application corresponding to the data. Here, it is assumed that they are a common application, a first free application, a second free application, and a fourth free application.

  FIG. 6 shows the configuration of the application management unit 78. The application management unit 78 includes an input unit 110, a classification unit 112, a common application data storage unit 114, a high priority application data storage unit 116, a medium priority application data storage unit 118, and a low priority application data storage unit. 120 and an extraction unit 122. This corresponds to a configuration for processing the transmission-side application in the application management unit 78.

  The input unit 110 sequentially inputs data from the application processing unit 76. The input data is output from each of a plurality of applications operating in the application processing unit 76. Here, the plurality of applications include a common application and at least one free application. For the sake of clarity, it is assumed that the free applications are four types of applications from the first free application to the fourth free application.

  Each data is given identification information (hereinafter referred to as “application ID”) for specifying an application, and a transmission expiration date. Since the common application is intended to prevent collision accidents of the vehicle 12 or the like, a periodic output is required for the data. Therefore, the common application data is periodically input to the input unit 110. On the other hand, data of a plurality of free applications is generated in a burst manner. Note that free application data may be generated periodically. The input unit 110 outputs the sequentially input data to the classification unit 112.

  The classification unit 112 receives an application registration request via the user IF unit 68 before inputting data from the input unit 110. The application registration request is a request for registering an application corresponding to data to be transmitted from the terminal device 14. Since the common application is an essential application, it is registered even if no application registration request is made. Therefore, it is assumed that the application registration request here is a request for a free application. At the time of application registration request, one of a plurality of prescribed transmission priorities is registered. When the transmission priority is high, data is easily transmitted, and when the transmission priority is low, data is difficult to be transmitted. As an example, “high”, “medium”, and “low” are defined as transmission priorities.

  FIG. 7 is a diagram illustrating a data structure of a table stored in the classification unit 112. As illustrated, the first free application is registered with a priority “high”, the second free application is registered with a priority “medium”, and the third free application and the fourth free application are registered with a priority “low”. Returning to FIG. Since there are not many types of free applications that periodically output data, it is generally considered that many free applications output data in bursts. Therefore, the application management unit 78 does not negotiate whether or not to accept the application depending on the data size, and the free application is registered together with the transmission priority assigned in advance by the operator or the like. As a response to the application registration request, the classification unit 112 may return the maximum data communication speed.

  After such registration, the classification unit 112 inputs data from the input unit 110. Such data can be said to be data corresponding to any of a plurality of prescribed transmission priorities and data from a free application. Further, the data includes data to be transmitted periodically regardless of the transmission priority, and data from a common application. The classification unit 112 classifies the input data while referring to the table of FIG. More specifically, the classification unit 112 outputs the common application data to the common application data storage unit 114. The classification unit 112 outputs the data of the free application having the priority “high” to the data storage unit 116 for the high priority application, and the data of the free application having the priority “medium” to the data storage unit 118 for the medium priority application. The data of the free application having the priority “low” is output to the data storage unit 120 for the low priority application.

  The common application data storage unit 114 inputs data and stores the data until it is extracted from the extraction unit 122. That is, the common application data storage unit 114 is a FIFO (First-In First-Out) type memory. The high priority application data storage unit 116, the medium priority application data storage unit 118, and the low priority application data storage unit 120 operate in the same manner as the common application data storage unit 114. The common application data storage unit 114, the high priority application data storage unit 116, the medium priority application data storage unit 118, and the low priority application data storage unit 120 may have different storage amounts. .

  The extraction unit 122 extracts data from each of the common application data storage unit 114, the high priority application data storage unit 116, the medium priority application data storage unit 118, and the low priority application data storage unit 120, The extracted data is output to the generation unit 66. The production | generation part 66 stores data in the packet signal which should be transmitted in a vehicle transmission period. The extraction unit 122 extracts data from the common application data storage unit 114 according to a cycle defined in the common application, and outputs the data to the generation unit 66. When the period defined in the common application is equal to the frame interval, the extraction unit 122 extracts the data from the common application data storage unit 114 each time. On the other hand, when the period defined in the common application is longer than the frame interval, the extraction unit 122 may not extract data from the common application data storage unit 114.

  The extraction unit 122 extracts data from the high priority application data storage unit 116, the medium priority application data storage unit 118, and the low priority application data storage unit 120 according to the transmission priority. That is, after storing the packet signal for the common application data, if the packet signal can further store the data, the extraction unit 122 preferentially extracts the data with high transmission priority.

  Specifically, when the data can be stored in the packet signal, the extraction unit 122 extracts the data from the high-priority application data storage unit 116. If there is no data to be extracted from the high priority application data storage unit 116 and the data can be stored in the packet signal, the extraction unit 122 extracts the data from the medium priority application data storage unit 118. When there is no data to be extracted from the medium priority application data storage unit 118 and the data can be stored in the packet signal, the extraction unit 122 extracts the data from the low priority application data storage unit 120. Here, when extracting the data, the extraction unit 122 may discard data that has exceeded the transmission expiration date among data not stored in the packet signal.

  FIGS. 8A to 8C show an outline of processing in the application management unit 78. FIG. Here, for the sake of clarity, only the processing for the free application data will be described, and the description of the processing for the common application data will be omitted. FIG. 8A shows data stored in the high-priority application data storage unit 116, the medium-priority application data storage unit 118, and the low-priority application data storage unit 120. The high priority application data storage unit 116 stores “high-1” data, and the medium priority application data storage unit 118 stores “medium−1”, “medium-2”, “medium−”. 3 ”is stored, and the low priority application data storage unit 120 stores“ low −1 ”and“ low −2 ”data. Here, the data is stored in the order of “middle-1”, “middle-2”, “middle-3”, and also in the order of “low-1” and “low-2”. The extraction unit 122 extracts “high-1” according to the priority, and stores this in the packet signal. Since further data can be stored in the packet signal, the extraction unit 122 extracts “medium −1” and stores it in the packet signal.

  FIG. 8B shows processing at the timing following FIG. As a result of the processing shown in FIG. 8A, no data is stored in the high priority application data storage unit 116, and “medium-2” and “medium−” are stored in the medium priority application data storage unit 118. 3 "is stored. The extraction unit 122 extracts “medium-2” and “medium-3” according to the priority, and stores them in the packet signal. FIG. 8C shows processing at the timing following FIG. 8B. The high priority application data storage unit 116 stores new data “high-2”. On the other hand, no data is stored in the medium priority application data storage unit 118 as a result of the processing shown in FIG. The extraction unit 122 extracts “high-2” according to the priority, and stores these in the packet signal. Data can be further stored in the packet signal, but “low −1” exceeds the transmission expiration date, so the extraction unit 122 discards it. The extraction unit 122 extracts “low-2” and stores it in the packet signal.

  FIG. 9 shows an example of timing allocation by the application management unit 78. As a premise, it is assumed that the terminal device 14 broadcasts one packet signal in a 100 msec frame. Further, the transmission interval of the common application is defined as “100 msec”. Furthermore, the transmission priority for the free application is defined as shown in FIG. In the first packet signal to the third packet signal, common application data is preferentially assigned. In the first packet signal, data of the second free application is assigned in addition to the data of the first free application. In the second packet signal, data of two second free applications are also allocated. In the third packet signal, the data of the third free application is assigned in addition to the data of the first free application input after the generation of the second packet signal.

  FIG. 10 shows a format of a packet signal generated by the terminal device 14. This is the format of the packet signal output from the application management unit 78, and is stored in the payload in the generation unit 66. In order from the top, an application header, a common area, and a free area are arranged. The common area is an area used for a common application, in which common application data is stored. The free area is an area used for a free application, and is divided into a free application header and free application data. The free application header includes control information for each free application in addition to information on the number of applications. The control information for the free application includes an application ID and a data size. Here, the data size relates to data of a free application described later. The free application data includes data of each free application. Note that the number of free applications included in the free area is not limited to two.

  In FIG. 10, the header for the first free application, the header for the second free application, the data for the first free application, and the data for the second free application are arranged in this order. However, the header for the first free application, the data for the first free application, the header for the second free application, and the data for the second free application may be arranged in this order. That is, the header and data for one free application may be continuously arranged.

  The operation of the communication system 100 configured as above will be described. FIG. 11 is a flowchart showing a data storage procedure by the application management unit 78. For each step, for example, step 10 is expressed as S10. If data can be stored in the packet signal (Y in S10) and there is data for common application (Y in S12), the application management unit 78 stores the data for common application in the packet signal (S14). Return to. If there is no common application data (N in S12) and there is high priority data (Y in S16), the application management unit 78 stores the high priority data in the packet signal (S18), and proceeds to Step 10. Return.

  If there is no high-priority data (N in S16) and medium-priority data is present (Y in S20), the application management unit 78 stores the medium-priority data in the packet signal (S22). Return to. If there is no medium priority data (N in S20) and there is low priority data (Y in S24), the application management unit 78 stores the low priority data in the packet signal (S26), and the processing is performed. Is terminated. If data cannot be stored in the packet signal (N in S10), or if there is no low priority data (N in S24), the process is terminated.

  FIG. 12 is a flowchart showing a data discarding procedure by the application management unit 78. If the data exceeds the transmission expiration date (Y in S30), the application management unit 78 discards the data (S32). If the data does not exceed the transmission expiration date (N in S30), the process is terminated.

  According to the embodiment of the present invention, data that has been registered in advance is preferentially stored in the packet signal from data having a high transmission priority, so that the transmission frequency of data having a high transmission priority can be increased. In addition, since the transmission frequency of data with high transmission priority increases, even if the transmission opportunity is limited to the vehicle transmission period, it is possible to suppress the reduction of the transmission opportunity. Moreover, since the transmission opportunity according to the priority of transmission is implement | achieved, even if a transmission opportunity is limited to a vehicle transmission period, a data process can be performed efficiently. Moreover, since data exceeding the transmission expiration date is discarded, transmission of unnecessary data can be suppressed. As a result, it is possible to suppress the deterioration of frequency utilization efficiency. In addition, since the data of the common application is periodically transmitted regardless of the transmission priority, the periodicity of the data of the common application can be maintained.

(Example 2)
As in the first embodiment, the second embodiment relates to a communication system in which vehicle-to-vehicle communication is performed and road-to-vehicle communication is also performed. Similarly to the first embodiment, the terminal device according to the second embodiment stores free application data in a packet signal based on the transmission priority. Here, also in the second embodiment, a transmission expiration date is set for each data. When the total size of untransmitted data becomes larger than the threshold value, the terminal device excludes data with low transmission priority from transmission targets. The communication system 100, the base station apparatus 10, and the terminal apparatus 14 according to the second embodiment are the same types as those in FIGS. 1, 2, and 4, and here, differences will be mainly described.

  In the application management unit 78 of FIG. 6, the classification unit 112 includes a common application data storage unit 114, a high priority application data storage unit 116, a medium priority application data storage unit 118, and a low priority application data storage unit. The total amount of data stored in 120 is measured. This can be said to be the size of data to be processed by the application management unit 78. Further, when measuring the total amount, the measurement may be limited to data within the transmission expiration date. On the other hand, the classification unit 112 stores a threshold value in advance, and compares the total amount of data with the threshold value.

  FIG. 13 shows a data structure of a table stored in the classification unit 112 according to the second embodiment of the present invention. According to the table, the classification unit 112 rejects input of low priority data if the total amount of data within the transmission expiration date is larger than the threshold value. On the other hand, according to the table, the classification unit 112 inputs all data if the total amount of data within the transmission expiration date is not greater than the threshold value. Returning to FIG. That is, the classification unit 112 restricts input of data having a low transmission priority when the stored data within the transmission validity period is larger than the threshold value.

  According to the embodiment of the present invention, when the amount of data within the transmission validity period increases, the input of some data is restricted, so that the amount of data to be stored in the packet signal can be reduced. In addition, since the input of low priority data is restricted, the influence on high priority data can be suppressed. In addition, since the amount of data to be stored in the packet signal is reduced, the processing can be executed efficiently.

(Example 3)
The third embodiment also relates to a communication system in which vehicle-to-vehicle communication is performed and road-to-vehicle communication is also performed. Until now, a free application has been executed in a terminal device mounted on a vehicle, and data from the free application has been notified from the terminal device. In the third embodiment, the terminal device is connected to the portable wireless device. The portable wireless device generates data by executing a free application. The portable wireless device transmits the generated data to the terminal device. The terminal device processes the data from the portable wireless device as before.

  FIG. 14 shows a configuration of a communication system 100 according to the third embodiment of the present invention. In the communication system 100, as an example, a first mobile radio device 150a and a second mobile radio device 150b, which are collectively referred to as a mobile radio device 150, are connected to one terminal device 14. The terminal device 14 includes an antenna 50 and a short-distance antenna 130, the first portable wireless device 150a includes a first short-distance antenna 152a, and the second portable wireless device 150b includes a second short-distance antenna. A distance antenna 152b is included. Here, the first short-range antenna 152a and the second short-range antenna 152b are collectively referred to as the short-range antenna 152. In FIG. 14, the base station device 10 and other terminal devices 14 are omitted in order to clarify the connection between the terminal device 14 and the portable wireless device 150. Further, the number of portable wireless devices 150 is not limited to two.

  The terminal device 14 and the portable wireless device 150 are connected via a short-distance antenna 130 and a short-distance antenna 152. Here, for the connection between the terminal device 14 and the portable wireless device 150, for example, a short-range wireless communication system is used. Note that, instead of the short-range wireless communication system, a wireless LAN (Local Area Network) may be used, and the terminal device 14 and the portable wireless device 150 may be connected by wire. In addition to the short-range wireless communication system, the mobile wireless device 150 is compatible with a mobile phone system. By communicating with a base station device for a mobile phone system (not shown), the mobile wireless device 150 can make a call, e-mail, data communication. Execute. Furthermore, the portable wireless device 150 may be a smart phone, and at that time, a predetermined application program may be executed. Here, since the function of the application processing unit 76 of the terminal device 14 is provided in the portable wireless device 150, the portable wireless device 150 executes a free application. The portable wireless device 150 outputs data generated by executing the free application to the terminal device 14.

  The application management unit 78 of the terminal device 14 performs the same processing as before, stores the data from the portable wireless device 150 in the packet signal and notifies the packet signal. Further, when the received packet signal includes data of a free application executed in the mobile wireless device 150, the terminal device 14 extracts the data and transmits it to the mobile wireless device 150. So far, application processing and management have been included in one terminal device 14, but here they are separated into the terminal device 14 and the portable wireless device 150. In the present embodiment, the terminal device 14 may also execute a common application or a free application.

  FIG. 15 shows the configuration of the terminal device 14. The terminal device 14 includes a short-range communication unit 132 and a short-range antenna 130 as compared with FIG. As described above, the short-range communication unit 132 communicates with the portable wireless device 150 via the short-range antenna 130 by executing communication processing corresponding to the short-range wireless communication system or the wireless LAN. When the short-range communication unit 132 receives data from the portable wireless device 150, the short-range communication unit 132 outputs the data to the application management unit 78. The data is data of a free application executed in the portable wireless device 150. These correspond to processing for the transmission side application.

  In addition, when the short-range communication unit 132 receives data from the application management unit 78, the short-range communication unit 132 transmits the data to the portable wireless device 150. The data is data processed by a free application executed in the portable wireless device 150. These correspond to processing for the receiving application. In the application processing unit 76, for example, processing for a common application is executed.

  FIG. 16 shows the configuration of the portable wireless device 150. The portable wireless device 150 includes a short-range communication unit 154, a portable wireless device application management unit 156, and a portable wireless device application processing unit 158. In FIG. 16, a configuration related to processing in the communication system 100 is shown, and a configuration related to processing in the mobile phone system and processing of a predetermined application program is omitted.

  The portable wireless device application processing unit 158 executes the same processing as the application processing unit 76 in the terminal device 14. The portable wireless device application management unit 156 executes a part of the application processing unit 76 of the terminal device 14, particularly a part of the processing close to the interface with the application management unit 78. Note that the portable wireless device application management unit 156 may be omitted. In that case, the portable wireless device application processing unit 158 and the short-range communication unit 154 are connected. The near field communication unit 154 executes processing corresponding to the near field communication unit 132.

  According to the embodiment of the present invention, since the processing is distributed to the terminal device and the portable wireless device, the processing amount at the terminal device can be reduced. In addition, since a portable wireless device is used, variations of applications to be executed can be expanded. Moreover, since the portable radio apparatus normally used by the user is incorporated in the communication system, the convenience for the user can be improved.

  In the above, this invention was demonstrated based on the Example. This embodiment is an exemplification, and it will be understood by those skilled in the art that various modifications can be made to each of those constituent elements or combinations of processing processes, and such modifications are also within the scope of the present invention. .

  In the present embodiment, the terminal device 14 is mounted on the vehicle 12. However, the present invention is not limited to this. For example, the terminal device 14 may be carried by a pedestrian. According to this modification, the application area of the terminal device 14 can be expanded.

  In the first to third embodiments of the present invention, the transmission priority is set to three levels. However, the present invention is not limited to this. For example, the transmission priority may be other than three levels. Specifically, there may be two stages or four or more stages. According to this modification, the degree of freedom of processing can be improved.

  In the second embodiment of the present invention, the classification unit 112 restricts input of low priority application data. However, the present invention is not limited to this, and for example, the classification unit 112 may limit data input of the medium priority application in addition to the low priority application. Note that the input unit 110 and the classification unit 112 may be collectively referred to as an input unit. According to this modification, the effect of reducing the data amount can be increased.

  Any combination of Examples 1 to 3 is also effective. According to this modification, it is possible to obtain the effect of any combination of the first to third embodiments.

  In each of the above embodiments, the packet signal may conform to the 700 MHz band intelligent transportation system standard.

  The outline of one embodiment of the present invention is as follows. A terminal device according to an aspect of the present invention includes an input unit that sequentially inputs data corresponding to one of a plurality of specified transmission priorities, and transmission priority among data sequentially input at the input unit. A control unit that stores in a packet signal to be transmitted in a period in which communication between terminals is possible with priority from high data.

  According to this aspect, since data having a high transmission priority is preferentially stored in the packet signal, the data can be efficiently processed in a period in which communication between terminals is possible.

  The data that is sequentially input in the input unit is given a transmission expiration date, and the control unit may discard the data that has exceeded the transmission expiration date among the data not stored in the packet signal. In this case, since data exceeding the transmission expiration date is discarded, transmission of unnecessary data can be suppressed.

  The input unit may limit input of data with low transmission priority when the data is a processing target in the control unit and the amount of data within the transmission expiration date is greater than the threshold value. . In this case, if the data within the transmission validity period increases, the input of some data is restricted, so that the amount of data to be processed can be reduced.

  The input unit sequentially inputs data to be periodically transmitted regardless of the transmission priority, and the control unit stores the data in the packet signal according to the period of the data to be periodically transmitted. When the packet signal can further store data, the packet signal may be preferentially stored in the packet signal from data having a high transmission priority. In this case, the data to be transmitted periodically is transmitted regardless of the transmission priority, so that the periodicity of the data can be maintained.

  10 base station device, 12 vehicle, 14 terminal device, 20 antenna, 22 RF unit, 24 modulation / demodulation unit, 26 processing unit, 28 control unit, 30 network communication unit, 32 frame definition unit, 34 selection unit, 36 generation unit, 50 Antenna, 52 RF unit, 54 modulation / demodulation unit, 56 processing unit, 58 control unit, 60 timing identification unit, 62 transfer determination unit, 64 acquisition unit, 66 generation unit, 68 user IF unit, 70 notification unit, 72 extraction unit, 74 Carrier sense unit, 76 application processing unit, 78 application management unit, 100 communication system, 110 input unit, 112 classification unit, 114 data storage unit for common application, 116 data storage unit for high priority application, 118 medium priority application Data storage unit, 120 low-priority application data storage unit, 122 extraction unit, 130 short-range antenna, 132 short-range communication unit, 150 portable wireless device, 152 short-range antenna, 154 short-range communication unit, 156 Application management unit in portable wireless device, 158 Application processing unit in portable wireless device, 202 network, 212 area, 214 outside area.

Claims (4)

An input unit for sequentially inputting data corresponding to one of a plurality of prescribed transmission priorities;
A control unit that stores in a packet signal to be transmitted in a period in which communication between terminals is preferentially performed from data having a high transmission priority among data sequentially input in the input unit;
A terminal device comprising: The data entered sequentially in the input unit is given a transmission expiration date,
The terminal device according to claim 1, wherein the control unit discards data that has exceeded the transmission expiration date among data not stored in the packet signal.   The input unit restricts input of data having a low transmission priority when the amount of data to be processed by the control unit and the amount of data within the transmission validity period is greater than a threshold value. The terminal device according to claim 2. The input unit sequentially inputs data to be periodically transmitted regardless of transmission priority,
The control unit stores the data in a packet signal according to the period of data to be transmitted periodically, and when the packet signal can further store data, gives priority to data with high transmission priority. 4. The terminal device according to claim 1, wherein the terminal device is stored in the packet signal.

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