JP2010212766A - Vehicular radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular radio communication system preventing an error of data due to noise. <P>SOLUTION: The vehicular radio communication system 1 includes: a radio communication part 21 of a master station 10 and a radio communication part 22 of a slave station 20 which are connected to each other by radio communication for transmitting/receiving data from/to each other; and a vehicular electronic apparatus control part 11 for distributing pattern information showing a noise pattern of vehicular apparatuses 30 to the radio communication part 21. The radio communication part 21 determines whether transmission data can be dividedly transmitted in a communication-allowing time zone in the noise pattern by dividing the transmission data to be wirelessly transmitted to the radio communication part 22 of the slave station 20 based on the distributed pattern information, and divides the transmission data into a plurality of divided data and determines a transmission condition of the plurality of divided data when the transmission data are determined to be capable of being dividedly transmitted. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle radio communication system.

  With the increase in in-vehicle electronic devices, the number of wire harnesses such as signal lines and power lines connecting the respective electronic devices has increased, and this arrangement has become important. One method for reducing the number of wires is a wireless communication system that wirelessly transmits and receives signals between electronic devices. By using a wireless communication system for communication between each electronic device, each electronic device in the vehicle only needs to supply power by connecting only the power line, and signal lines can be reduced. .

JP 2006-152663 A JP 2008-193346 A JP 2007-116258 A

  Incidentally, in general, wireless communication systems are more susceptible to disturbances than wired communication systems. In a wireless communication system, data errors may occur due to interference from other wireless communication systems, noise, and the like, and throughput may be lowered or communication may be temporarily disabled. When a wireless communication system is used for vehicle control communication that requires real-time and reliable communication, a communication system that is robust to the communication environment has been demanded.

  In order to meet such a demand, in Patent Document 1, in an in-vehicle reception system that receives a radio signal transmitted from an electronic key, generation timing of noise generated from each vehicle device using a vehicle ECU that controls the vehicle device. An in-vehicle communication control system that performs reception control to determine that the received signal is invalid when a signal is received in the specified generation timing section is proposed. By adopting this configuration, it is possible to determine that received data affected by noise is invalid. However, in Patent Document 1, since control is performed on the reception side, even if the generation timing of noise is specified, it is impossible to avoid a situation in which a transmission signal and noise that affects the signal overlap. In Patent Document 1, since it is assumed that the same data is repeatedly transmitted for device authentication, it is possible to discard the received data determined to be invalid, but it is not a general communication that repeatedly transmits data. In the case of data communication, retransmission processing is required for received data that is determined to be invalid.

  Accordingly, the present invention has been made to solve such problems, and monitors the operating state of each vehicle electronic device to grasp the noise generated from each vehicle electronic device, and grasps the grasped noise. It is an object of the present invention to provide a vehicular wireless communication system capable of maintaining a good communication environment and preventing data errors due to noise by performing communication control based on the above.

  That is, the vehicular radio communication system according to the present invention controls the vehicular electronic device and the first radio communication unit and the second radio communication unit which are connected by radio communication and transmit / receive data to / from each other. A vehicle wireless communication system including at least device control means for distributing pattern information indicating a noise pattern generated by the device to the first wireless communication means, wherein the first wireless communication means is distributed from the device control means. Based on the pattern information, the transmission data to be wirelessly transmitted to the second wireless communication means is divided to determine whether or not the transmission data can be dividedly transmitted in the communicable time zone in the noise pattern. And the transmission data are divided into a plurality of divided data when it is determined by the division transmission determination means that the divided transmission is possible. Characterized in that it comprises a dividing transmission control means for determining a Rutotomoni said plurality of transmission condition of the divided data.

  According to the present invention, the transmission data transmitted from the first wireless communication means to the second wireless communication means is divided so as to avoid the noise generated by the vehicle electronic device, and the divided data is divided into the communicable time zone in the noise pattern. Can be transmitted. For this reason, in the vehicular wireless communication system, transmission data (divided data) can be transmitted and received in a communicable time zone with a good noise environment, and transmission data errors due to noise can be prevented. In addition, even in an environment where burst noise frequently occurs, wireless communication can be performed while the operation is stabilized without frequently interrupting the operation of the vehicle electronic device.

  Further, in the vehicle wireless communication system according to the present invention, the vehicle that emits the noise pattern when transmitting the transmission data when the divided transmission control unit determines that the divided transmission determination unit cannot perform divided transmission. An interruption instruction signal for interrupting the operation of the electronic equipment for the vehicle is transmitted to the equipment control means, and the equipment control means that has received the interruption instruction signal generates the noise pattern based on the interruption instruction signal. It is preferable to interrupt the operation.

  In the vehicular wireless communication system according to the present invention, the division transmission determining means must transmit the transmission data within a certain fixed time and a minimum packet size and a transmission allowable delay time. Time) is set in advance, and the total value of the communicable time zones in the noise pattern within the transmission allowable delay time is calculated excluding the time zone smaller than the minimum packet size, and is calculated It is preferable to determine that the transmission data can be divided and transmitted when the total value of the communicable time period is larger than the total value of the plurality of pieces of divided data including the overhead portion.

  According to the present invention, it is possible to maintain a good communication environment by performing communication control based on the grasped noise and prevent data errors due to noise.

1 is a schematic configuration diagram of a vehicular wireless communication system according to an embodiment of the present invention. It is a figure which shows the relationship between noise and a transmission signal. It is a figure which shows the relationship between noise and the divided | segmented transmission signal. It is a flowchart which shows the transmission procedure of the transmission signal in a main station. It is a flowchart which shows the reply procedure of the transmission signal in a slave station. It is a flowchart which shows another transmission procedure of the transmission signal in a main station. (A) is a figure which shows the relationship between the noise at the time of changing the operation timing of an electronic device, and a transmission signal, (b) is the noise at the time of changing the transmission timing of a transmission signal, and a transmission signal. It is a figure which shows the relationship. It is a structure schematic diagram which shows another structure of the radio | wireless communications system for vehicles which concerns on embodiment of this invention.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a vehicle radio communication system according to the invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, the vehicular wireless communication system 1 includes a master station 10 and a slave station 20, and the master station 10 and the slave station 20 are connected to each other by wireless communication. In this embodiment, description will be made using one slave station 20 for convenience. However, there may be a plurality of slave stations 20. In this case, for example, a polling system is used as a communication system between the master station 10 and each slave station 20.

  The main station 10 includes a vehicle electronic device control unit 11 (device control unit), a vehicle noise database 12, and a wireless communication unit 21 (first wireless communication unit). In the main station 10, the vehicle electronic device control unit 11 is connected to the plurality of vehicle electronic devices 30, the vehicle noise database 12, and the wireless communication unit 21, and the wireless communication unit 21 is connected to the application engine 40.

  The vehicle electronic device control unit 11 controls various operations of the vehicle electronic device 30. The vehicle electronic device control unit 11 detects the start of operation when each vehicle electronic device 30 starts to operate, accesses the vehicle noise database 12, and generates a noise pattern generated by the corresponding vehicle electronic device 30. The pattern information indicating is extracted and acquired. And the vehicle electronic device control part 11 grasps | ascertains the pattern information of the vehicle electronic device 30 which is operate | moving in real time. Specifically, the vehicle electronic device control unit 11 stores the pattern information in a temporary storage device (not shown) or the like. The various pattern information is pattern information indicating a noise pattern for each time from the operation start time to the operation end time of the vehicle electronic device 30, is measured in advance, and is stored in the vehicle noise database 12. In response to a request from the wireless communication unit 21, the vehicle electronic device control unit 11 distributes the acquired pattern information to the wireless communication unit 21 of the main station 10.

  The radio communication unit 21 of the main station 10 includes an RF unit including a transmission circuit 23 and a reception circuit 24, a D / A converter 25, a modulation / encoder 26, an A / D converter 27, and an equivalent / demodulation / A BB processing unit composed of a decoder 28 and a MAC processing unit 29 (divided transmission determining means, divided transmission control means) are provided. With the above-described configuration, the wireless communication unit 21 performs processing for wirelessly communicating various signals and data related to the application engine 40 with the slave station 20. In the wireless communication processing, the MAC processing unit 29 of the wireless communication unit 21 will be described in detail later. However, the transmission conditions for transmitting data from the application engine 40 to the slave station 20 and the transmission conditions for the slave station 20 to the master station 10 are described. (Also referred to as a reply condition). The MAC processing unit 29 wirelessly transmits a transmission signal including transmission data including various data and reply condition information to the slave station 20 under the determined transmission condition. This wireless transmission is performed through the modulator / encoder 26 and D / A converter 25 of the BB processing unit and the transmission circuit 23 of the RF unit. The transmission signal from the slave station 20 is received through the reception circuit 24 of the RF unit, the A / D converter 27 and the equivalent / demodulation / decoder 28 of the BB processing unit.

  The slave station 20 includes a radio communication unit 22 (second radio communication unit) having the same configuration as the radio communication unit 21 of the master station 10 and receives a transmission signal transmitted by radio from the master station 10. The slave station 20 is connected to an application engine 40 different from the application engine 40 to which the master station 10 is connected, and outputs various data included in the received transmission signal to the connected application engine 40. In addition, the MAC processing unit 29 of the slave station 20 sends a reply signal including various data from the connected application engine 40 according to the reply condition information included in the received transmission signal under a predetermined reply condition. Wirelessly transmit to.

  Subsequently, the function of the wireless communication unit 21 of the main station 10 will be described in more detail. In the wireless communication unit 21, when the application engine 40 connected to the master station 10 outputs a transmission request instruction to the slave station 20 and various data to be transmitted to the slave station 20 to the MAC processor 29, the output is used as a trigger for the MAC. The processing unit 29 temporarily determines a transmission condition such as a transmission timing of a transmission signal from the master station 10 to the slave station 20 and a reply condition such as a reply signal return timing from the slave station 20 to the master station 10. Further, the MAC processing unit 29 acquires pattern information indicating a noise pattern of the vehicle electronic device 30 in operation from the vehicle electronic device control unit 11.

  Here, for example, as shown in FIG. 2, a transmission signal composed of transmission data having a data length T is simply transmitted between the master station 10 and the slave station 20 during the operation of the vehicle electronic device 30 (t1 to t2). If the transmission conditions are tentatively determined, noise at a predetermined interval is generated by the vehicle electronic device 30, so that each transmission signal is generated by the vehicle electronic device 30 during the time ta2 to ta3 and between the times tb2 to tb3. It overlaps with noise in the pattern, and data error due to noise occurs. Therefore, in this embodiment, the MAC processing unit 29 tentatively determines the transmission conditions and the like, and when there is an operating vehicle electronic device 30 that is generating noise, the transmission data to be wirelessly transmitted to the slave station 20 is individually transmitted. By dividing the data into divided data, it is determined whether or not the transmission data can be divided and transmitted in the communicable time zone (that is, the time zone without noise) in the noise pattern. The data is divided into a plurality of divided data, and transmission conditions for the plurality of divided data divided are determined again. Note that the communicable time zone in the noise pattern may include not only a time zone in which there is no noise, but also a time zone in which the noise value is smaller than a predetermined threshold value that does not cause a data error.

  As a method for dividing the transmission data from the master station 10 to the slave station 20 and the transmission data from the slave station 20 to the master station 10 into a plurality of divided data and transmitting the divided data, for example, as shown in FIG. The transmission signal is divided so as not to send the transmission signal between the times ta2 to ta3 and tb2 to tb3 that overlap with the noise in the noise pattern according to, and after the time ta3 has passed, and the time tb2 There is a method of performing divided transmission after each elapses.

  As described above, the MAC processing unit 29 divides the transmission data to be wirelessly transmitted to the slave station 20 based on the pattern information distributed from the vehicle electronic device control unit 11, thereby transmitting the transmission data in the communicable time zone in the noise pattern. It is determined whether or not split transmission is possible. Then, when it is determined that the divided transmission is possible, the MAC processing unit 29 divides the transmission data into a plurality of pieces of divided data and determines transmission conditions for the plurality of pieces of divided data. On the other hand, when the MAC processing unit 29 determines that the divided transmission is not possible during the operation of the specific vehicle electronic device 30 due to a long time period in which the noise is generated or the like, the MAC processing unit 29 generates the noise. An interruption instruction signal for interrupting the operation of the vehicle electronic device 30 is transmitted to the vehicle electronic device control unit 11, and the vehicle electronic device control unit 11 that has received the interruption instruction signal generates a noise pattern. The operation is interrupted, and processing for giving priority to the transmission signal to be transmitted first is performed.

  In determining whether the MAC processing unit 29 can divide transmission data and transmit it, for example, the MAC processing unit 29 sets in advance a minimum packet size and a transmission allowable delay time when dividing the transmission data. In addition, the total value of the communicable time zone in the noise pattern within the transmission allowable delay time is calculated excluding the time zone smaller than the minimum packet size, and the total value of the communicable time zone calculated is the overhead part. It may be determined whether it is larger than the total value of the plurality of pieces of divided data included, and if it is larger, it may be determined that divided transmission of transmission data is possible.

  Next, the transmission procedure of the transmission signal from the master station 10 to the slave station 20 and the reply procedure of the transmission signal from the slave station 20 to the master station 10 in the vehicular wireless communication system 1 will be described with reference to FIGS. 4 and 5.

  First, the transmission source master station 10 receives a transmission request instruction from the application engine 40, and determines whether or not to transmit a transmission signal to the transmission destination slave station 20 (S1). When determining that the transmission source main station 10 transmits a transmission signal to the slave station 20, the transmission source main station 10 transmits the transmission signal transmission timing at the master station 10 and the transmission signal transmission timing (reply timing) at the slave station 20. Are temporarily determined (S2). The main station 10 tentatively determining both transmission timings in step S2 requests the vehicle electronic device control unit 11 to obtain a noise pattern (pattern information) of the currently operating vehicle electronic device 30 (S3). ).

  Subsequently, the main station 10 that acquired the pattern information determines whether there is a vehicle electronic device 30 that generates noise at both transmission timings based on the pattern information (S4). If there is no vehicle electronic device 30 that generates noise, the process directly proceeds to step S8, and a transmission signal to the slave station 20 is generated according to the provisionally determined transmission condition. On the other hand, when determining that there is the vehicle electronic device 30 that generates noise, the main station 10 determines whether the noise can be avoided by dividing the transmission data (S5).

  As a result of the determination in step S5, if it is possible to avoid the noise and perform the divided transmission and the divided reply, the transmission timing and the reply condition are adjusted by adjusting the transmission timing of the master station 10 and the slave station 20 and the data division. Is determined again (S6), and a transmission signal to the slave station 20 is generated in accordance with the re-determined transmission conditions and the like (S8). On the other hand, if it is determined in step S5 that the divided transmission cannot be performed while avoiding noise, the operation timing is changed such as the operation interruption of the corresponding vehicle electronic device 30 (S7), and the provisionally determined transmission condition and the like In response to this, a transmission signal to the slave station 20 is generated (S8). Thereafter, when the transmission timing of the master station 10 is reached (S9), the generated transmission signal is wirelessly transmitted to the slave station 20 (S10).

  When the transmission signal is transmitted in step S10, the slave station 20 determines whether or not the transmission signal from the master station 10 has been received (S11). When determining that the transmission signal has been received, the slave station 20 acquires the transmission timing information (reply timing information) of the slave station 20 from the received transmission signal (S12). Further, the slave station 20 acquires various data to be transmitted to the master station 10 from the application engine 40, and generates a reply signal to the master station 10 (S13). When the slave station 20 reaches the transmission timing included in the transmission timing information (S14), the slave station 20 transmits data to the master station 10 (S15).

  According to the vehicle wireless communication system 1 described above, transmission data transmitted from the wireless communication unit 21 of the master station 10 to the wireless communication unit 22 of the slave station 20 is divided so as to avoid noise generated by the vehicle electronic device 30. In addition, it becomes possible to transmit each of the divided data during the communicable time zone in the noise pattern. For this reason, in the vehicular wireless communication system 1, transmission data (divided data) can be transmitted and received in a communicable time zone with a good noise environment, and transmission data errors due to noise can be prevented. In addition, even in an environment where burst noise frequently occurs, wireless communication can be performed while the operation of the vehicular electronic device 30 is not interrupted frequently and the operation is stabilized.

  The present invention is not limited to the embodiment described above. For example, when determining a transmission condition for transmitting a transmission signal from the master station 10 to the slave station 20, the priority of the wireless communication between the master station 10 and the slave station 20 is compared with the priority of the vehicle electronic device 30 in operation. Thus, the operation with the higher priority may be prioritized. In this case, for example, as shown in FIGS. 6 and 7, after passing through the same steps as steps S <b> 1 to S <b> 4 of FIG. 4, the priority of wireless communication between the master station 10 and the slave station 20 and the vehicle electronics in operation The priority of the device 30 is compared (S25). If the priority of wireless communication is high, the operation timing of the corresponding vehicle electronic device 30 is changed to prioritize wireless communication (S26, see FIG. 7A). ) If the priority of the operation of the vehicle electronic device 30 is high, the transmission data may be divided and transmitted as described above (S27).

  If the main station 10 can perform divided transmission, the transmission data is divided and transmitted (S28). If the divided data cannot be transmitted, the transmission timing of the main station 10 and the slave station 20 is changed to be after the operation of the corresponding vehicle electronic device 30. Thus (S29, see FIG. 7 (b)), transmission data errors due to noise may be prevented. As described above, by performing processing with priorities, for example, the priority of operation of the radio communication and vehicle electronic device 30 related to vehicle control is increased, and the real-time property as a vehicle radio communication system is improved. You may make it make it.

  Further, as another configuration of the vehicular wireless communication system 1, as shown in FIG. 8, the vehicular electronic device noise pattern distributor 10 a that does not include a radio communication unit and a plurality of communication terminals 50, and a plurality of communication Each terminal 50 may be configured to be connected to the vehicle electronic device noise pattern distributor 10a via the power line L. In such a vehicular radio communication system 1a, communication terminals 50 including radio communication units 51 (51a, 51b) similar to the radio communication units 21 and 22 are connected to each other by radio communication to perform autonomous distributed communication. An ad hoc network is configured, and the vehicle electronic device noise pattern distributor 10 a is connected to various vehicle electronic devices 30.

  The vehicle electronic device noise pattern distributor 10 a includes a vehicle electronic device operation state monitor 13 (device control means), a vehicle noise database 12, and a power supply / signal superimposing separation circuit 14. In response to a request from the communication terminal 50, pattern information indicating a pattern of noise to be emitted is superimposed on the voltage of the power supply line L and transmitted. The communication terminal 50 that receives the pattern information includes a power supply / signal superimposing separation circuit 52, and extracts and acquires the pattern information superimposed on the voltage of the power supply line L. One communication terminal 50a that has acquired the pattern information transmits a transmission signal as the first wireless communication means to the other communication terminal 50b corresponding to the second wireless communication means by the same method as the above-described divided transmission method. Even with such a configuration, it is possible to perform transmission division of transmission data as described above.

  The vehicular wireless communication system 1 includes a measurement mechanism that measures noise generated from the vehicular electronic device 30, and not only uses pre-measured pattern information but also appropriately measures noise and measures a plurality of measured noises. A transmission condition or the like may be determined using a noise pattern in which data is statistically processed to improve accuracy. Further, as the pattern information stored in the vehicle noise database 12, the noise pattern is not stored as it is, but the case where the noise level is higher than a preset threshold value is “not communicable” and the case where the noise level is lower is “communication”. It may be determined as “possible” and stored as binary information of “communication impossible” and “communication permitted”.

  The wireless communication units 21 and 22 may be wireless communication units using a multicarrier system such as OFDM, and a noise pattern for each frequency may be acquired to determine the transmission timing of wireless communication by the main station 10. . In this case, transmission control (transmission timing control) on the time axis and control (used subcarrier control) on the frequency axis can be performed, and the communication band can be used efficiently. Can be improved. In addition, the vehicle wireless communication system 1 is not limited to communication between wireless communication units in a vehicle, and may be used for communication outside the vehicle such as telematics such as a base station and a vehicle, or vehicle-to-vehicle communication such as a vehicle.

  DESCRIPTION OF SYMBOLS 1,1a ... Wireless communication system for vehicles, 10 ... Main station, 11 ... Vehicle electronic device control part (device control means), 12 ... Vehicle noise database, 13 ... Vehicle electronic device operation state monitor (device control means), DESCRIPTION OF SYMBOLS 20 ... Slave station, 21, 51a ... Wireless communication part (1st wireless communication means), 22, 51b ... Wireless communication part (2nd wireless communication means), 30 ... Electronic equipment for vehicles, 40 ... Application engine.

Claims (3)

First wireless communication means and second wireless communication means which are connected by wireless communication and transmit / receive data to / from each other, and at least pattern information indicating a noise pattern generated by the vehicle electronic device while controlling the vehicle electronic device. A vehicle wireless communication system including device control means for distributing to one wireless communication means,
The first wireless communication means includes
Is it possible to divide and transmit the transmission data during the communicable time zone in the noise pattern by dividing the transmission data to be wirelessly transmitted to the second wireless communication means based on the pattern information distributed from the device control means? A split transmission judging means for judging whether or not,
A division transmission control unit that divides the transmission data into a plurality of pieces of divided data and determines transmission conditions for the plurality of pieces of divided data when the division transmission judgment unit determines that division transmission is possible;
A vehicular wireless communication system.   The divided transmission control means, when it is determined by the divided transmission determination means that the divided transmission is not possible, the interruption instruction signal for interrupting the operation of the vehicle electronic device that emits the noise pattern when transmitting the transmission data 2. The device control unit that transmits to the device control unit and receives the interruption instruction signal, interrupts the operation of the vehicle electronic device that generates the noise pattern based on the interruption instruction signal. The vehicle wireless communication system described.   The divisional transmission determination means sets in advance a minimum packet size and a transmission allowable delay time when dividing the transmission data, and adds up the communicable time zone in the noise pattern within the transmission allowable delay time. The value is calculated by excluding a time zone smaller than the minimum packet size, and the transmission is performed when the calculated total value of the communicable time zone is larger than the total value of the plurality of divided data including an overhead part. The vehicular wireless communication system according to claim 1, wherein it is determined that the divided transmission of data is possible.

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