Communication network system, jamming device, management device, vehicle, program, and communication method

Abstract

To provide a communication network system capable of suppressing communication errors occurring in a specific communication device.SOLUTION: A communication network system includes a plurality of communication devices. The communication network system also includes a management device 50 that transmits a start signal to the plurality of communication devices, and a first communication device 10 which is a jamming device that transmits a jamming signal to jam sensing of the start signal by the plurality of communication devices. After sensing the start signal, the plurality of communication devices communicate using a first communication method in which each communication device transmits data in a predetermined order. The jamming device transmits the jamming signal depending on the status of a communication error in the communication network system. When a state in which the start signal is not sensed continues for a predetermined time, the plurality of communication devices switch the communication method to a second communication method in which data is transmitted when other communication devices are not transmitting data, regardless of the predetermined order.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] This invention relates to a communication network system, an interference device, a management device, a vehicle, a program, and a communication method.

Background Art

[0002] Patent Document 1 discloses a communication network system. This communication network system is composed of a plurality of communication devices. The plurality of communication devices includes a management device. The management device transmits a start signal. After the start signal is transmitted, the plurality of communication devices including the management device transmit data according to a preset order for each.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As described above, in the communication network system, by specifying the order in which each communication device transmits data, collisions of data transmitted by the communication devices are suppressed. In such a communication network system, when noise from the outside occurs periodically, communication errors such as the inability to transmit data for a specific communication device frequently may occur.

Means for Solving the Problems

[0005] Hereinafter, means for solving the above problems and their effects will be described. A communication network system for solving the above problems is composed of a plurality of communication devices. The communication network system includes a management device that transmits a start signal to the plurality of communication devices, and an interference device that transmits an interference signal for interfering with the detection of the start signal by the plurality of communication devices. In the communication network system, after the plurality of communication devices detect the start signal, they communicate with each other using a first communication method in which each of the communication devices transmits data in a predetermined order. In the communication network system, the interference device transmits the interference signal according to the communication error situation in the communication network system. In the communication network system, when the state of not detecting the start signal by the plurality of communication devices continues for a predetermined time, the communication method is switched to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order.

[0006] An interference device for solving the above problems is applied to a communication network system including a plurality of communication devices and a management device that transmits a start signal to the communication devices. After detecting the start signal, the plurality of communication devices communicate with each other using a first communication method in which each of the communication devices transmits data in a predetermined order. On the other hand, when the state of not detecting the start signal by the plurality of communication devices continues for a predetermined time, the communication method is set to be switched to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order. The interference device transmits an interference signal for interfering with the detection of the start signal by the communication devices according to the communication error situation in the communication network system.

[0007] A communication network system for solving the above problems is composed of a plurality of communication devices. The communication network system includes a management device that transmits a start signal to the plurality of communication devices. In the communication network system, after the plurality of communication devices sense the start signal, they communicate with each other using a first communication method in which each of the communication devices transmits data in a predetermined order. In the communication network system, the management device stops transmitting the start signal according to the communication error situation in the communication network system. In the communication network system, when the state in which the plurality of communication devices do not sense the start signal continues for a predetermined time, the communication method is switched to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order.

[0008] A management device for solving the above problems transmits a start signal in a communication network system composed of a plurality of communication devices. After the plurality of communication devices sense the start signal, they communicate with each other using a first communication method in which each of the communication devices transmits data in a predetermined order. On the other hand, when the state in which the plurality of communication devices do not sense the start signal continues for a predetermined time, the communication method is set to be switched to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order. The management device stops transmitting the start signal according to the communication error situation in the communication network system.

[0009] A communication network system provided in a vehicle for solving the above problems is composed of a plurality of communication devices. A vehicle equipped with the communication network system includes a management device that transmits a start signal to the plurality of communication devices, and an interference device that transmits an interference signal for interfering with the detection of the start signal by the plurality of communication devices. In a vehicle equipped with the communication network system, after the plurality of communication devices detect the start signal, they communicate with each other using a first communication method in which each of the communication devices transmits data in a predetermined order. In a vehicle equipped with the communication network system, the interference device transmits the interference signal according to the communication error situation in the communication network system. In a vehicle equipped with the communication network system, when the state in which the plurality of communication devices do not detect the start signal continues for a predetermined time, the communication method is switched to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order.

[0010] A vehicle equipped with a communication network system for solving the above problems is composed of a plurality of communication devices. A vehicle equipped with the communication network system includes a management device that transmits a start signal to the plurality of communication devices. In a vehicle equipped with the communication network system, after the plurality of communication devices detect the start signal, they communicate with each other using a first communication method in which each of the communication devices transmits data in a predetermined order. In a vehicle equipped with the communication network system, the management device stops transmitting the start signal according to the communication error situation in the communication network system. In a vehicle equipped with the communication network system, when the state in which the plurality of communication devices do not detect the start signal continues for a predetermined time, the communication method is switched to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order.

[0011] The program for solving the above problems is applied to a jamming device of a communication network system. The communication network system includes a plurality of communication devices and a management device that transmits a start signal. After sensing the start signal, the plurality of communication devices communicate with each other using a first communication method in which each piece of data is transmitted in a predetermined order. On the other hand, when the state of not sensing the start signal continues for a predetermined time, the plurality of communication devices are set to switch the communication method to a second communication method in which data is transmitted when no other communication device is transmitting data, regardless of the predetermined order. The program causes the jamming device to transmit a jamming signal that interferes with the sensing of the start signal by the communication device based on the communication error situation in the communication network system.

[0012] The program for solving the above problems is applied to a management device that transmits a start signal in a communication network system composed of a plurality of communication devices. After sensing the start signal, the plurality of communication devices communicate with each other using a first communication method in which each piece of data is transmitted in a predetermined order. On the other hand, when the state of not sensing the start signal continues for a predetermined time, the plurality of communication devices are set to switch the communication method to a second communication method in which data is transmitted when no other communication device is transmitting data, regardless of the predetermined order. The program causes the management device to stop the transmission of the start signal based on the communication error situation in the communication network system.

[0013] The communication method for solving the above problems is a communication method in a communication network system. The communication network system is composed of a plurality of communication devices. The communication network system includes a management device that transmits a start signal and a jamming device that transmits a jamming signal for interfering with the detection of the start signal by the communication device. In the communication network system, after the plurality of communication devices detect the start signal, they communicate with each other using a first communication method in which each piece of data is transmitted in a predetermined order. The communication method includes a step in which the jamming device transmits the jamming signal based on the communication error situation in the communication network system. The communication method includes a step of switching the communication method to a second communication method in which, when the state in which the plurality of communication devices do not detect the start signal continues for a predetermined time, each of the other communication devices transmits data when no other communication device is transmitting data, regardless of the predetermined order.

[0014] The communication method for solving the above problems is a communication method in a communication network system. The communication network system is composed of a plurality of communication devices. The communication network system includes a management device that transmits a start signal. In the communication network system, after the plurality of communication devices detect the start signal, they communicate with each other using a first communication method in which each piece of data is transmitted in a predetermined order. The communication method includes a step in which the management device stops transmitting the start signal based on the communication error situation in the communication network system. The communication method includes a step of switching the communication method to a second communication method in which, when the state in which the plurality of communication devices do not detect the start signal continues for a predetermined time, each of the other communication devices transmits data when no other communication device is transmitting data, regardless of the predetermined order.

Advantages of the Invention

[0015] The communication network system, the jamming device, the management device, the vehicle, the program, and the communication method can suppress communication errors occurring in a specific communication device.

Brief Description of the Drawings

[0016]

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DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of the communication network system will be described with reference to FIGS. 1 to 12. <Configuration of Communication Network System 100> As shown in FIG. 1, the communication network system 100 is composed of a plurality of communication devices. The plurality of communication devices are communicably connected to each other through a communication bus 30.

[0018] The communication network system 100 is applied to a vehicle. And the plurality of communication devices constituting the communication network system 100 are electronic control units (ECUs: Electronic Control Unit) in the vehicle. The plurality of communication devices realize specific functions in the vehicle while communicating with each other through the communication bus 30.

[0019] One of the plurality of communication devices constituting the communication network system 100 is the management device 50. As shown in FIG. 1, the management device 50 includes a processing device 51 and a storage device 52. A program is stored in the storage device 52. The processing device 51 executes various processes by executing the program stored in the storage device 52. The processing device 51 includes a processor.

[0020] One of the plurality of communication devices constituting the communication network system 100 is the first communication device 10. As shown in FIG. 1, the first communication device 10 includes a processing device 11 and a storage device 12. A program is stored in the storage device 12. The program stored in the storage device 12 includes a program for controlling the communication methods of the plurality of communication devices in the communication network system 100. The processing device 11 executes various processes by executing the program stored in the storage device 12. The processing device 11 includes a processor.

[0021] One of the plurality of communication devices constituting the communication network system 100 is the second communication device 20. As shown in FIG. 1, the second communication device 20 includes a processing device 21 and a storage device 22. A program is stored in the storage device 22. The processing device 21 executes various processes by executing the program stored in the storage device 22. The processing device 21 includes a processor.

[0022] Each communication device transmits data through the communication bus 30 to realize a specific function. Hereinafter, the data transmitted by the first communication device 10 is referred to as first data 41. The data transmitted by the second communication device 20 is referred to as second data 42. The data transmitted by the management device 50 is referred to as third data 43. Each communication device uses the first communication method as a communication method for communicating data with each other.

[0023] Each communication device does not transmit data when the function it realizes is not necessary for vehicle control. That is, the first data 41 to the third data 43 are not transmitted at timings that are not necessary for vehicle control.

[0024] In addition to the third data 43, the management device 50 transmits a start signal 40. The start signal 40 will be described later. Also, in addition to the first data 41, the first communication device 10 transmits an interference signal. The interference signal will also be described later.

[0025] As described above, in this embodiment, the communication network system 100 is composed of three communication devices and one communication bus. The number of communication devices included in the communication network system 100 is not limited to this embodiment. Also, the connection mode of each communication device, that is, the topology of the communication network system 100 is not limited to this embodiment.

[0026] <Overview of the First Communication Method> FIG. 2 shows an example of the mode in which data is transmitted to the communication bus 30 in the first communication method. The rectangles in FIG. 2 indicate the data transmitted by each communication device. The rectangles in FIG. 2 are represented with an area that is proportional to the data capacity. Therefore, in FIG. 2, it means that the second data 42 has the largest capacity. Note that each communication device does not always transmit data of the same capacity. Therefore, although the second data 42 is represented as having the largest capacity in FIG. 2, the second data 42 does not necessarily have the largest capacity at other timings.

[0027] In FIG. 2, the data is transmitted in order from left to right. As shown in FIG. 2, in the first communication method, first, the start signal 40 is transmitted. The management device 50 transmits the start signal 40 periodically. The start signal 40 is a signal that notifies each communication device connected to the communication bus 30 that data communication by the first communication method has started.

[0028] Each communication device that senses the start signal 40 transmits data by the first communication method if it has data to transmit. In the first communication method, the order in which each communication device transmits data after the start signal 40 is transmitted is determined in advance. This order may be determined when the communication network system 100 is constructed, or the management device 50 may determine the order. When the management device 50 determines the order, each communication device can know the data transmission order by the management device 50 including information indicating the order in the start signal 40 or other signals and transmitting them.

[0029] In the example shown in FIG. 2, in the communication network system 100, after the start signal 40 is transmitted, the first communication device 10 transmits the first data 41. Also, in the example shown in FIG. 2, in the communication network system 100, after the first data 41 is transmitted, the second communication device 20 transmits the second data 42. And, in the example shown in FIG. 2, in the communication network system 100, after the second data 42 is transmitted, the management device 50 transmits the third data 43. Note that the order in which communication devices transmit data in the first communication method is not limited to this embodiment.

[0030] In this way, each communication device transmits data in order after the start signal 40 is transmitted. Each communication device grasps which communication device is currently in the order of transmitting data in order to transmit data in order after the start signal 40 is transmitted.

[0031] In the example shown in FIG. 2, immediately after the start signal 40 is transmitted, each communication device grasps that currently the first communication device 10 is in the order of transmitting the first data 41. In the example shown in FIG. 2, after the first data 41 is transmitted, each communication device recognizes that it is now the order in which the second communication device 20 transmits the second data 42. As described above, the first data 41 to the third data 43 are not transmitted at timings that are not necessary for vehicle control. That is, depending on the function to be executed and the content of the information to be communicated, the first communication device 10 may not transmit the first data 41. In this case, each communication device determines that the first communication device 10 does not transmit data when a certain period of time has elapsed without the first data 41 being transmitted after the order in which the first communication device 10 transmits the first data 41. Then, when a certain period of time has elapsed without the first data 41 being transmitted, it is recognized that it is now the order in which the second communication device 20 transmits the second data 42.

[0032] In the example shown in FIG. 2, after the second data 42 is transmitted, each communication device recognizes that it is now the order in which the management device 50 transmits the third data 43. When the second communication device 20 does not transmit the second data 42, each communication device determines that the second communication device 20 does not transmit data when a certain period of time has elapsed without the second data 42 being transmitted after the order in which the second communication device 20 transmits the second data 42. Then, when a certain period of time has elapsed without the second data 42 being transmitted, it is recognized that it is now the order in which the management device 50 transmits the third data 43.

[0033] FIG. 3 shows the communication among the first communication device 10, the second communication device 20, and the management device 50 in the first communication method. As shown in FIG. 3, in the first communication method, first, the management device 50 transmits a start signal 40 toward the first communication device 10 and the second communication device 20.

[0034] Next, the first communication device 10 transmits the first data 41 toward the management device 50 and the second communication device 20. At this time, the first communication device 10 transmits the first data 41 after recognizing that it is now the order in which it transmits data itself. Note that depending on the function to be executed and the content of the information to be communicated, the first communication device 10 may not transmit the first data 41.

[0035] Next, the second communication device 20 transmits the second data 42 to the management device 50 and the first communication device 10. At this time, the second communication device 20 transmits the second data 42 after grasping the order in which it currently transmits data. Note that, similar to the first communication device 10, depending on the functions to be executed and the content of the information to be communicated, the second communication device 20 may not transmit the second data 42.

[0036] Next, the management device 50 transmits the third data 43 to the first communication device 10 and the second communication device 20. At this time, the management device 50 transmits the third data 43 after grasping the order in which it currently transmits data. Note that, similar to the first communication device 10, depending on the functions to be executed and the content of the information to be communicated, the management device 50 may not transmit the third data 43.

[0037] <Processes Executed by the Processing Devices of Each Communication Device in the First Communication Method> FIG. 4 shows a series of processes executed by each communication device in the communication network system 100 in the first communication method. The first communication device 10, the second communication device 20, and the management device 50 each execute the processes shown in FIG. 4 after grasping the order in which they currently transmit data.

[0038] This series of processes is executed by the processing devices of each communication device in the communication network system 100. That is, this series of processes is executed by the processing device 11 of the first communication device 10, the processing device 21 of the second communication device 20, and the processing device 51 of the management device 50, respectively.

[0039] First, the flow when the processing device 11 of the first communication device 10 executes the series of processes shown in FIG. 4 will be described. As shown in FIG. 4, when starting this series of processes, in the process of step S11, the processing device 11 determines whether there is data to be transmitted by itself. That is, the processing device 11 determines whether the first communication device 10 needs to transmit the first data 41.

[0040] In the process of step S11, when the processing device 11 determines that there is no data to be transmitted by itself (step S11: NO), that is, when it determines that there is no need to transmit the first data 41, this series of processes ends.

[0041] On the other hand, in the process of step S11, when the processing device 11 determines that there is data to be transmitted by itself (step S11: YES), that is, when it determines that there is a need to transmit the first data 41, the process proceeds to step S12. In the process of step S12, the processing device 11 transmits the first data 41. The processing device 11 that has transmitted the first data 41 ends this series of processes.

[0042] The processing device 21 of the second communication device 20 also executes the same processing as the processing device 11 of the first communication device 10. As shown in FIG. 4, when this series of processes is started, in the process of step S11, the processing device 21 determines whether there is data to be transmitted by itself. That is, the processing device 21 determines whether the second communication device 20 needs to transmit the second data 42.

[0043] In the process of step S11, when the processing device 21 determines that there is no data to be transmitted by itself (step S21: NO), that is, when it determines that there is no need to transmit the second data 42, this series of processes ends.

[0044] On the other hand, in the process of step S11, when the processing device 21 determines that there is data to be transmitted by itself (step S11: YES), that is, when it determines that there is a need to transmit the second data 42, the process proceeds to step S12. In the process of step S12, the processing device 21 transmits the second data 42. The processing device 21 that has transmitted the second data 42 ends this series of processes.

[0045] The processing device 51 of the management device 50 also executes the same processing as the processing device 11 of the first communication device 10. As shown in FIG. 4, when starting this series of processes, in the process of step S11, the processing device 51 determines whether there is data to be transmitted by itself. That is, the processing device 51 determines whether the management device 50 needs to transmit the third data 43.

[0046] In the process of step S11, if the processing device 51 determines that there is no data to be transmitted by itself (step S11: NO), that is, if it determines that there is no need to transmit the third data 43, this series of processes ends.

[0047] On the other hand, in the process of step S11, if the processing device 51 determines that there is data to be transmitted by itself (step S11: YES), that is, if it determines that there is a need to transmit the third data 43, the process proceeds to step S12. In the process of step S12, the processing device 51 transmits the third data 43. The processing device 51 that has transmitted the third data 43 ends this series of processes.

[0048] <Overview of the Second Communication Method> As described above, in the communication network system 100, each communication device communicates with each other by transmitting data using the first communication method. In the first communication method, the order in which each communication device transmits data is predetermined. And each communication device transmits data in a predetermined order using the start signal 40 transmitted by the management device 50 as a signal.

[0049] In such a communication method, since the timing of transmitting the start signal 40 is regular and the order in which the communication devices transmit is fixed, the timing at which each communication device transmits data may be periodic to some extent. Therefore, in the first communication method, when noise from the outside occurs periodically, the timing at which a specific communication device transmits data may coincide with the timing at which the noise occurs. In that case, for that communication device, as long as the data transmission timing coincides with the noise generation timing, a communication error such as being unable to transmit data will occur.

[0050] In addition to the above-described aspects, in the first communication method, for example, due to the occurrence of noise, there may be a case where a message cannot be received normally. Also, in the first communication method, for example, due to the occurrence of noise, the transmission time of data is restricted, and there may be a case where the data to be transmitted cannot be fully transmitted. Thus, in the first communication method, various communication errors may occur due to the occurrence of noise.

[0051] When such a communication error due to noise occurs, the communication network system 100 switches the communication method of the communication device from the first communication method to the second communication method. FIG. 5 shows an example of the manner in which data is transmitted to the communication bus 30 in the second communication method. The rectangles in FIG. 5 indicate the data transmitted by the respective communication devices, similar to FIG. 2. And the rectangles in FIG. 5 are represented with areas proportional to the capacity of the data, similar to FIG. 2. Therefore, in FIG. 2, it means that the second data 42 has the largest capacity. Note that each communication device does not always transmit data of the same capacity. Therefore, although the second data 42 is represented as having the largest capacity in FIG. 2, the second data 42 is not necessarily the largest in capacity at another timing.

[0052] Also in FIG. 5, the data is transmitted in order from the left, similar to FIG. 2. In the example of the manner shown in FIG. 5, first, the second communication device 20 is transmitting the second data 42. Next, the management device 50 is transmitting the third data 43. And then, next, the first communication device 10 is transmitting the first data 41.

[0053] As in the example shown in FIG. 5, in the second communication method, unlike the first communication method, the start signal 40 is not transmitted. Therefore, in the second communication method, each communication device transmits data at an arbitrary timing without waiting for the transmission of the start signal 40 by the management device 50.

[0054] Also, in the example of the aspect shown in FIG. 2, data is transmitted in the order of first data 41, second data 42, and third data 43. On the other hand, in the example of the aspect shown in FIG. 5, data is transmitted in the order of second data 42, third data 43, and first data 41. As described above, in the second communication method, the communication device transmits data at an arbitrary timing. That is, in the second communication method, unlike the first communication method, the order in which data is transmitted is not fixed. Therefore, the order in which the communication device transmits data in the second communication method is not limited to the order shown in FIG. 5.

[0055] In the second communication method, since the order in which the communication device transmits data is not fixed, there is a possibility that the timings at which a plurality of communication devices transmit data may coincide. At this time, since the data collide with each other, the communication device cannot transmit data to other communication devices. Therefore, in the second communication method, the communication device transmits data after confirming that no other communication device is transmitting data.

[0056] Also, even if it is confirmed that no other communication device is transmitting data, if a plurality of communication devices start transmitting data at the same time, the data will collide with each other. In this case, the communication device detects that the data have collided with each other. Then, the communication device re-transmits the data that it could not transmit after confirming that no other communication device is transmitting data, leaving a time interval. By repeating such re-transmissions, the communication device can finally transmit the data.

[0057] Thus, in the second communication method, each communication device in the communication network system 100 transmits data when no other communication device is transmitting data, regardless of the predetermined order.

[0058] Figure 6 shows the communication among the first communication device 10, the second communication device 20, and the management device 50 in the second communication method. As described above, in the second communication method, the order in which each communication device transmits data is not fixed. Figure 6 shows the communication when each communication device transmits data in the order shown in Figure 5.

[0059] In the example of Figure 6, first, the second communication device 20 transmits the second data 42 to the first communication device 10 and the management device 50. At this time, the second communication device 20 transmits the second data 42 after confirming that the management device 50 and the first communication device 10 are not transmitting data.

[0060] In the example of Figure 6, next, the management device 50 transmits the third data 43 to the first communication device 10 and the second communication device 20. At this time, the management device 50 transmits the third data 43 after confirming that the first communication device 10 and the second communication device 20 are not transmitting data.

[0061] In the example of Figure 6, next, the first communication device 10 transmits the first data 41 to the second communication device 20 and the management device 50. At this time, the first communication device 10 transmits the first data 41 after confirming that the management device 50 and the second communication device 20 are not transmitting data.

[0062] <Processes Executed by the Processing Devices of Each Communication Device in the Second Communication Method> Figure 7 shows a series of processes executed when each communication device in the communication network system 100 transmits data in the second communication method. That is, the first communication device 10, the second communication device 20, and the management device 50 each execute the processes shown in Figure 7 when transmitting data.

[0063] This series of processes is executed by the processing devices of each communication device in the communication network system 100. That is, this series of processes is executed by the processing device 11 of the first communication device 10, the processing device 21 of the second communication device 20, and the processing device 51 of the management device 50.

[0064] First, the flow when the processing device 11 of the first communication device 10 executes the series of processes shown in FIG. 7 will be described. As shown in FIG. 7, when starting this series of processes, in the process of step S21, the processing device 11 determines whether there is a communication device that is transmitting data in the communication network system 100. At this time, when the first communication device 10 has received the third data 43 transmitted by the management device 50 or the second data 42 transmitted by the second communication device 20, the processing device 11 determines that there is a communication device that is transmitting data.

[0065] In the process of step S21, when the processing device 11 determines that there is a communication device that is transmitting data (step S21: YES), the process of step S21 is repeated. On the other hand, in the process of step S21, when the processing device 11 determines that there is no communication device that is transmitting data (step S21: NO), the process proceeds to step S22. In the process of step S22, the processing device 11 transmits data. Since the data transmitted by the first communication device 10 is the first data 41, the processing device 11 transmits the first data 41 in the process of step S22.

[0066] In the next process of step S23, the processing device 11 determines whether the transmitted data has collided with other data. When a communication device in the communication network system 100 detects a data collision, any communication device in the communication network system 100 that has detected the collision transmits a jam signal. A jam signal is a signal notifying that there has been a data collision. The processing device 11 determines whether the transmitted data has collided with other data based on whether it has received a jam signal.

[0067] In the process of step S23, when the processing device 11 determines that the transmitted data has collided with other data (step S23: YES), the process proceeds to step S24. In the process of step S24, the processing device 11 retransmits the first data 41. At this time, if the processing device 11 retransmits the first data 41 immediately after the data collision occurs, there is a possibility of colliding with the collided data again. Therefore, the processing device 11 transmits the first data 41 after a time interval. Note that the communication device that transmitted the data that collided with the first data 41 also retransmits the data after a time interval, similar to the processing device 11. Therefore, when the time interval left by the processing device 11 and the time interval left by the communication device are different, the processing device 11 and the communication device can transmit the data without colliding again. The processing device 11 that has retransmitted the first data 41 executes the process of step S23 again.

[0068] In the process of step S23, when the processing device 11 determines that the transmitted data has not collided with other data (step S23: NO), it ends the series of processes shown in FIG. 7.

[0069] The processing device 21 of the second communication device 20 also executes the series of processes shown in FIG. 7, similar to the processing device 11. As shown in FIG. 7, when starting this series of processes, in the process of step S21, the processing device 21 determines whether there is a communication device that is transmitting data in the communication network system 100. At this time, the processing device 21 determines that there is a communication device that is transmitting data when the second communication device 20 has received the third data 43 transmitted by the management device 50 or the first data 41 transmitted by the first communication device 10.

[0070] In the process of step S21, when the processing device 21 determines that there is a communication device that is transmitting data (step S21: YES), it repeats the process of step S21. On the other hand, in the process of step S21, if the processing device 21 determines that there is no communication device transmitting data (step S21: NO), the process proceeds to step S22. In the process of step S22, the processing device 21 transmits data. Since the data transmitted by the second communication device 20 is the second data 42, the processing device 21 transmits the second data 42 in the process of step S22.

[0071] In the process of the next step S23, the processing device 21 determines whether the transmitted data has collided with other data. The processing device 21 determines whether the transmitted data has collided with other data based on whether a jam signal has been received.

[0072] In the process of step S23, if the processing device 21 determines that the transmitted data has collided with other data (step S23: YES), the process proceeds to step S24. In the process of step S24, the processing device 21 retransmits the second data 42. At this time, the processing device 21 transmits the second data 42 after a time interval. The processing device 21 that has retransmitted the second data 42 executes the process of step S23 again.

[0073] In the process of step S23, if the processing device 21 determines that the transmitted data has not collided with other data (step S23: NO), the series of processes shown in FIG. 7 is terminated.

[0074] The processing device 51 of the management device 50 also executes the series of processes shown in FIG. 7 in the same manner as the processing device 11. As shown in FIG. 7, when this series of processes is started, in the process of step S21, the processing device 51 determines whether there is a communication device transmitting data in the communication network system 100. At this time, the processing device 51 determines that there is a communication device transmitting data when the management device 50 has received the first data 41 transmitted by the first communication device 10 or the second data 42 transmitted by the second communication device 20.

[0075] In the process of step S21, when the processing device 51 determines that there is a communication device transmitting data (step S21: YES), the process of step S21 is repeated. On the other hand, in the process of step S21, when the processing device 51 determines that there is no communication device transmitting data (step S21: NO), the process proceeds to step S22. In the process of step S22, the processing device 51 transmits data. Since the data transmitted by the management device 50 is the third data 43, the processing device 51 transmits the third data 43 in the process of step S22.

[0076] In the next step S23, the processing device 51 determines whether the transmitted data has collided with other data. The processing device 51 determines whether the transmitted data has collided with other data based on whether a jam signal is received.

[0077] In the process of step S23, when the processing device 51 determines that the transmitted data has collided with other data (step S23: YES), the process proceeds to step S24. In the process of step S24, the processing device 51 retransmits the second data 42. At this time, the processing device 51 transmits the third data 43 after a time interval. The processing device 21 that has retransmitted the third data 43 executes the process of step S23 again.

[0078] In the process of step S23, when the processing device 51 determines that the transmitted data has not collided with other data (step S23: NO), the series of processes shown in FIG. 7 is terminated.

[0079] <Data transmission and reception when a communication device switches communication methods> As described above, when communication errors frequently occur for a specific communication device in the first communication method, the communication network system 100 switches the communication method to the second communication method. FIG. 8 shows a specific example of communication among the first communication device 10, the second communication device 20, and the management device 50 when such a communication method is switched.

[0080] The communication shown in FIG. 8 is executed when two conditions are satisfied. The first condition is that the number of communication errors occurring while any communication device in the communication network system 100 transmits data a predetermined number of times is equal to or greater than a preset value. The preset value will be described later.

[0081] The second condition is that the communication device in the communication network system 100 can shift to the second communication method. The state in which the communication device can shift to the second communication method is a state in which switching the communication method by shifting the communication device to the second communication method does not hinder the operation of the vehicle. As described above, in the second communication method, data cannot be transmitted when another communication device is transmitting data. That is, in the second communication method, the opportunity for each communication device to transmit data is not guaranteed. Therefore, depending on the situation of the vehicle, switching the communication method of the communication device in the communication network system 100 may cause a specific communication device to be unable to transmit data for a long period of time. The communication network system 100 does not switch the communication method of the communication device to the second communication method in order to prioritize ensuring the data transmission opportunity depending on the situation of the vehicle.

[0082] When such two conditions are satisfied, as shown in the upper part of FIG. 8, the first communication device 10 transmits an interference signal. The interference signal is a signal that interferes with the detection of the start signal 40 by each communication device in the communication network system 100. Thus, in this example, the first communication device 10 is an interference device that transmits an interference signal according to the communication error situation.

[0083] The first communication device 10 transmits an interference signal at the timing when the management device 50 transmits the start signal 40. As a result, the first communication device 10, the second communication device 20, and the management device 50 no longer detect the start signal 40.

[0084] As shown in the middle part of FIG. 8, when the state in which the first communication device 10, the second communication device 20, and the management device 50 do not detect the start signal 40 continues for a predetermined time, they shift to the second communication method. In this way, each communication device in the communication network system 100 switches the communication method to the second communication method.

[0085] As shown in the middle part of FIG. 8, after the first communication device 10, the second communication device 20, and the management device 50 shift to the second communication method, they communicate with each other using the second communication method. That is, the first communication device 10, the second communication device 20, and the management device 50 communicate with each other in the manner exemplified in FIG. 6.

[0086] As shown in the lower part of FIG. 8, after the management device 50 shifts to the second communication method, when the state in which data is not transmitted continues for a certain time, the management device 50 transmits the start signal 40. The first communication device 10 and the second communication device 20 that have received the start signal 40 shift to the first communication method. Also, the management device 50 that has transmitted the start signal 40 also shifts to the first communication method. In this way, each communication device in the communication network system 100 returns the communication method to the first communication method.

[0087] <Status of communication error acquired by the first communication device 10> In the specific example shown in FIG. 8, as described above, the first communication device 10 transmits an interference signal according to the status of the communication error. Since the first communication device 10 transmits an interference signal as necessary, it acquires the status of the communication error in the communication network system 100.

[0088] FIG. 9 is a table showing the communication error status in the communication network system 100 acquired by the first communication device 10. As shown in FIG. 9, the first communication device 10 acquires information on the number of communication errors that occurred while each communication device transmits data a predetermined number of times as the communication error status. That is, the first communication device 10 acquires information on the number of communication errors that occurred for each of the communication devices, namely, the first communication device 10 itself, the second communication device 20, and the management device 50, while transmitting data a predetermined number of times. In FIG. 9, the number of communication errors of each communication device acquired by the first communication device 10 is represented by symbols such as "A1", "A2", "A3".

[0089] As shown in FIG. 9, a default value is set for each communication device. The default value is a threshold value for the first communication device 10 to determine whether to switch the communication method used by the communication device from the first communication method to the second communication method based on the number of communication errors in the communication device. The first communication device 10 transmits an interference signal when the number of communication errors for any communication device becomes equal to or greater than the default value. In FIG. 9, the default values set for each communication device are represented by symbols such as "B1", "B2", "B3".

[0090] <Processing when the first communication device 10 transmits an interference signal> FIG. 10 shows a series of processes executed when the first communication device 10 transmits an interference signal. This series of processes is executed by the processing device 11 of the first communication device 10 performing processing according to a program stored in the storage device 12.

[0091] This series of processes is executed when the first communication device 10 acquires information on the number of communication errors that occurred while transmitting data a predetermined number of times for any of the first communication device 10 itself, the second communication device 20, and the management device 50.

[0092] As shown in FIG. 10, when starting this series of processes, in the process of step S101, the processing device 11 determines whether the number of communication errors in the communication device for which the information was acquired is equal to or greater than the default value.

[0093] In the process of step S101, when the processing device 11 determines that the number of communication errors is not more than a preset value (step S101: NO), that is, when it determines that the number of communication errors is less than the preset value, this series of processes ends.

[0094] In the process of step S101, when the processing device 11 determines that the number of communication errors is greater than or equal to the preset value (step S101: YES), the process proceeds to step S102.

[0095] In the process of step S102, the processing device 11 grasps the situation of the vehicle. The processing device 11 grasps the situation of the vehicle based on the data transmitted by the communication device in the communication network system 100. For example, when the situation of the vehicle is during autonomous driving, the communication device that realizes the function of autonomous driving by communicating during autonomous driving in the communication network system 100 transmits data indicating that the situation of the vehicle is during autonomous driving.

[0096] In the next step S103 process, the processing device 11 determines whether the communication device in the communication network system 100 can switch to the second communication method. In the process of step S103, the processing device 11 determines whether the communication device can switch to the second communication method based on the vehicle situation grasped in the process of step S102.

[0097] The processing device 11 determines that the communication device cannot switch to the second communication method for vehicle situations that require prioritizing ensuring data transmission opportunities. For example, when the situation of the vehicle is during autonomous driving, the processing device 11 determines that the communication device cannot switch to the second communication method. Also, for example, when the situation of the vehicle is during fault diagnosis, the processing device 11 determines that the communication device cannot switch to the second communication method.

[0098] In the process of step S103, when the processing device 11 determines that the communication device cannot shift to the second communication method (step S103: NO), this series of processes ends. In the process of step S103, when the processing device 11 determines that the communication device can shift to the second communication method (step S103: YES), the process proceeds to step S104. In the process of step S104, the processing device 11 transmits an interference signal. This process corresponds to the process executed by the first communication device 10 in the upper part of FIG. 8. In this way, the processing device 11 transmits an interference signal based on the acquired communication error situation and the grasped vehicle situation.

[0099] The processing device 11 that has transmitted the interference signal ends this series of processes. <Processing for the communication device to switch the communication method to the second communication method> FIG. 11 shows a series of flows when each communication device in the communication network system 100 switches the communication method from the first communication method to the second communication method. This series of processes is executed by the processing device 11 of the first communication device 10, the processing device 21 of the second communication device 20, and the processing device 51 of the management device 50. This process corresponds to the process executed by the first communication device 10, the second communication device 20, and the management device 50 shown in the middle part of FIG. 8.

[0100] First, the flow when the processing device 11 of the first communication device 10 executes the series of processes shown in FIG. 11 will be described. The processing device 11 executes the series of processes shown in FIG. 11 when it does not sense the start signal 40 for a predetermined time.

[0101] As shown in FIG. 11, when starting this series of processes, in the process of step S31, the processing device 11 shifts to the second communication method. At this time, the processing device 11 switches the flag for determining the communication method in the first communication device 10 from the flag of the first communication method to the flag of the second communication method. Thereby, the communication method in the first communication device 10 shifts from the first communication method to the second communication method. In this way, the first communication device 10 switches the communication method from the first communication method to the second communication method.

[0102] In the next step S32, the processing device 11 determines whether there is data to be transmitted. At this time, the processing device 11 determines whether there is data to be transmitted based on whether the first communication device 10 needs to transmit the first data 41.

[0103] In step S32, when the processing device 11 determines that there is no data to be transmitted (step S32: NO), this series of processes ends. In step S32, when the processing device 11 determines that there is data to be transmitted (step S32: YES), the process proceeds to step S33. In the process of step S33, the processing device 11 executes offset time setting processing.

[0104] The offset time setting process is a process of setting an offset time from the moment of switching to the second communication method until the transmission of the data starts when there is data to be transmitted immediately after switching the communication method to the second communication method. In the second communication method, the order in which each communication device transmits data is not set. Each communication device suppresses data collision immediately after switching the communication method to the second communication method by providing an offset time from the moment of switching to the second communication method until the transmission of the data starts.

[0105] When setting the offset time, the processing device 11, for example, sets the offset time shorter as the capacity of the first data 41 to be transmitted is larger. Thereby, the processing device 11 can preferentially transmit the first data 41 with a large capacity in the second communication method.

[0106] When setting the offset time, for example, the processing device 11 sets the offset time shorter as the priority of the first communication device 10 is higher. In this case, the priority of each communication device in the communication network system 100 is determined in advance. By setting the offset time shorter as the priority is higher, the communication device with a higher priority can transmit data preferentially in the communication network system 100.

[0107] In the process of the next step S34, the processing device 11 transmits data in consideration of the offset time. At this time, the processing device 11 starts transmitting the first data 41 after the elapse of the offset time set in the process of step S33.

[0108] The processing device 11 that has transmitted the first data 41 ends this series of processes. Regarding the processing device 21 of the second communication device 20, it also executes the series of processes shown in FIG. 11 in the same manner as the processing device 11. The processing device 21 executes the series of processes shown in FIG. 11 when it does not detect the start signal 40 for a predetermined time.

[0109] As shown in FIG. 11, when starting this series of processes, in the process of step S31, the processing device 21 switches to the second communication method. At this time, the processing device 21 switches the flag for determining the communication method of the second communication device 20 from the flag of the first communication method to the flag of the second communication method. As a result, the communication method in the second communication device 20 switches from the first communication method to the second communication method. In this way, the second communication device 20 switches the communication method from the first communication method to the second communication method.

[0110] In the next step S32, the processing device 21 determines whether there is data to be transmitted. At this time, the processing device 21 determines whether there is data to be transmitted based on whether the second communication device 20 needs to transmit the second data 42.

[0111] In step S32, when the processing device 21 determines that there is no data to be transmitted (step S32: NO), this series of processes ends. In step S32, when the processing device 21 determines that there is data to be transmitted (step S32: YES), the process proceeds to step S33. In the process of step S33, the processing device 21 executes offset time setting processing.

[0112] In the process of the next step S34, the processing device 21 transmits data in consideration of the offset time. At this time, the processing device 21 starts transmitting the second data 42 after the elapse of the offset time set in the process of step S33.

[0113] The processing device 21 that has transmitted the second data 42 ends this series of processes. Regarding the processing device 51 of the management device 50 as well, it executes the series of processes shown in FIG. 11 in the same manner as the processing device 11. The processing device 51 executes the series of processes shown in FIG. 11 when it does not sense the start signal 40 for a predetermined time.

[0114] As shown in FIG. 11, when starting this series of processes, in the process of step S31, the processing device 51 shifts to the second communication method. At this time, the processing device 51 switches the flag for determining the communication method of the management device 50 from the flag of the first communication method to the flag of the second communication method. As a result, the communication method in the management device 50 shifts from the first communication method to the second communication method. In this way, the management device 50 switches the communication method from the first communication method to the second communication method.

[0115] In the next step S32, the processing device 51 determines whether there is data to be transmitted. At this time, the processing device 51 determines whether there is data to be transmitted based on whether the management device 50 needs to transmit the third data 43.

[0116] In step S32, when the processing device 51 determines that there is no data to be transmitted (step S32: NO), this series of processes ends. In step S32, when the processing device 51 determines that there is data to be transmitted (step S32: YES), the process proceeds to step S33. In the process of step S33, the processing device 51 executes offset time setting processing.

[0117] In the process of the next step S34, the processing device 51 transmits data considering the offset time. At this time, the processing device 51 starts transmitting the third data 43 after the elapse of the offset time set in the process of step S33.

[0118] The processing device 51 that has transmitted the third data 43 ends this series of processes. <Processing when the management device 50 switches the communication method to the first communication method> FIG. 12 shows the flow of a series of processes when the management device 50 switches the communication method of the communication device to the first communication method. This series of processes is executed by the processing device 51 of the management device 50. The processing device 51 executes this series of processes after migrating the communication method to the second communication method in the process of step S31 in FIG. 11. This process corresponds to the process executed by the management device 50 shown in the lower part of FIG. 8.

[0119] As shown in FIG. 12, when starting this series of processes, in the process of step S41, the processing device 51 determines whether the state where data is not transmitted has continued for a certain period of time. That is, the processing device 51 determines whether the state where the first communication device 10, the second communication device 20, and the management device 50 do not transmit data by the second communication method has continued for a certain period of time.

[0120] In the process of step S41, when the processing device 51 determines that the state where data is not transmitted has not continued for a certain period of time (step S41: NO), the process of step S41 is repeated.

[0121] In the process of step S41, when the processing device 51 determines that the state where data is not transmitted continues for a certain period of time (step S41: YES), the process proceeds to step S42. In the process of step S42, the processing device 51 transmits a start signal 40.

[0122] In the process of the next step S43, the processing device 51 causes the communication method of the management device 50 to shift to the first communication method. At this time, the processing device 51 switches the flag for determining the communication method of the management device 50 from the flag of the second communication method to the flag of the first communication method. As a result, the communication method of the management device 50 shifts from the second communication method to the first communication method. In this way, the management device 50 returns the communication method from the second communication method to the first communication method.

[0123] The processing device 51 that has shifted the communication method to the first communication method ends this series of processes. Note that when the processing device 51 transmits the start signal 40 in step S42, as shown in the lower part of FIG. 8, the first communication device 10 and the second communication device 20 that have received the start signal 40 switch the flag for determining the communication method from the flag of the second communication method to the flag of the first communication method. As a result, the communication methods of the first communication device 10 and the second communication device 20 shift from the second communication method to the first communication method. In this way, the first communication device 10 and the second communication device 20 return the communication method from the second communication method to the first communication method.

[0124] <Operation of this Embodiment> In the communication network system 100 and the vehicle including the communication network system 100, the jamming device transmits a jamming signal according to the communication error situation. As a result, in the above communication network system 100 and the vehicle including the communication network system 100, the detection of the start signal 40 by the communication device is obstructed. And in the above communication network system 100 and the vehicle including the communication network system 100, the communication method of each communication device switches from the first communication method to the second communication method.

[0125] <Effect of this Embodiment> (1) In the first communication method, each communication device transmits data according to a predetermined order. On the other hand, in the second communication method, the communication device can transmit data regardless of the predetermined order. Therefore, the communication network system 100 and the vehicle equipped with the communication network system 100 can suppress communication errors occurring in a specific communication device.

[0126] (2) The jamming device acquires the status of communication errors in the communication network system 100. Then, the jamming device transmits a jamming signal based on the acquired status of communication errors. In the communication network system 100, the jamming device transmits a jamming signal based on the status of communication errors it has acquired. As a result, the communication network system 100 can switch the communication method of each communication device to the second communication method according to the status of communication errors.

[0127] (3) The communication network system 100 is mounted on a vehicle. The jamming device grasps the status of the vehicle. Then, the jamming device transmits a jamming signal based on the acquired status of communication errors and the grasped status of the vehicle.

[0128] In the second communication method, data can be transmitted regardless of the predetermined order. However, data cannot be transmitted when other communication devices are transmitting data. That is, in the second communication method, the opportunity for each communication device to transmit data is not guaranteed. Therefore, depending on the status of the vehicle, by switching the communication method of each communication device in the communication network system 100, there is a risk that a specific communication device will not be able to transmit data for a long period of time.

[0129] In the communication network system 100, the jamming device determines whether to transmit a jamming signal according to the status of the vehicle. As a result, the communication network system 100 can prioritize ensuring the opportunity to transmit data by not transmitting a jamming signal depending on the status of the vehicle.

[0130] (4) The jamming device acquires, as the communication error situation, information on the number of communication errors that occurred while each communication device transmitted data a predetermined number of times. In the communication network system 100, the jamming device acquires information on the occurrence frequency of communication errors in each communication device as the communication error situation. Thereby, the communication network system 100 can switch the communication method of each communication device to the second communication method according to the occurrence frequency of communication errors of each communication device.

[0131] (5) The jamming device transmits a jamming signal when the number of communication errors acquired as the communication error situation is equal to or greater than a preset value. In the communication network system 100, the jamming device transmits a jamming signal when the number of communication errors is equal to or greater than a preset value. Thereby, the communication network system 100 can switch the communication method to the second communication method when the occurrence frequency of communication errors is equal to or greater than a predetermined frequency.

[0132] (6) In the communication network system 100, a preset value is set for each communication device. The jamming device transmits a jamming signal when the number of communication errors for any one of the communication devices becomes equal to or greater than the preset value.

[0133] In the communication network system 100 described above, the jamming device transmits a jamming signal when the number of communication errors of any one of the communication devices is equal to or greater than the corresponding preset value. Thereby, the communication network system 100 can switch the communication method while closely monitoring the communication error situation for each communication device.

[0134] (7) When the grasped vehicle status is during autonomous driving, the jamming device does not transmit a jamming signal. When the vehicle is in autonomous driving, it is desirable that each communication device communicates using a first communication method in which the opportunity to transmit data is guaranteed. In the communication network system 100, the jamming device does not transmit a jamming signal when the vehicle is in autonomous driving. That is, in the communication network system 100 described above, the communication method is not switched to the second communication method when the vehicle is in autonomous driving. Thereby, the communication network system 100 can guarantee the communication opportunity for each communication device. That is, the communication network system 100 can suppress the situation where the execution of autonomous driving by the vehicle is inhibited by switching the communication method to the second communication method.

[0135] (8) When the grasped vehicle status is during fault diagnosis, the jamming device does not transmit a jamming signal. When the vehicle is in fault diagnosis, it is desirable that each communication device communicates using a first communication method in which the opportunity to transmit data is guaranteed. In the communication network system 100, the jamming device does not transmit a jamming signal when the vehicle is in fault diagnosis. That is, in the communication network system 100 described above, the communication method is not switched to the second communication method when the vehicle is in fault diagnosis. Thereby, the communication network system 100 can guarantee the communication opportunity for each communication device. That is, the communication network system 100 can suppress the situation where the execution of fault diagnosis by the vehicle is inhibited by switching the communication method to the second communication method.

[0136] (9) The interference device is applied to a communication network system 100 including a plurality of communication devices and a management device 50 that transmits a start signal 40 to the communication devices. After sensing the start signal 40, the plurality of communication devices communicate with each other using a first communication method in which each communication device transmits data in a predetermined order. Also, when the state of not sensing the start signal 40 continues for a predetermined time, the plurality of communication devices are set to switch the communication method to a second communication method in which data is transmitted when no other communication device is transmitting data, regardless of the predetermined order. The interference device transmits an interference signal that interferes with the sensing of the start signal 40 by the communication devices according to the communication error situation in the communication network system 100.

[0137] The interference device transmits an interference signal according to the communication error situation. As a result, in the communication network system 100 described above, the sensing of the start signal 40 by the communication devices is interfered with, and the communication method switches from the first communication method to the second communication method.

[0138] In the first communication method, each communication device transmits data according to a predetermined order. On the other hand, in the second communication method, the communication devices can transmit data regardless of the predetermined order.

[0139] Thereby, the interference device can suppress communication errors occurring in a specific communication device. (10) When the communication device switches the communication method from the first communication method to the second communication method, if there is data to be transmitted immediately after switching to the second communication method, the communication device sets an offset time from the moment of switching to the second communication method until the start of transmission of the data. Then, the communication device starts transmitting the data when the set offset time has elapsed.

[0140] In the second communication method, unlike the first communication method, the order in which each communication device transmits data is not determined. Therefore, immediately after switching to the second communication method, a plurality of communication devices may start transmitting data simultaneously, resulting in a collision between the data.

[0141] In the communication network system 100, the communication devices that have switched the communication method to the second communication method start transmitting data after the offset time set by each of them has elapsed. Thereby, the communication network system 100 can suppress the collision of data immediately after switching to the second communication method.

[0142] (11) When the communication device switches the communication method from the first communication method to the second communication method, if there is data to be transmitted immediately after switching to the second communication method, the communication device sets the offset time from the moment of switching the communication method to the second communication method until the start of transmission of the data. At this time, the communication device sets the offset time so that it becomes shorter as the capacity of the data to be transmitted is larger. Then, the communication device starts transmitting the data when the set offset time has elapsed.

[0143] In the communication network system 100, the communication devices that have switched the communication method to the second communication method start transmitting data after the offset time set by each of them has elapsed based on the capacity of the data that each itself is about to transmit. Thereby, when the communication device switches the communication method to the second communication method, the communication network system 100 can preferentially transmit data with a large capacity while suppressing the collision of data.

[0144] (12) Each communication device has a priority order set in advance. When the communication device switches the communication method from the first communication method to the second communication method, if there is data to be transmitted immediately after switching to the second communication method, the communication device sets the offset time from the moment of switching the communication method to the second communication method until the start of transmission of the data. At this time, the communication device sets the offset time so that it becomes shorter as the priority order is higher. The communication device starts transmitting the data when the set offset time has elapsed.

[0145] In the communication network system 100, a communication device that has switched its communication method to the second communication method starts transmitting data after the offset time set by each of them has elapsed based on a predetermined priority order. As a result, when a communication device switches its communication method to the second communication method, the communication network system 100 can suppress collisions between data and enable a communication device with a higher priority to transmit data preferentially.

[0146] (13) The program is applied to a jamming device of the communication network system 100. The communication network system 100 includes a plurality of communication devices and a management device 50 that transmits a start signal 40. After sensing the start signal 40, the plurality of communication devices communicate with each other using a first communication method in which they transmit their respective data in a predetermined order. Also, when the state of not sensing the start signal 40 continues for a predetermined time, the plurality of communication devices are set to switch their communication method to a second communication method in which they transmit data when no other communication device is transmitting data, regardless of the predetermined order. The program causes the jamming device to transmit a jamming signal that interferes with the sensing of the start signal 40 by the communication device based on the communication error situation in the communication network system 100.

[0147] The program causes the jamming device to transmit a jamming signal according to the communication error situation. As a result, in the communication network system 100 described above, the sensing of the start signal 40 by the communication device is interfered with, and the communication method is switched from the first communication method to the second communication method.

[0148] In the first communication method, each communication device transmits data in a predetermined order. On the other hand, in the second communication method, the communication device can transmit data regardless of the predetermined order.

[0149] As a result, the program can suppress communication errors occurring in a specific communication device. In the above-described embodiment, the program is stored in the storage device 12 of the first communication device 10. This program may be provided in a state recorded on a recording medium. Examples of the recording medium on which the program is recorded include memories such as USB memories, SSDs, and SD cards, and CD-ROMs, optical discs, and the like.

[0150] (14) The communication network system 100 is composed of a plurality of communication devices. The communication network system 100 includes a management device 50 that transmits a start signal 40 and a jamming device that transmits a jamming signal that interferes with the detection of the start signal 40 by the communication devices. In the communication network system 100, after a plurality of communication devices detect the start signal 40, they communicate with each other using a first communication method in which each transmits its data in a predetermined order. The communication method is a communication method in such a communication network system 100. The communication method includes a step (step S104) in which the jamming device transmits a jamming signal based on the communication error situation in the communication network system 100. The communication method includes a step (step S31) of switching the communication method to a second communication method in which, when the state in which a plurality of communication devices do not detect the start signal 40 continues for a predetermined time, each communication device transmits data regardless of the predetermined order when no other communication device is transmitting data.

[0151] In the communication network system 100, the communication method causes the jamming device to transmit a jamming signal according to the communication error situation. As a result, in the above-described communication network system 100, the detection of the start signal 40 by the communication devices is interfered with, and the communication method is switched from the first communication method to the second communication method.

[0152] In the first communication method, each communication device transmits data according to a predetermined order. On the other hand, in the second communication method, the communication devices can transmit data regardless of the predetermined order.

[0153] As a result, the communication method can suppress communication errors occurring in a specific communication device. <Modification Example> This embodiment can be implemented with the following modifications. This embodiment and the following modification examples can be implemented in combination with each other within a technically non - conflicting range.

[0154] · In this embodiment, the management device 50 transmits the third data 43. The management device 50 does not necessarily also serve as a communication device for transmitting data. That is, the management device 50 only needs to be a device that transmits the start signal 40, and does not necessarily also serve as a communication device that transmits the third data 43 using the start signal 40 as a signal in the first communication method. In this case, the management device 50 also does not necessarily serve as a communication device that transmits the third data 43 in the second communication method.

[0155] · In this embodiment, the first communication device 10 transmits the first data 41. On the other hand, the interference device does not necessarily also serve as a communication device for transmitting data. That is, the first communication device 10 functioning as an interference device in this embodiment only needs to be a device that transmits an interference signal, and does not necessarily also serve as a communication device that transmits the first data 41 using the start signal 40 as a signal in the first communication method. At this time, the first communication device 10 also does not necessarily serve as a communication device that transmits the first data 41 in the second communication method.

[0156] · In this embodiment, the communication devices in the communication network system 100 are wired - connected through the communication bus 30. On the other hand, the communication devices in the communication network system 100 may also be wirelessly connected.

[0157] · In this embodiment, the first communication device 10 acquires the communication error status for all communication devices in the communication network system 100. On the other hand, the first communication device 10 may also acquire the communication error status only for a specific communication device.

[0158] · In this embodiment, the default value is set for each communication device. On the other hand, in the communication network system 100, the default value may be common among a plurality of communication devices. In the communication network system 100, the default value may be common to all communication devices.

[0159] · In this embodiment, the first communication device 10 acquires the communication error situation for each communication device in the communication network system 100. On the other hand, the first communication device 10 may acquire the communication error situation of the entire communication network system 100.

[0160] In this case, the jamming device acquires, as the communication error situation, information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system 100. In the communication network system 100, the jamming device acquires, as the communication error situation, information on the occurrence frequency of communication errors in the entire communication network system 100. Thereby, the communication network system 100 can switch the communication method of the communication device to the second communication method according to the occurrence frequency of communication errors in the data transmitted in the communication network system 100.

[0161] At this time, the default value is provided not for each communication device but for the entire communication network system 100 as one. · In this embodiment, the first communication device 10 transmits a jamming signal based on the communication error situation it has acquired itself. On the other hand, the first communication device 10 may transmit a jamming signal not based on the communication error situation it has acquired itself but based on a request from another communication device that has acquired the communication error situation.

[0162] FIG. 13 shows a specific example of communication when the first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the first modification example switch the communication method to the second communication method. The first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the first modification example execute the communication shown in FIG. 13 instead of the communication shown in FIG. 8.

[0163] The communication shown in FIG. 13 is executed when two conditions similar to those in FIG. 8 are satisfied. When the two conditions are satisfied, as shown in the upper part of FIG. 13, the second communication device 20 transmits a jamming request signal toward the first communication device 10 which is a jamming device. The jamming request signal is a signal that requests the jamming device to transmit a jamming signal. Thus, in this example, in the first modification, the second communication device 20 serves as a jamming request device that transmits a jamming request signal according to the communication error situation.

[0164] As shown in the upper part of FIG. 13, after receiving the jamming request signal, the first communication device 10 transmits a jamming signal at the timing when the management device 50 transmits the start signal 40. Thereby, the first communication device 10, the second communication device 20, and the management device 50 stop sensing the start signal 40.

[0165] The communication mode after the first communication device 10 transmits the jamming signal is the same as that in FIG. 8. In the first modification, since the second communication device 20 transmits a jamming request signal as necessary, it acquires the communication error situation in the communication network system 100. At this time, the second communication device 20 acquires information on the number of communication errors that occurred while each communication device transmitted data a predetermined number of times, as the communication error situation, in the same manner as the first communication device 10 in the above-described embodiment. Also, in the first modification, a default value is set for each communication device in the same manner as in the above-described embodiment.

[0166] FIG. 14 shows a series of processes executed when the second communication device 20 transmits a jamming request signal. This series of processes is executed by the processing device 21 of the second communication device 20. This series of processes is executed when the second communication device 20 acquires information on the number of communication errors that occurred while transmitting data a predetermined number of times for any one of the first communication device 10, the second communication device 20 itself, and the management device 50.

[0167] As shown in FIG. 14, when starting this series of processes, in the process of step S111, the processing device 21 determines whether the number of communication errors in the communication device that has acquired information is equal to or greater than a preset value. This process is the same as the process executed by the processing device 11 in step S101 of FIG. 10.

[0168] In the process of step S111, when the processing device 21 determines that the number of communication errors is not equal to or greater than the preset value (step S111: NO), it ends this series of processes. In the process of step S111, when the processing device 21 determines that the number of communication errors is equal to or greater than the preset value (step S111: YES), it advances the process to step S112.

[0169] In the process of step S112, the processing device 21 grasps the situation of the vehicle. This process is the same as the process executed by the processing device 11 in step S102 of FIG. 10. In the next process of step S113, the processing device 21 determines whether the communication device in the communication network system 100 can migrate to the second communication method. This process is the same as the process executed by the processing device 11 in step S103 of FIG. 10. Therefore, for example, when the situation of the vehicle is during autonomous driving, the processing device 21 determines that the communication device cannot migrate to the second communication method. Also, for example, when the situation of the vehicle is during fault diagnosis, the processing device 21 determines that the communication device cannot migrate to the second communication method.

[0170] In the process of step S113, when the processing device 21 determines that the communication device cannot migrate to the second communication method (step S113: NO), it ends this series of processes. In the process of step S113, when the processing device 21 determines that the communication device can migrate to the second communication method (step S113: YES), it advances the process to step S114.

[0171] In the process of step S114, the processing device 21 transmits an interference request signal. At this time, the processing device 21 transmits the interference request signal according to the first communication method. This process corresponds to the process executed by the second communication device 20 in the upper part of FIG. 13. In this way, the processing device 21 transmits an interference request signal based on the acquired communication error situation and the grasped vehicle situation.

[0172] Upon receiving the interference request signal, the first communication device 10 transmits an interference signal in response to the interference request signal instead of the series of processes shown in FIG. 10. As described above, the communication network system 100 of the first modification example includes an interference request device that transmits an interference request signal for requesting the interference device to transmit an interference signal. The interference request device acquires the communication error situation in the communication network system 100. Then, the interference request device transmits an interference request signal based on the acquired communication error situation. The interference device transmits an interference signal when it receives the interference request signal.

[0173] In the communication network system 100 of the first modification example, the interference request device causes the interference device to transmit an interference signal according to the acquired communication error situation. Thereby, the communication network system 100 of the first modification example can switch the communication method of the communication device to the second communication method according to the communication error situation.

[0174] The communication network system 100 of the first modification example is mounted on a vehicle. The interference request device grasps the vehicle situation. The interference request device transmits an interference request signal based on the acquired communication error situation and the grasped vehicle situation.

[0175] In the communication network system 100 of the first modification example, the interference request device determines whether to transmit an interference request signal according to the vehicle situation. Thereby, the communication network system can prioritize ensuring the data transmission opportunity by not transmitting the interference request signal depending on the vehicle situation.

[0176] In the communication network system 100 of the first modification example, the interference request device acquires, as the communication error situation, information on the number of communication errors that occurred while the communication device transmitted data a predetermined number of times.

[0177] In the communication network system 100 of the first modification example, the interference request device acquires information on the occurrence frequency of communication errors in the communication device as the communication error situation. Thereby, the communication network system 100 of the first modification example can switch the communication method of the communication device to the second communication method according to the occurrence frequency of communication errors of the communication device.

[0178] In the communication network system 100 of the first modification example, the interference request device transmits an interference request signal when the number of communication errors acquired as the communication error situation is equal to or greater than a predetermined value. In the communication network system 100 of the first modification example, the interference request device transmits an interference request signal when the number of communication errors is equal to or greater than a predetermined value. Thereby, the communication network system 100 of the first modification example can switch the communication method to the second communication method when the occurrence frequency of communication errors is equal to or higher than a predetermined frequency.

[0179] Also in the first modification example, the predetermined value is set for each communication device. The interference request device transmits an interference request signal when the number of communication errors for any one of the communication devices becomes equal to or greater than the predetermined value.

[0180] In the communication network system 100 of the first modification example, the interference request device transmits an interference request signal when the number of communication errors of any one of the communication devices is equal to or greater than the corresponding predetermined value. Thereby, the communication network system 100 of the first modification example can switch the communication method to the second communication method while finely monitoring the communication error situation for each communication device.

[0181] In the communication network system 100 of the first modification example, when the situation of the vehicle grasped by the interference request device indicates that the vehicle is in the process of automatic driving, the interference request signal is not transmitted. That is, in the communication network system 100 of the first modification example, when the vehicle is in the process of automatic driving, the communication method is not switched to the second communication method. Thereby, the communication network system 100 of the first modification example can guarantee the communication opportunity for each communication device. That is, the communication network system 100 of the first modification example can suppress the situation where the execution of the automatic driving by the vehicle is inhibited by switching the communication method to the second communication method.

[0182] In the communication network system 100 of the first modification example, when the situation of the vehicle grasped by the interference request device indicates that the vehicle is in the process of fault diagnosis, the interference request signal is not transmitted. That is, in the communication network system 100 of the first modification example, when the vehicle is in the process of fault diagnosis, the communication method is not switched to the second communication method. Thereby, the communication network system 100 of the first modification example can guarantee the communication opportunity for each communication device. That is, the communication network system 100 of the first modification example can suppress the situation where the execution of the fault diagnosis by the vehicle is inhibited by switching the communication method to the second communication method.

[0183] · In the first modification example, the second communication device 20 acquires the communication error situation for all the communication devices in the communication network system 100. On the other hand, the second communication device 20 may acquire the communication error situation only for a specific communication device.

[0184] · In the first modification example, the second communication device 20 acquires the communication error situation for each communication device in the communication network system 100. On the other hand, the second communication device 20 may acquire the communication error situation for the entire communication network system 100.

[0185] In this case, the interference request device acquires information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system 100 of the first modification example, as the communication error situation. In the communication network system 100 of the first modification example, the interference request device acquires information on the occurrence frequency of communication errors in the entire communication network system 100, as the communication error situation. Thereby, the communication network system 100 of the first modification example can switch the communication method of the communication device to the second communication method according to the occurrence frequency of communication errors in the data transmitted by the communication network system 100.

[0186] ·In the first modification example, the second communication device 20, which is the interference request device, transmits an interference request signal based on the acquired error situation and the grasped vehicle situation. On the other hand, the second communication device 20 may transmit an interference request signal based only on the acquired error situation without grasping the vehicle situation. In this case, the first communication device 10, which is the interference device that received the interference request signal, transmits an interference signal based on the vehicle situation after grasping the vehicle situation.

[0187] FIG. 15 shows a specific example of communication when the first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the second modification example switch the communication method to the second communication method. The first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the second modification example execute the communication shown in FIG. 15 instead of the communication shown in FIG. 8.

[0188] In the communication shown in FIG. 15, when the number of communication errors that occurred while any communication device in the communication network system 100 transmitted data a predetermined number of times becomes equal to or greater than a predetermined value, the second communication device 20 transmits an interference request signal toward the first communication device 10.

[0189] Then, when the first communication device 10 that has received the interference request signal can shift to the second communication method, it transmits an interference signal at the timing when the management device 50 transmits the start signal 40. As a result, the first communication device 10, the second communication device 20, and the management device 50 no longer sense the start signal 40.

[0190] The communication mode after the first communication device 10 transmits the interference signal is the same as that in FIG. 8. FIG. 16 shows a series of processes executed when the second communication device 20 transmits an interference request signal. This series of processes is executed by the processing device 21 of the second communication device 20. This series of processes is executed when the second communication device 20 acquires information on the number of communication errors that occurred during the transmission of data a predetermined number of times for any one of the first communication device 10, the second communication device 20 itself, and the management device 50.

[0191] As shown in FIG. 16, when starting this series of processes, in the process of step S121, the processing device 21 determines whether the number of communication errors in the communication device that acquired the information is equal to or greater than a predetermined value. This process is the same as the process executed by the processing device 11 in step S101 of FIG. 10.

[0192] In the process of step S121, when the processing device 21 determines that the number of communication errors is not equal to or greater than the predetermined value (step S121: NO), it ends this series of processes. In the process of step S121, when the processing device 21 determines that the number of communication errors is equal to or greater than the predetermined value (step S121: YES), it advances the process to step S122. In the process of step S122, the processing device 21 transmits an interference request signal. At this time, the processing device 21 transmits the interference request signal according to the first communication method. This process corresponds to the process executed by the second communication device 20 in the upper part of FIG. 15.

[0193] FIG. 17 shows a series of processing flows when the first communication device 10 transmits an interference signal. This series of processing is executed by the processing device 11 of the first communication device 10. The processing device 11 transmits an interference signal by executing the series of processing shown in FIG. 17 instead of the series of flows shown in FIG. 10. This series of processing is executed when the first communication device 10 receives an interference request signal.

[0194] As shown in FIG. 17, when starting this series of processing, in the processing of step S131, the processing device 11 grasps the situation of the vehicle. This processing is the same as the processing of step S102 in FIG. 10.

[0195] In the processing of the next step S132, the processing device 11 determines whether the communication device in the communication network system 100 can shift to the second communication method. This processing is the same as the processing of step S103 in FIG. 10.

[0196] In the processing of step S132, when the processing device 11 determines that the communication device cannot shift to the second communication method (step S132: NO), this series of processing ends. In the processing of step S132, when the processing device 11 determines that the communication device can shift to the second communication method (step S132: YES), the processing proceeds to step S133. In the processing of step S133, the processing device 11 transmits an interference signal. This processing corresponds to the processing executed by the first communication device 10 in the upper part of FIG. 15.

[0197] The communication network system 100 of the second modification example is mounted on a vehicle. The interference device grasps the situation of the vehicle. When receiving an interference request signal, the interference device transmits an interference signal based on the grasped situation of the vehicle.

[0198] In the communication network system 100 of the second modification example, when the interference device receives an interference request signal, it determines whether to transmit an interference signal according to the situation of the vehicle. Thereby, the communication network system 100 of the second modification example can prioritize ensuring the data transmission opportunity by not transmitting an interference signal depending on the situation of the vehicle.

[0199] ·In the above embodiment, the first communication device 10 in the communication network system 100 switches the communication method of the communication device to the second communication method by transmitting an interference signal. On the other hand, the communication method of the communication device may be switched to the second communication method by the management device 50 in the communication network system 100 stopping the transmission of the start signal 40.

[0200] FIG. 18 shows a specific example of communication when the first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the third modification example switch the communication method to the second communication method. The first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the third modification example execute the communication shown in FIG. 18 instead of the communication mode shown in FIG. 8.

[0201] The communication shown in FIG. 18 is executed when two conditions similar to those in FIG. 8 are satisfied. When the two conditions are satisfied, as shown in the upper part of FIG. 18, the management device 50 stops transmitting the start signal 40. Thereby, the first communication device 10, the second communication device 20, and the management device 50 no longer sense the start signal 40.

[0202] As shown in the middle part of FIG. 8, when the state where the first communication device 10 and the second communication device 20 do not sense the start signal continues for a predetermined time with the management device 50, they shift to the second communication method. In this way, each communication device in the communication network system 100 of the third modification example switches the communication method from the first communication method to the second communication method.

[0203] The communication mode after the communication device switches to the second communication method is the same as that in FIG. 8. Note that in the third modification example, the first communication device 10 does not need to be a jamming device. Therefore, in the third modification example, the first communication device 10 does not execute the series of processes shown in FIG. 10.

[0204] In the third modification example, since the management device 50 stops transmitting the start signal 40 as necessary, it acquires the communication error status in the communication network system 100 instead of the first communication device 10. At this time, similar to the first communication device 10 of the present embodiment, the management device 50 acquires, as the communication error status, information on the number of communication errors that occurred while each communication device transmitted data a predetermined number of times. Also, in the third modification example, similar to the present embodiment, a default value is set for each communication device.

[0205] FIG. 19 shows a series of processes executed when the management device 50 stops transmitting the start signal 40. The program stored in the storage device 52 of the management device 50 includes a program for controlling the communication methods of a plurality of communication devices in the communication network system 100 of the third modification example. This series of processes is executed when the processing device 51 of the management device 50 performs processing according to the program stored in the storage device 52. This series of processes is executed when the management device 50 acquires information on the number of communication errors that occurred while transmitting data a predetermined number of times for any one of the first communication device 10, the second communication device 20, and the management device 50 itself.

[0206] As shown in FIG. 19, when starting this series of processes, in the process of step S141, the processing device 51 determines whether the number of communication errors in the communication device from which the information was acquired is equal to or greater than the default value. This process is the same as the process executed by the processing device 11 in step S101 of FIG. 10.

[0207] In the process of step S141, when the processing device 51 determines that the number of communication errors is not equal to or greater than the default value (step S141: NO), this series of processes ends. In the process of step S141, when the processing device 51 determines that the number of communication errors is equal to or greater than a preset value (step S141: YES), the process proceeds to step S142.

[0208] In the process of step S142, the processing device 51 grasps the situation of the vehicle. This process is the same as the process executed by the processing device 11 in step S102 of FIG. 10. In the process of the next step S143, the processing device 51 determines whether the communication device in the communication network system 100 of the third modification example can shift to the second communication method. This process is the same as the process executed by the processing device 11 in step S103 of FIG. 10. Therefore, for example, the processing device 51 determines that the communication device cannot shift to the second communication method when the situation of the vehicle is in the middle of automatic driving. Also, for example, the processing device 51 determines that the communication device cannot shift to the second communication method when the situation of the vehicle is in the middle of fault diagnosis.

[0209] In the process of step S143, when the processing device 51 determines that the communication device cannot shift to the second communication method (step S143: NO), this series of processes ends. In the process of step S143, when the processing device 51 determines that the communication device can shift to the second communication method (step S143: YES), the process proceeds to step S144. In the process of step S144, the processing device 51 stops transmitting the start signal 40. This process corresponds to the process executed by the management device 50 in the upper part of FIG. 18. In this way, the processing device 51 stops transmitting the start signal 40 based on the acquired communication error situation and the grasped vehicle situation.

[0210] The communication network system 100 of the third modification example is composed of a plurality of communication devices. The communication network system 100 of the third modification example and the vehicle equipped with the communication network system 100 of the third modification example include a management device 50 that transmits a start signal 40 to the plurality of communication devices. After sensing the start signal 40, the plurality of communication devices communicate with each other using a first communication method in which each communication device transmits data in a predetermined order. The management device 50 stops transmitting the start signal 40 according to the communication error situation in the communication network system 100 of the third modification example. When the state of not sensing the start signal 40 continues for a predetermined time, the plurality of communication devices switch the communication method to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order.

[0211] In the communication network system 100 of the third modification example and the vehicle equipped with the communication network system 100, the management device 50 stops transmitting the start signal 40 according to the communication error situation. Thereby, in the communication network system 100 of the third modification example and the vehicle equipped with the communication network system 100, the communication method switches from the first communication method to the second communication method.

[0212] In the first communication method, each communication device transmits data according to a predetermined order. On the other hand, in the second communication method, the communication device can transmit data regardless of the predetermined order. Thereby, the communication network system 100 of the third modification example and the vehicle equipped with the communication network system 100 can suppress communication errors occurring in a specific communication device.

[0213] The management device 50 acquires the communication error situation in the communication network system 100 of the third modification example. The management device 50 stops transmitting the start signal 40 based on the acquired communication error situation.

[0214] In the communication network system 100 of the third modification example, the management device 50 stops transmitting the start signal based on the communication error situation it has acquired. As a result, the communication network system 100 of the third modification example can switch the communication method of each communication device to the second communication method in response to the communication error situation.

[0215] The communication network system 100 of the third modification example is mounted on a vehicle. The management device 50 grasps the situation of the vehicle. The management device 50 stops transmitting the start signal 40 based on the acquired communication error situation and the grasped vehicle situation.

[0216] In the communication network system 100 of the third modification example, the management device 50 determines whether to stop transmitting the start signal according to the situation of the vehicle. As a result, the communication network system 100 of the third modification example can prioritize ensuring the data transmission opportunity by not stopping the start signal 40 according to the vehicle situation.

[0217] In the communication network system 100 of the third modification example, the management device 50 acquires information on the number of communication errors that occurred while the communication device transmitted data a predetermined number of times as the communication error situation. In the communication network system 100 of the third modification example, the management device 50 acquires information on the occurrence frequency of communication errors in each communication device as the communication error situation. As a result, the communication network system 100 of the third modification example can switch the communication method of the communication device to the second communication method according to the occurrence frequency of the communication error of the communication device.

[0218] In the communication network system 100 of the third modification example, the management device 50 stops transmitting the start signal 40 when the number of communication errors acquired as the communication error situation is equal to or greater than a predetermined value. As a result, the communication network system 100 of the third modification example can switch the communication method to the second communication method when the occurrence frequency of communication errors is equal to or greater than a predetermined frequency.

[0219] Predetermined values are set for each communication device. In the communication network system 100 of the third modification example, when the number of communication errors for any communication device reaches or exceeds the predetermined value, the management device 50 stops transmitting the start signal 40.

[0220] In the communication network system 100 of the third modification example, when the number of communication errors of any communication device is equal to or greater than the corresponding predetermined value, the management device 50 stops transmitting the start signal. As a result, the communication network system 100 of the third modification example can switch the communication method to the second communication method while closely monitoring the communication error status for each communication device.

[0221] In the communication network system 100 of the third modification example, when the management device 50 determines that the vehicle is in the process of autonomous driving, it does not stop transmitting the start signal. That is, in the communication network system 100 of the third modification example, the communication method is not switched to the second communication method when the vehicle is in autonomous driving. As a result, the communication network system 100 of the third modification example can ensure the communication opportunity for each communication device. That is, the communication network system 100 of the third modification example can prevent the execution of autonomous driving by the vehicle from being hindered by switching the communication method to the second communication method.

[0222] In the communication network system 100 of the third modification example, when the management device 50 determines that the vehicle is in the process of fault diagnosis, it does not stop transmitting the start signal 40. That is, in the communication network system 100 of the third modification example, the communication method is not switched to the second communication method when the vehicle is in fault diagnosis. As a result, the communication network system 100 of the third modification example can ensure the communication opportunity for each communication device. That is, the communication network system 100 of the third modification example can prevent the execution of fault diagnosis by the vehicle from being hindered by switching the communication method to the second communication method.

[0223] The management device 50 transmits a start signal 40 in the communication network system 100 of the third modification example configured by a plurality of communication devices. After sensing the start signal 40, the plurality of communication devices communicate with each other using a first communication method in which each communication device transmits data in a predetermined order. On the other hand, when the state of not sensing the start signal 40 continues for a predetermined time, the communication method is set to switch to a second communication method in which data is transmitted when no other communication device is transmitting data, regardless of the predetermined order. The management device 50 stops transmitting the start signal 40 according to the communication error situation in the communication network system 100 of the third modification example.

[0224] The management device 50 stops transmitting the start signal 40 according to the communication error situation. As a result, in the communication network system 100 of the third modification example, the communication method switches from the first communication method to the second communication method.

[0225] In the first communication method, each communication device transmits data according to a predetermined order. On the other hand, in the second communication method, the communication device can transmit data regardless of the predetermined order.

[0226] Thereby, the management device 50 can suppress communication errors occurring in a specific communication device. The program is a program applied to the management device 50 that transmits the start signal 40 in the communication network system 100 of the third modification example configured by a plurality of communication devices. After sensing the start signal 40, the plurality of communication devices communicate with each other using a first communication method in which each transmits its own data in a predetermined order. On the other hand, when the state of not sensing the start signal 40 continues for a predetermined time, the communication method is set to switch to a second communication method in which data is transmitted when no other communication device is transmitting data, regardless of the predetermined order. The program causes the management device 50 to stop transmitting the start signal 40 based on the communication error situation in the communication network system 100 of the third modification example.

[0227] The program causes the management device 50 to stop transmitting the start signal 40 according to the communication error situation. As a result, in the communication network system 100 of the third modification example, the communication method switches from the first communication method to the second communication method.

[0228] In the first communication method, each communication device transmits data in a predetermined order. On the other hand, in the second communication method, the communication device can transmit data regardless of the predetermined order.

[0229] As a result, the program can suppress communication errors occurring in a specific communication device. In the above embodiment, the program is stored in the storage device 52 of the management device 50. This program may be provided in a state recorded on a recording medium. Examples of the recording medium on which the program is recorded include memories such as USB memories, SSDs, SD cards, and CD-ROMs, optical discs, and the like.

[0230] The communication network system 100 of the third modification example is composed of a plurality of communication devices. The communication network system 100 of the third modification example includes a management device 50 that transmits the start signal 40. After detecting the start signal 40, the plurality of communication devices communicate with each other using the first communication method in which each transmits its data in a predetermined order. The communication method is the communication method in such a communication network system of the third modification example. The communication method includes a step (step S144) in which the management device 50 stops transmitting the start signal 40 based on the communication error situation in the communication network system 100 of the third modification example. The communication method includes a step (step S31) of switching the communication method to the second communication method in which, when the state of not detecting the start signal 40 continues for a predetermined time and when no other communication device is transmitting data, a communication device transmits data regardless of the predetermined order.

[0231] In the communication network system 100 of the third modification example, the communication method stops the transmission of the start signal 40 to the management device 50 according to the communication error situation. As a result, in the communication network system 100 of the third modification example, the communication method switches from the first communication method to the second communication method.

[0232] In the first communication method, each communication device transmits data according to a predetermined order. On the other hand, in the second communication method, the communication device can transmit data regardless of the predetermined order.

[0233] As a result, the communication method can suppress communication errors occurring in a specific communication device. · In the third modification example, the management device 50 acquires the communication error situation for all communication devices in the communication network system 100. On the other hand, the management device 50 may acquire the communication error situation only for a specific communication device.

[0234] · In the third modification example, the management device 50 acquires the communication error situation for each communication device in the communication network system 100. On the other hand, the management device 50 may acquire the communication error situation for the entire communication network system 100.

[0235] In this case, the management device 50 acquires, as the communication error situation, information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system 100 of the third modification example.

[0236] In this case, in the communication network system 100 of the third modification example, the management device 50 acquires, as the communication error situation, information on the occurrence frequency of communication errors in the entire communication network system 100 of the third modification example. As a result, the communication network system 100 of the third modification example can switch the communication method of the communication device to the second communication method according to the occurrence frequency of communication errors in the data transmitted in the communication network system 100 of the third modification example.

[0237] · In the third modification example, the management device 50 stops transmitting the start signal 40 based on the communication error situation it has acquired itself. On the other hand, instead of the management device 50 acquiring the communication error situation itself, it may stop transmitting the start signal 40 based on a request from another communication device that has acquired the communication error situation.

[0238] FIG. 20 shows a specific example of communication when the first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the fourth modification example switch the communication method to the second communication method. The first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the fourth modification example execute the communication shown in FIG. 20 instead of the communication mode shown in FIG. 8.

[0239] The communication shown in FIG. 20 is executed when two conditions similar to those in FIG. 8 are satisfied. When the two conditions are satisfied, as shown in the upper part of FIG. 20, the first communication device 10 transmits a stop request signal toward the management device 50. The stop request signal is a signal that requests the management device 50 to stop transmitting the start signal 40. Thus, in this example, in the fourth modification example, the first communication device 10 serves as a stop request device that transmits a stop request signal according to the communication error situation.

[0240] As shown in the upper part of FIG. 20, after receiving the stop request signal, the management device 50 stops transmitting the start signal 40. As a result, the first communication device 10, the second communication device 20, and the management device 50 no longer sense the start signal 40.

[0241] As shown in the middle part of FIG. 20, when the state where the first communication device 10, the second communication device 20, and the management device 50 do not sense the start signal continues for a predetermined time, they shift to the second communication method. In this way, the communication devices in the communication network system 100 of the fourth modification example switch the communication method to the second communication method.

[0242] The communication mode after the communication device switches to the second communication method is the same as that in FIG. 8. In the fourth modification example, similar to the third modification example, the first communication device 10 does not need to be a jamming device. Therefore, in the fourth modification example, the first communication device 10 does not execute the series of processes shown in FIG. 10.

[0243] In the fourth modification example, since the first communication device 10 transmits a stop request signal as needed, it acquires the communication error situation in the communication network system 100. At this time, similar to the above-described embodiment, the first communication device 10 acquires information on the number of communication errors that occurred while each communication device transmitted data a predetermined number of times as the communication error situation. Also, in the fourth modification example, similar to the above-described embodiment, a default value is set for each communication device.

[0244] FIG. 21 shows a series of processes executed when the first communication device 10 transmits a stop request signal. This series of processes is executed by the processing device 11 of the first communication device 10. This series of processes is executed when the first communication device 10 acquires information on the number of communication errors that occurred while transmitting data a predetermined number of times for any one of the first communication device 10 itself, the second communication device 20, and the management device 50.

[0245] As shown in FIG. 21, when starting this series of processes, in the process of step S151, the processing device 11 determines whether the number of communication errors in the communication device for which information has been acquired is equal to or greater than the default value. This process is the same as the process of step S101 in FIG. 10.

[0246] In the process of step S151, when the processing device 11 determines that the number of communication errors is not equal to or greater than the default value (step S151: NO), it ends this series of processes. In the process of step S151, when the processing device 21 determines that the number of communication errors is equal to or greater than the default value (step S151: YES), it advances the process to step S152.

[0247] In the process of step S152, the processing device 11 grasps the situation of the vehicle. This process is the same as the process of step S102 in FIG. 10. In the process of the next step S153, the processing device 11 determines whether the communication device in the communication network system 100 of the fourth modification example can shift to the second communication method. This process is the same as the process of step S103 in FIG. 10. Therefore, for example, when the situation of the vehicle is in the middle of autonomous driving, the processing device 11 determines that the communication device cannot shift to the second communication method. Also, for example, when the situation of the vehicle is in the middle of fault diagnosis, the processing device 21 determines that the communication device cannot shift to the second communication method.

[0248] In the process of step S153, when the processing device 11 determines that the communication device cannot shift to the second communication method (step S153: NO), this series of processes is terminated. In the process of step S153, when the processing device 11 determines that the communication device can shift to the second communication method (step S153: YES), the process proceeds to step S154. In the process of step S154, the processing device 11 transmits a stop request signal. At this time, the processing device 11 transmits the stop request signal according to the first communication method. This process corresponds to the process executed by the first communication device 10 in the upper part of FIG. 20. In this way, the processing device 11 transmits a stop request signal based on the acquired communication error situation and the grasped vehicle situation.

[0249] The management device 50 that has received the stop request signal stops transmitting the start signal 40 in response to the stop request signal. The communication network system 100 of the fourth modification example includes a stop request device that transmits a stop request signal requesting the management device 50 to stop transmitting the start signal 40. The stop request device acquires the communication error situation in the communication network system 100 of the fourth modification example. The stop request device transmits a stop request signal based on the acquired communication error situation. The management device 50 stops transmitting the start signal 40 when it receives the stop request signal.

[0250] In the communication network system 100 of the fourth modification example, the stop request device stops transmitting the start signal 40 to the management device 50 according to the acquired communication error situation. Thereby, the communication network system 100 of the fourth modification example can switch the communication method of the communication device to the second communication method according to the communication error situation.

[0251] The communication network system 100 of the fourth modification example is mounted on a vehicle. The stop request device grasps the situation of the vehicle. The stop request device transmits a stop request signal based on the acquired communication error situation and the grasped vehicle situation.

[0252] In the communication network system 100 of the fourth modification example, the stop request device determines whether to transmit a stop request signal according to the situation of the vehicle. Thereby, the communication network system 100 of the fourth modification example can prioritize ensuring the data transmission opportunity by not transmitting the stop request signal depending on the situation of the vehicle.

[0253] In the communication network system 100 of the fourth modification example, the stop request device acquires information on the number of communication errors that occurred while each communication device transmitted data a predetermined number of times as the communication error situation. In the communication network system 100 of the fourth modification example, the stop request device acquires information on the occurrence frequency of communication errors in each communication device as the communication error situation. Thereby, the communication network system 100 of the fourth modification example can switch the communication method of the communication device to the second communication method according to the occurrence frequency of communication errors in each communication device.

[0254] In the communication network system 100 of the fourth modification example, when the number of communication errors acquired as the communication error situation is equal to or greater than a preset value, the stop request device transmits a stop request signal. In the communication network system 100 of the fourth modification example, when the number of communication errors is equal to or greater than a preset value, the stop request device transmits a stop request signal. Thereby, the communication network system 100 of the fourth modification example can switch the communication method to the second communication method when the occurrence frequency of communication errors is equal to or greater than a predetermined frequency.

[0255] The preset value is set for each communication device. In the communication network system 100 of the fourth modification example, when the number of communication errors for any one of the communication devices becomes equal to or greater than the preset value, the stop request device transmits a stop request signal. In the communication network system 100 of the fourth modification example, when the number of communication errors of any one of the communication devices is equal to or greater than the corresponding preset value, the stop request device transmits a stop request signal. Thereby, the communication network system 100 of the fourth modification example can switch the communication method to the second communication method while carefully monitoring the communication error situation for each communication device.

[0256] In the communication network system 100 of the fourth modification example, when the grasped vehicle situation is during automatic driving, the stop request device does not transmit a stop request signal. That is, in the communication network system 100 of the fourth modification example, the communication method is not switched to the second communication method when the vehicle is in automatic driving. Thereby, the communication network system 100 of the fourth modification example can guarantee the communication opportunity by each communication device. That is, the communication network system 100 of the fourth modification example can suppress the execution of automatic driving by the vehicle from being hindered by switching the communication method to the second communication method.

[0257] In the communication network system 100 of the fourth modification example, when the situation of the vehicle grasped by the stop request device is during a fault diagnosis, the stop request signal is not transmitted. That is, in the communication network system 100 of the fourth modification example, when the vehicle is under fault diagnosis, the communication method is not switched to the second communication method. Thereby, the communication network system 100 of the fourth modification example can guarantee the communication opportunities for each communication device. That is, the communication network system 100 of the fourth modification example can suppress the situation where the execution of the fault diagnosis by the vehicle is hindered by switching the communication method to the second communication method.

[0258] · In the fourth modification example, the first communication device 10 as the stop request device acquires the communication error situation for all the communication devices in the communication network system 100. On the other hand, the first communication device 10 may acquire the communication error situation only for a specific communication device.

[0259] · In the fourth modification example, the first communication device 10 as the stop request device acquires the communication error situation for each communication device in the communication network system 100. On the other hand, the first communication device 10 may acquire the communication error situation for the entire communication network system 100.

[0260] In this case, as the communication error situation, the stop request device acquires information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system 100 of the fourth modification example.

[0261] In this case, in the communication network system 100 of the fourth modification example, as the communication error situation, the stop request device acquires information on the occurrence frequency of communication errors in the entire communication network system 100 of the fourth modification example. Thereby, the communication network system 100 of the fourth modification example can switch the communication method of the communication device to the second communication method according to the occurrence frequency of communication errors in the data transmitted in the communication network system 100 of the fourth modification example.

[0262] · In the fourth modification example, the first communication device 10, which is a stop request device, transmits an interference request signal based on the acquired error situation and the grasped vehicle situation. On the other hand, the first communication device 10 as a stop request device may transmit a stop request signal based only on the acquired error situation without grasping the vehicle situation. In this case, the management device 50 that has received the stop request signal stops transmitting the start signal 40 based on the vehicle situation after grasping the vehicle situation.

[0263] FIG. 22 shows a specific example of communication when the first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the fifth modification example switch the communication method to the second communication method. The first communication device 10, the second communication device 20, and the management device 50 in the communication network system 100 of the fifth modification example execute the communication shown in FIG. 22 instead of the communication mode shown in FIG. 8.

[0264] In the communication shown in FIG. 22, when the number of communication errors that occur while any communication device in the communication network system 100 transmits data a predetermined number of times reaches or exceeds a preset value, the first communication device 10 transmits a stop request signal to the management device 50.

[0265] Then, when the management device 50 that has received the stop request signal determines that the communication device can transition to the second communication method, it stops transmitting the start signal 40. As a result, the first communication device 10, the second communication device 20, and the management device 50 stop sensing the start signal 40.

[0266] As shown in the middle of FIG. 22, when the state where the first communication device 10, the second communication device 20, and the management device 50 do not sense the start signal for a predetermined time continues, they transition to the second communication method. In this way, the communication devices in the communication network system 100 of the fifth modification example switch the communication method to the second communication method.

[0267] The communication mode after the communication device switches to the second communication method is the same as that in FIG. 8. In the fifth modification example, similar to the third and fourth modification examples, the first communication device 10 does not need to be a jamming device. Therefore, in the fifth modification example, the first communication device 10 does not execute the series of processes shown in FIG. 10.

[0268] FIG. 23 shows a series of processes executed when the first communication device 10 transmits a stop request signal. This series of processes is executed by the processing device 11 of the first communication device 10. This series of processes is executed when the first communication device 10 obtains information on the number of communication errors that occurred while transmitting data a predetermined number of times for any one of the first communication device 10 itself, the second communication device 20, and the management device 50.

[0269] As shown in FIG. 23, when starting this series of processes, in the process of step S161, the processing device 11 determines whether the number of communication errors in the communication device for which the information was obtained is equal to or greater than a predetermined value. This process is the same as the process of step S101 in FIG. 10.

[0270] In the process of step S161, when the processing device 11 determines that the number of communication errors is not equal to or greater than the predetermined value (step S161: NO), this series of processes ends. In the process of step S161, when the processing device 11 determines that the number of communication errors is equal to or greater than the predetermined value (step S161: YES), the process proceeds to step S162. In the process of step S162, the processing device 21 transmits a stop request signal. At this time, the processing device 11 transmits the stop request signal according to the first communication method. This process corresponds to the process executed by the first communication device 10 in the upper part of FIG. 22.

[0271] FIG. 24 shows the flow of a series of processes when the management device 50 stops transmitting the start signal. This series of processes is executed by the processing device 51 of the management device 50. This series of processes is executed when the management device 50 receives a stop request signal.

[0272] As shown in FIG. 24, when starting this series of processes, in the process of step S171, the processing device 51 grasps the situation of the vehicle. This process is the same as the process executed by the processing device 11 in step S102 of FIG. 10.

[0273] In the process of the next step S172, the processing device 51 determines whether the communication device in the communication network system 100 of the fifth modification example can shift to the second communication method. This process is the same as the process executed by the processing device 11 in step S103 of FIG. 10.

[0274] In the process of step S172, when the processing device 51 determines that the communication device cannot shift to the second communication method (step S172: NO), this series of processes is terminated. In the process of step S172, when the processing device 51 determines that the communication device can shift to the second communication method (step S172: YES), the process proceeds to step S173. In the process of step S173, the processing device 51 stops transmitting the start signal 40. This process corresponds to the process executed by the management device 50 in the upper part of FIG. 22.

[0275] The communication network system 100 is mounted on the vehicle. The management device 50 grasps the situation of the vehicle. When the management device 50 receives the stop request signal, it stops transmitting the start signal based on the grasped situation of the vehicle.

[0276] In the communication network system 100 of the fifth modification example, the stop request device determines whether to stop transmitting the start signal 40 according to the situation of the vehicle. Thereby, the communication network system 100 of the fifth modification example can prioritize ensuring the data transmission opportunity by not stopping the transmission of the start signal 40 depending on the situation of the vehicle.

[0277] <Supplementary Note> Describe the technical idea that can be grasped from the above embodiments and modification examples. [Appendix 1] A communication network system composed of a plurality of communication devices, the communication network system comprising: a management device that transmits a start signal to the plurality of communication devices; and an interference device that transmits an interference signal for interfering with the detection of the start signal by the plurality of communication devices. The plurality of communication devices communicate with each other using a first communication method in which each communication device transmits data in a predetermined order after detecting the start signal. The interference device transmits the interference signal according to the communication error situation in the communication network system. When the state in which the plurality of communication devices do not detect the start signal continues for a predetermined time, the communication method is switched to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order. A communication network system.

[0278] [Appendix 2] The interference device according to [Appendix 1], wherein the interference device acquires the communication error situation in the communication network system and transmits the interference signal based on the acquired communication error situation.

[0279] [Appendix 3] The communication network system according to [Appendix 2], wherein the communication network system is mounted on a vehicle, and the interference device grasps the situation of the vehicle and transmits the interference signal based on the acquired communication error situation and the grasped situation of the vehicle.

[0280] [Appendix 4] The interference device according to [Appendix 2] or [Appendix 3], wherein the interference device acquires information on the number of communication errors that occurred while the communication device transmits data a predetermined number of times as the communication error situation.

[0281] [Appendix 5] The interference device according to [Appendix 2] or [Appendix 3], wherein the interference device acquires information on the number of communication errors that occurred while data is transmitted a predetermined number of times in the communication network system as the communication error situation.

[0282] [Appendix 6] The interference device transmits the interference signal when the number of communication errors acquired as the communication error situation is equal to or greater than a preset value. The communication network system according to [Appendix 4] or [Appendix 5].

[0283] [Appendix 7] A preset value is set for each communication device, and the interference device transmits the interference signal when the number of communication errors for any one of the communication devices becomes equal to or greater than the preset value. The communication network system according to [Appendix 4].

[0284] [Appendix 8] The communication network system includes an interference request device that transmits an interference request signal for requesting the interference device to transmit the interference signal. The interference request device acquires the communication error situation in the communication network system and transmits the interference request signal based on the acquired communication error situation. The interference device transmits the interference signal when it receives the interference request signal. The communication network system according to [Appendix 1].

[0285] [Appendix 9] The communication network system is mounted on a vehicle, and the interference request device grasps the situation of the vehicle and transmits the interference request signal based on the acquired communication error situation and the grasped situation of the vehicle. The communication network system according to [Appendix 8].

[0286] [Appendix 10] The communication network system is mounted on a vehicle, and the interference device grasps the situation of the vehicle and transmits the interference signal based on the grasped situation of the vehicle when it receives the interference request signal. The communication network system according to [Appendix 8].

[0287] [Appendix 11] The interference request device acquires, as the communication error situation, information on the number of communication errors that occurred while the communication device transmitted data a predetermined number of times. The communication network system according to any one of [Appendix 8] to [Appendix 10].

[0288] [Appendix 12] The interference request device acquires, as the communication error situation, information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system. The communication network system according to any one of [Appendix 8] to [Appendix 10].

[0289] [Appendix 13] The interference request device transmits the interference request signal when the number of communication errors acquired as the communication error situation is equal to or greater than a preset value. The communication network system according to [Appendix 11] or [Appendix 12].

[0290] [Appendix 14] A preset value is set for each communication device, and the interference request device transmits the interference request signal when the number of communication errors for any one of the communication devices is equal to or greater than the preset value. The communication network system according to [Appendix 11].

[0291] [Appendix 15] When the grasped situation of the vehicle is during autonomous driving, the interference device does not transmit the interference signal. The communication network system according to any one of [Appendix 3] to [Appendix 7] and [Appendix 10] to [Appendix 14].

[0292] [Appendix 16] When the grasped situation of the vehicle is during fault diagnosis, the interference device does not transmit the interference signal. The communication network system according to any one of [Appendix 3] to [Appendix 7] and [Appendix 10] to [Appendix 14].

[0293] [Appendix 17] When the grasped situation of the vehicle is during autonomous driving, the interference request device does not transmit the interference request signal. The communication network system according to any one of [Appendix 9] and [Appendix 11] to [Appendix 14].

[0294] [Appendix 18] When the grasped situation of the vehicle is during fault diagnosis, the interference request device does not transmit the interference request signal. The communication network system according to any one of [Appendix 9] and [Appendix 11] to [Appendix 14].

[0295] [Appendix 19] A jamming device applied to a communication network system including a plurality of communication devices and a management device that transmits a start signal to the communication devices. After sensing the start signal, the plurality of communication devices communicate with each other using a first communication method in which each communication device transmits data in a predetermined order. However, when the state of not sensing the start signal continues for a predetermined time, the communication method is set to switch to a second communication method in which data is transmitted when no other communication device is transmitting data, regardless of the predetermined order. A jamming device that transmits a jamming signal that interferes with the sensing of the start signal by the communication device according to the communication error situation in the communication network system.

[0296] [Appendix 20] The jamming device according to [Appendix 19], which acquires the communication error situation in the communication network system and transmits the jamming signal based on the acquired communication error situation.

[0297] [Appendix 21] The communication network system is mounted on a vehicle, grasps the situation of the vehicle, and transmits the jamming signal based on the acquired communication error situation and the grasped situation of the vehicle. The jamming device according to [Appendix 20].

[0298] [Appendix 22] The jamming device according to [Appendix 20] or [Appendix 21], which acquires information on the number of communication errors that occurred while the communication device transmitted data a predetermined number of times as the communication error situation.

[0299] [Appendix 23] The jamming device according to [Appendix 20] or [Appendix 21], which acquires information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system as the communication error situation.

[0300] [Appendix 24] The jamming device according to [Appendix 22] or [Appendix 23], which transmits the jamming signal when the number of communication errors acquired as the communication error situation is equal to or greater than a predetermined value. [Appendix 25] A jamming device as described in [Appendix 22], wherein a preset value is set for each communication device, and when the number of communication errors for any one of the communication devices reaches or exceeds the preset value, a jamming signal is transmitted.

[0301] [Appendix 26] A jamming device as described in any one of [Appendix 21] to [Appendix 25], wherein when the grasped vehicle situation is during autonomous driving, the jamming signal is not transmitted. [Appendix 27] A jamming device as described in any one of [Appendix 21] to [Appendix 25], wherein when the grasped vehicle situation is during fault diagnosis, the jamming signal is not transmitted.

[0302] [Appendix 28] A communication network system composed of a plurality of communication devices, the communication network system includes a management device that transmits a start signal to the plurality of communication devices, after the plurality of communication devices sense the start signal, they communicate with each other using a first communication method in which each communication device transmits data in a predetermined order, the management device stops transmitting the start signal according to the communication error situation in the communication network system, and when the state of not sensing the start signal continues for a predetermined time in the plurality of communication devices, the communication method is switched to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order.

[0303] [Appendix 29] The communication network system as described in [Appendix 28], wherein the management device acquires the communication error situation in the communication network system and stops transmitting the start signal based on the acquired communication error situation.

[0304] [Appendix 30] The communication network system as described in [Appendix 29], wherein the communication network system is mounted on a vehicle, the management device grasps the vehicle situation, and stops transmitting the start signal based on the acquired communication error situation and the grasped vehicle situation.

[0305] [Appendix 31] The management device acquires, as the communication error situation, information on the number of communication errors that occurred while the communication device transmitted data a predetermined number of times. The communication network system according to [Appendix 29] or [Appendix 30].

[0306] [Appendix 32] The management device acquires, as the communication error situation, information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system. The communication network system according to [Appendix 29] or [Appendix 30].

[0307] [Appendix 33] In the communication network system according to [Appendix 31] or [Appendix 32], when the number of communication errors acquired as the communication error situation by the management device is equal to or greater than a preset value, the management device stops transmitting the start signal.

[0308] [Appendix 34] A preset value is set for each communication device, and in the communication network system according to [Appendix 31], when the number of communication errors for any one of the communication devices becomes equal to or greater than the preset value, the management device stops transmitting the start signal.

[0309] [Appendix 35] The communication network system includes a stop request device that transmits a stop request signal requesting the management device to stop transmitting the start signal. The stop request device acquires the communication error situation in the communication network system and transmits the stop request signal based on the acquired communication error situation. When the management device receives the stop request signal, it stops transmitting the start signal. The communication network system according to [Appendix 28].

[0310] [Appendix 36] The communication network system is mounted on a vehicle, and the stop request device grasps the situation of the vehicle and transmits the stop request signal based on the acquired communication error situation and the grasped situation of the vehicle. The communication network system according to [Appendix 35].

[0311] [Appendix 37] The communication network system is mounted on a vehicle, and the management device grasps the situation of the vehicle and stops transmitting the start signal based on the grasped situation of the vehicle when receiving the stop request signal. The communication network system according to [Appendix 35].

[0312] [Appendix 38] The stop request device acquires information on the number of communication errors that occurred while the communication device transmits data a predetermined number of times as the communication error situation. The communication network system according to any one of [Appendix 35] to [Appendix 37].

[0313] [Appendix 39] The stop request device acquires information on the number of communication errors that occurred while data is transmitted a predetermined number of times in the communication network system as the communication error situation. The communication network system according to any one of [Appendix 35] to [Appendix 37].

[0314] [Appendix 40] The stop request device transmits the stop request signal when the number of communication errors acquired as the communication error situation is equal to or greater than a preset value. The communication network system according to [Appendix 38] or [Appendix 39].

[0315] [Appendix 41] A preset value is set for each communication device, and the stop request device transmits the stop request signal when the number of communication errors for any one of the communication devices becomes equal to or greater than the preset value. The communication network system according to [Appendix 38].

[0316] [Appendix 42] When the grasped situation of the vehicle is in the middle of autonomous driving, the management device does not stop transmitting the start signal. The communication network system according to any one of [Appendix 30] to [Appendix 34] and [Appendix 37] to

[41] .

[0317] [Appendix 43] When the situation of the vehicle grasped by the management device is during a fault diagnosis, the transmission of the start signal is not stopped. A communication network system according to any one of [Appendix 30] to [Appendix 34] and [Appendix 37] to

[41] .

[0318] [Appendix 44] When the situation of the vehicle grasped by the stop request device is during autonomous driving, the stop request signal is not transmitted. A communication network system according to any one of [Appendix 36] and [Appendix 38] to [Appendix 41].

[0319] [Appendix 45] When the situation of the vehicle grasped by the stop request device is during a fault diagnosis, the stop request signal is not transmitted. A communication network system according to any one of [Appendix 36] and [Appendix 38] to [Appendix 41].

[0320] [Appendix 46] A management device that transmits a start signal in a communication network system composed of a plurality of communication devices. After the plurality of communication devices sense the start signal, they communicate with each other using a first communication method in which each communication device transmits data in a predetermined order. However, when the state of not sensing the start signal continues for a predetermined time, the communication method is set to switch to a second communication method in which data is transmitted when other communication devices are not transmitting data regardless of the predetermined order. A management device that stops the transmission of the start signal according to the communication error situation in the communication network system.

[0321] [Appendix 47] The management device according to [Appendix 46], which acquires the communication error situation in the communication network system and stops the transmission of the start signal based on the acquired communication error situation.

[0322] [Appendix 48] The communication network system is mounted on a vehicle, and stops the transmission of the start signal based on the acquired communication error situation and the situation of the vehicle grasped. The management device according to [Appendix 47].

[0323] [Appendix 49] As the communication error situation, the management device according to [Appendix 47] or [Appendix 48] that acquires information on the number of communication errors that occurred while the communication device transmits data a predetermined number of times.

[0324] [Appendix 50] As the communication error situation, the management device according to [Appendix 47] or [Appendix 48] that acquires information on the number of communication errors that occurred while data is transmitted a predetermined number of times in the communication network system.

[0325] [Appendix 51] The management device according to [Appendix 49] or [Appendix 50] that stops transmitting the start signal when the number of communication errors acquired as the communication error situation is equal to or greater than a preset value.

[0326] [Appendix 52] A preset value is set for each communication device, and the management device according to [Appendix 49] that stops transmitting the start signal when the number of communication errors for any one of the communication devices becomes equal to or greater than the preset value.

[0327] [Appendix 53] The management device according to any one of [Appendix 48] to [Appendix 52] that does not stop transmitting the start signal when the grasped vehicle situation is during autonomous driving. [Appendix 54] The management device according to any one of [Appendix 48] to [Appendix 52] that does not stop transmitting the start signal when the grasped vehicle situation is during fault diagnosis.

[0328] [Appendix 55] When the communication device has data to transmit immediately after switching the communication method from the first communication method to the second communication method, the communication network system according to any one of [Appendix 1] to [Appendix 18] and [Appendix 28] to [Appendix 45] sets an offset time from the moment of switching the communication method to the second communication method until the transmission of the data starts, and starts the transmission of the data when the set offset time has elapsed.

[0329] [Appendix 56] When the communication device switches the communication method from the first communication method to the second communication method, if there is data to be transmitted immediately after the switch to the second communication method, the offset time from the moment the communication method is switched to the second communication method until the transmission of the data starts is set to be shorter as the capacity of the data to be transmitted is larger, and the transmission of the data starts when the set offset time has elapsed. A communication network system according to any one of [Appendix 1] to [Appendix 18] and [Appendix 28] to [Appendix 45].

[0330] [Appendix 57] Each of the communication devices has a priority set in advance. When the communication device switches the communication method from the first communication method to the second communication method, if there is data to be transmitted immediately after the switch to the second communication method, the offset time from the moment the communication method is switched to the second communication method until the transmission of the data starts is set to be shorter as the priority is higher, and the transmission of the data starts when the set offset time has elapsed. A communication network system according to any one of [Appendix 1] to [Appendix 18] and [Appendix 28] to [Appendix 45].

Explanation of Reference Numerals

[0331] 10…First communication device 11…Processing device 12…Storage device 20…Second communication device 21…Processing device 22…Storage device 30…Communication bus 40…Start signal 41…First data 42…Second data 43…Third data 50…Management device 51…Processing device 52…Storage device 100…Communication network system

Claims

1. A communication network system composed of a plurality of communication devices, The communication network system, A management device that transmits a start signal to the plurality of communication devices, And a jamming device that transmits a jamming signal to interfere with the detection of the start signal by the plurality of communication devices. The plurality of communication devices, After detecting the start signal, communicate with each other using a first communication method in which each communication device transmits data in a predetermined order, The jamming device, Transmits the jamming signal according to the communication error situation in the communication network system, The plurality of communication devices, When the state of not detecting the start signal continues for a predetermined time, Switch the communication method to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order. A communication network system.

2. The jamming device, Obtains the communication error situation in the communication network system, Transmits the jamming signal based on the obtained communication error situation. The communication network system according to claim 1.

3. The communication network system is mounted on a vehicle, The jamming device, Grasps the situation of the vehicle, Transmits the jamming signal based on the obtained communication error situation and the grasped vehicle situation. The communication network system according to claim 2.

4. The jamming device, As the communication error situation, Obtain information on the number of times of the communication error that occurred while the communication device transmits data a predetermined number of times. The communication network system according to claim 2.

5. The interference device As the situation of the communication error In the communication network system, obtain information on the number of times of the communication error that occurred while data is transmitted a predetermined number of times. The communication network system according to claim 2.

6. The interference device When the number of times of the communication error obtained as the situation of the communication error is equal to or more than a predetermined value, transmit the interference signal. The communication network system according to claim 4 or claim 5.

7. The predetermined value is set for each communication device, The interference device When the number of times of the communication error for any of the communication devices becomes equal to or more than the predetermined value, transmit the interference signal. The communication network system according to claim 4.

8. The communication network system Includes an interference request device that transmits an interference request signal for requesting the interference device to transmit the interference signal, The interference request device Obtain the situation of the communication error in the communication network system, Based on the obtained situation of the communication error, transmit the interference request signal, The interference device When receiving the interference request signal, transmit the interference signal. The communication network system according to claim 1.

9. The communication network system is mounted on a vehicle, The interference request device Grasp the situation of the vehicle, and transmit the interference request signal based on the obtained situation of the communication error and the grasped situation of the vehicle. The communication network system according to claim 8.

10. The communication network system is mounted on a vehicle, The interference device, grasps the situation of the vehicle, when receiving the interference request signal, transmits the interference signal based on the grasped situation of the vehicle. The communication network system according to claim 8.

11. The interference request device, as the situation of the communication error, acquires information on the number of communication errors that occurred while the communication device transmitted data a predetermined number of times. The communication network system according to claim 8.

12. The interference request device, as the situation of the communication error, acquires information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system. The communication network system according to claim 8.

13. The interference request device, transmits the interference request signal when the number of communication errors acquired as the situation of the communication error is equal to or greater than a predetermined value. The communication network system according to claim 11 or claim 12.

14. The predetermined value is set for each communication device, The interference request device, transmits the interference request signal when the number of communication errors for any of the communication devices becomes equal to or greater than the predetermined value. The communication network system according to claim 11.

15. The jamming device When the situation of the vehicle grasped is during autonomous driving, does not transmit the jamming signal The communication network system according to claim 3 or claim 10.

16. The jamming device When the situation of the vehicle grasped is during fault diagnosis, does not transmit the jamming signal The communication network system according to claim 3 or claim 10.

17. The jamming request device When the situation of the vehicle grasped is during autonomous driving, does not transmit the jamming request signal The communication network system according to claim 9.

18. The jamming request device When the situation of the vehicle grasped is during fault diagnosis, does not transmit the jamming request signal The communication network system according to claim 9.

19. A jamming device applied to a communication network system including a plurality of communication devices and a management device that transmits a start signal to the communication devices, The plurality of communication devices After sensing the start signal, communicate with each other using a first communication method in which each communication device transmits data in a predetermined order, When the state of not sensing the start signal continues for a predetermined time, It is set to switch the communication method to a second communication method in which data is transmitted when other communication devices are not transmitting data regardless of the predetermined order, According to the communication error situation in the communication network system, Transmits a jamming signal that interferes with the sensing of the start signal by the communication device Jamming device.

20. A communication network system composed of a plurality of communication devices, The communication network system, Includes a management device that transmits a start signal to the plurality of communication devices, The plurality of communication devices, After detecting the start signal, they communicate with each other using a first communication method in which each communication device transmits data in a predetermined order, The management device, Stops transmitting the start signal according to the communication error situation in the communication network system, The plurality of communication devices, When the state of not detecting the start signal continues for a predetermined time, Regardless of the predetermined order, when no other communication device is transmitting data, switch the communication method to a second communication method for transmitting data Communication network system.

21. The management device, Obtains the communication error situation in the communication network system, Stops transmitting the start signal based on the obtained communication error situation The communication network system according to claim 20.

22. The communication network system is mounted on a vehicle, The management device, Grasps the situation of the vehicle, Stops transmitting the start signal based on the obtained communication error situation and the grasped vehicle situation The communication network system according to claim 21.

23. The management device, As the communication error situation, Obtains information on the number of communication errors that occurred while the communication device transmitted data a predetermined number of times The communication network system according to claim 21.

24. The management device As the status of the communication error, Obtain information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system The communication network system according to claim 21.

25. The management device When the number of communication errors obtained as the status of the communication error is equal to or greater than a preset value, stop transmitting the start signal The communication network system according to claim 23 or claim 24.

26. A preset value is set for each communication device, The management device When the number of communication errors for any of the communication devices becomes equal to or greater than the preset value, stop transmitting the start signal The communication network system according to claim 23.

27. The communication network system Includes a stop request device that transmits a stop request signal requesting the management device to stop transmitting the start signal, The stop request device Obtain the status of the communication error in the communication network system, Based on the obtained status of the communication error, transmit the stop request signal, The management device When the stop request signal is received, stop transmitting the start signal The communication network system according to claim 20.

28. The communication network system is mounted on a vehicle, The stop request device Grasp the status of the vehicle, Transmit the stop request signal based on the obtained communication error situation and the grasped vehicle situation. The communication network system according to claim 27.

29. The communication network system is mounted on a vehicle, The management device, Grasps the situation of the vehicle, When receiving the stop request signal, Stops transmitting the start signal based on the grasped vehicle situation. The communication network system according to claim 27.

30. The stop request device, As the communication error situation, Obtains information on the number of communication errors that occurred while the communication device transmitted data a predetermined number of times. The communication network system according to claim 27.

31. The stop request device, As the communication error situation, Obtains information on the number of communication errors that occurred while data was transmitted a predetermined number of times in the communication network system. The communication network system according to claim 27.

32. The stop request device, Transmits the stop request signal when the number of communication errors obtained as the communication error situation is equal to or greater than a preset value. The communication network system according to claim 30 or claim 31.

33. The preset value is set for each communication device, The stop request device, Transmits the stop request signal when the number of communication errors for any of the communication devices becomes equal to or greater than the preset value. The communication network system according to claim 30.

34. The management device When the grasped situation of the vehicle is during autonomous driving, does not stop transmitting the start signal The communication network system according to claim 22 or claim 29.

35. The management device When the grasped situation of the vehicle is during fault diagnosis, does not stop transmitting the start signal The communication network system according to claim 22 or claim 29.

36. The stop request device When the grasped situation of the vehicle is during autonomous driving, does not transmit the stop request signal The communication network system according to claim 28.

37. The stop request device When the grasped situation of the vehicle is during fault diagnosis, does not transmit the stop request signal The communication network system according to claim 28.

38. A management device that transmits a start signal in a communication network system composed of a plurality of communication devices, The plurality of communication devices After sensing the start signal, communicate with each other using a first communication method in which each communication device transmits data in a predetermined order, When the state of not sensing the start signal continues for a predetermined time, It is set to switch the communication method to a second communication method in which data is transmitted when no other communication device is transmitting data regardless of the predetermined order, According to the communication error situation in the communication network system, Stop transmitting the start signal Management device.

39. The communication device When switching the communication method from the first communication method to the second communication method, if there is data to be transmitted immediately after switching to the second communication method, set an offset time from the moment when the communication method is switched to the second communication method until the transmission of the data starts, and start the transmission of the data when the set offset time has elapsed The communication network system according to claim 1 or claim 20.

40. The communication device, When switching the communication method from the first communication method to the second communication method, if there is data to be transmitted immediately after switching to the second communication method, set the offset time from the moment when the communication method is switched to the second communication method until the transmission of the data starts so that the larger the capacity of the data to be transmitted, the shorter the time, and start the transmission of the data when the set offset time has elapsed The communication network system according to claim 1 or claim 20.

41. Each of the communication devices, has a priority set in advance, The communication device, When switching the communication method from the first communication method to the second communication method, if there is data to be transmitted immediately after switching to the second communication method, set the offset time from the moment when the communication method is switched to the second communication method until the transmission of the data starts so that the higher the priority, the shorter the time, and start the transmission of the data when the set offset time has elapsed The communication network system according to claim 1 or claim 20.

42. A vehicle comprising the communication network system according to claim 1.

43. A vehicle comprising the communication network system according to claim 20.

44. A program applied to a jamming device of a communication network system, wherein the communication network system comprises a plurality of communication devices and a management device that transmits a start signal, wherein the plurality of communication devices communicate with each other using a first communication method in which, after detecting the start signal, they transmit their respective data in a predetermined order, but when the state of not detecting the start signal continues for a predetermined time, it is set to switch the communication method to a second communication method in which data is transmitted when no other communication device is transmitting data, regardless of the predetermined order, and based on the communication error situation in the communication network system, the jamming device is made to transmit a jamming signal that interferes with the detection of the start signal by the communication device program.

45. A program applied to a management device that transmits a start signal in a communication network system constituted by a plurality of communication devices, wherein the plurality of communication devices communicate with each other using a first communication method in which, after detecting the start signal, they transmit their respective data in a predetermined order, but when the state of not detecting the start signal continues for a predetermined time, it is set to switch the communication method to a second communication method in which data is transmitted when no other communication device is transmitting data, regardless of the predetermined order, and based on the communication error situation in the communication network system, the management device is made to stop transmitting the start signal program.

46. It is composed of a plurality of communication devices, a management device that transmits a start signal, and a jamming device that transmits a jamming signal for interfering with the detection of the start signal by the communication device, wherein the plurality of communication devices communicate with each other using a first communication method in which, after detecting the start signal, they transmit their respective data in a predetermined order, and the step of the jamming device transmitting the jamming signal based on the communication error situation in the communication network system, and the step of the plurality of communication devices switching the communication method to a second communication method in which, when the state of not detecting the start signal continues for a predetermined time, they transmit data when no other communication device is transmitting data regardless of the predetermined order, are included communication method.

47. It is composed of a plurality of communication devices, and includes a management device that transmits a start signal, wherein the plurality of communication devices communicate with each other using a first communication method in which, after detecting the start signal, they transmit their respective data in a predetermined order, and the step of the management device stopping the transmission of the start signal based on the communication error situation in the communication network system, and the step of the plurality of communication devices switching the communication method to a second communication method in which, when the state of not detecting the start signal continues for a predetermined time, they transmit data when no other communication device is transmitting data regardless of the predetermined order, are included communication method.

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