Communication device and communication method

Abstract

To provide a communication device, a communication system, and a communication method that can reduce a communication load in wired communication.SOLUTION: A communication device according to an aspect of an embodiment is configured to be able to communicate with a receiving device and includes a communication control unit. The communication control unit transmits predetermined data to the receiving device by wireless communication and receives or transmits an acknowledgement signal related to confirmation of transmission and reception of the predetermined data by wired communication.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a communication device Place and communication methods. [Background technology]

[0002] BACKGROUND ART Various devices have been proposed in the past that are connected to an ECU (Electronic Control Unit) mounted on a vehicle via a communication bus or the like to perform wired communication (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-048439 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in recent years, for example, there has been a trend toward an increase in the amount of data traffic on communication buses, which has led to a risk of an excessive increase in the communication load in wired communication. The above-mentioned conventional technology has room for further improvement in terms of reducing the communication load in wired communication.

[0005] The present invention has been made in view of the above, and provides a communication device capable of reducing the communication load in wired communication. Place The purpose of this document is to provide a method of communication. [Means for solving the problem]

[0006] In order to solve the above problems and achieve the object, the present invention provides a communication device capable of communicating with a receiving device, the communication device including a communication control unit, which transmits predetermined data to the receiving device via wireless communication and receives or transmits a confirmation signal for confirming transmission and reception of the predetermined data via wired communication. [Effects of the Invention]

[0007] According to the present invention, it is possible to reduce the communication load in wired communication. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an overview of a communication method according to the first embodiment. [Figure 2] FIG. 2 is a block diagram showing an example of the configuration of a communication system including a communication device according to the first embodiment. [Figure 3] FIG. 3 is a block diagram showing an example of the configuration of the central gateway ECU. [Figure 4] FIG. 4 is a block diagram showing an example of the configuration of an in-vehicle ECU. [Figure 5] FIG. 5 is a flowchart showing a processing procedure executed by the central gateway ECU. [Figure 6] FIG. 6 is a block diagram showing an example of the configuration of a transmission-side ECU according to the second embodiment. [Figure 7] FIG. 7 is a diagram illustrating the transmission of predetermined data and an authentication signal. [Figure 8] FIG. 8 is a block diagram showing an example of the configuration of a receiving-side ECU according to the second embodiment. [Figure 9] FIG. 9 is a diagram illustrating an example of a processing sequence executed by the communication system according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of a communication device, a communication system, and a communication method disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiments described below.

[0010] (First embodiment) <Communication Method Overview> First, an outline of a communication method by a communication device according to the first embodiment will be described below with reference to Fig. 1. Fig. 1 is a diagram showing an outline of a communication method according to the first embodiment.

[0011] The communication method according to the first embodiment is executed, for example, by a communication device 10 included in a communication system 1. Note that the communication system 1 is mounted on a vehicle (not shown), but is not limited to this, and may be mounted on, for example, other types of devices that perform communication processing.

[0012] 1, the communication system 1 includes a communication device 10 and an in-vehicle ECU 50. The in-vehicle ECU 50 is an example of a receiving device, and is a device that receives various data and the like from the communication device 10, as will be described later. Note that the receiving device has at least a (wireless) receiving function, but also includes devices that have other functions (for example, a wireless or wired transmission function, a data processing function, a control function, etc.).

[0013] A vehicle is equipped with a plurality of on-board ECUs 50. While Fig. 1 illustrates an example in which there are two on-board ECUs 50 for the sake of simplicity, the number of on-board ECUs is not limited to this, and there may be three or more, or just one. The on-board ECU 50 may perform, for example, processing related to vehicle control, but is not limited to this.

[0014] The communication device 10 and the multiple on-board ECUs 50 are connected by an on-board network. Specifically, the communication device 10 and the multiple on-board ECUs 50 are connected via a communication bus (communication line) B such as a CAN (Controller Area Network) bus, and are configured to be able to communicate with each other via wires.

[0015] In recent years, the amount of data communication has tended to increase in wired communication using the communication bus B, which may result in an excessive increase in communication load. That is, a vehicle is configured to be able to communicate with, for example, an external server device 210 (see FIG. 2, which will be described later), and is able to acquire various information, such as map information and traffic information, distributed from the server device 210. Some or all of the various information may be transmitted to the in-vehicle ECU 50 via the communication bus B, which may result in an excessive increase in communication load of wired communication using the communication bus B.

[0016] Therefore, the communication device 10 according to this embodiment is configured to be able to reduce the communication load in wired communication.

[0017] More specifically, the communication device 10 is configured to be capable of wireless communication with the in-vehicle ECU 50. That is, the communication device 10 is configured to be capable of communicating with the in-vehicle ECU 50 by both wired communication and wireless communication. Note that, for example, Wi-Fi (registered trademark) or Bluetooth (registered trademark) can be used as a communication method for wireless communication, but the present invention is not limited to these, and other types of communication methods may also be used.

[0018] The communication device 10 according to this embodiment first acquires predetermined data to be transmitted to the vehicle-mounted ECU 50 (step S1). The predetermined data is, for example, data that is to be transmitted simultaneously to a plurality of vehicle-mounted ECUs 50. As an example, the predetermined data includes some or all of data indicating the rotation speed of a drive source such as a vehicle engine or electric motor, vehicle speed, vehicle state (e.g., brake or steering state), coolant temperature, etc.

[0019] In the above description, the predetermined data is data that is simultaneously transmitted to a plurality of in-vehicle ECUs 50, but this is not limited thereto and may be, for example, data that is transmitted at individual times to the in-vehicle ECUs 50. In addition, in the above description, the content of the predetermined data is specifically shown, but this is merely an example and is not limiting, and the predetermined data can be set to any data.

[0020] Next, the communication device 10 transmits predetermined data to the in-vehicle ECUs 50 via wireless communication (step S2). Specifically, the communication device 10 transmits the predetermined data to the plurality of in-vehicle ECUs 50 simultaneously via wireless communication.

[0021] When the in-vehicle ECU 50 receives the predetermined data transmitted from the communication device 10, it generates a confirmation signal for confirming transmission and reception (more specifically, reception) of the predetermined data (step S3). More specifically, when the multiple in-vehicle ECUs 50 receive the predetermined data, they each generate a confirmation signal. Here, the confirmation signal is a response signal (e.g., ACK (acknowledgement)) for confirming on the communication device 10 side that the predetermined data has been normally received by the in-vehicle ECU 50.

[0022] Then, the communication device 10 receives the confirmation signal generated by the in-vehicle ECU 50 via wired communication (step S4). That is, the in-vehicle ECU 50 transmits the generated confirmation signal to the communication device 10 via wired communication (specifically, via the communication bus B) at a predetermined timing, and the communication device 10 receives the confirmation signal. By receiving the confirmation signal, the communication device 10 confirms that the in-vehicle ECU 50 has normally received the predetermined data.

[0023] In this way, the communication device 10 according to this embodiment transmits predetermined data to the in-vehicle ECU 50 by wireless communication, and receives the confirmation signal transmitted from the in-vehicle ECU 50 by wired communication.

[0024] As a result, in this embodiment, the communication load in wired communication can be reduced. That is, by transmitting predetermined data wirelessly, the communication load in wired communication can be reduced by the amount of data communication of the predetermined data, compared to when the predetermined data is transmitted via wired communication.

[0025] Furthermore, in this embodiment, the predetermined data is data that has a relatively large communication load, such as data that is transmitted simultaneously to multiple vehicle ECUs 50, and the transmission of such predetermined data is performed wirelessly, thereby making it possible to further reduce the communication load in wired communication.

[0026] <Communication system including communication device> Next, the configuration of a communication system 1 including the communication device 10 according to the first embodiment will be described with reference to Fig. 2. Fig. 2 is a block diagram showing an example of the configuration of the communication system 1 including the communication device 10 according to the first embodiment.

[0027] As shown in FIG. 2, the communication system 1 includes the above-described communication device 10, an in-vehicle ECU 50, a sensor 100, a connected gateway ECU 200, and a server device 210.

[0028] In this embodiment, the communication device 10 is realized by a central gateway ECU. That is, the central gateway ECU is an example of the communication device 10. In the following, the central gateway ECU functioning as the communication device 10 may be referred to as a CGW (Central Gateway) ECU 10. The detailed configuration of the CGW ECU 10 will be described later with reference to FIG. 3.

[0029] A connected gateway ECU 200 is communicably connected to the CGWECU 10. The connected gateway ECU 200 and the server device 210 are communicably connected via a communication network N such as the Internet.

[0030] As described above, the server device 210 is a server device that can distribute various types of information such as map information, traffic information, and weather information.

[0031] The connected gateway ECU 200 includes an in-vehicle communication module such as a DCM (Data Communication Module), and communicates with the server device 210. For example, the connected gateway ECU 200 can acquire various types of information distributed from the server device 210 and transmit the acquired information to the in-vehicle ECU 50, etc. via the CGWECU 10 and the communication bus B.

[0032] Furthermore, the CGWECU 10 is communicatively connected to the in-vehicle ECUs 50 via a communication bus B. More specifically, the CGWECU 10 is connected to a plurality of communication buses B. Each of the plurality of communication buses B is connected to a plurality of in-vehicle ECUs 50. That is, the CGWECU 10 can relay data transmission and reception between the in-vehicle ECUs 50.

[0033] 2, among the multiple communication buses B, communication bus Ba is a powertrain system bus to which powertrain system on-board ECUs 50a1, 50a2, and 50a3 are connected, and communication bus Bb is a chassis system bus to which chassis system on-board ECUs 50b1, 50b2, and 50b3 are connected.

[0034] In the following description, when the communication buses Ba and Bb are described without any particular distinction, they will be referred to as "communication bus B," and when the in-vehicle ECUs 50a1-a3 and 50b1-b3 are described without any particular distinction, they will be referred to as "in-vehicle ECU 50."

[0035] 2 shows an example in which the types of communication bus B and on-board ECU 50 are those of a powertrain system and a chassis system, but this is not limiting and other types of communication bus B and on-board ECU 50, such as those of a body system, may be included. The number of communication buses B and on-board ECU 50 shown in FIG. 2 is merely an example and is not limited thereto, and can be set to any number. The detailed configuration of the on-board ECU 50 will be described later with reference to FIG. 4.

[0036] The sensor 100 is various sensors necessary for vehicle control, for example. There are a plurality of sensors 100. For example, among the plurality of sensors 100, the sensor 100a is a rotational speed sensor and outputs a signal indicating the rotational speed of the drive source to the in-vehicle ECU 50 (in the example of FIG. 2, the in-vehicle ECU 50a1). The in-vehicle ECU 50a1 can output the signal output from the sensor 100a to, for example, the CGW ECU 10 or the like.

[0037] Also, for example, the sensor 100b is a brake sensor and outputs a signal indicating the state of the brake, such as the amount of depression of a brake pedal (not shown), to the in-vehicle ECU 50 (in the example of FIG. 2, the in-vehicle ECU 50b1). The in-vehicle ECU 50b1 can output the signal output from the sensor 100b to, for example, the CGW ECU 10 or the like.

[0038] In the following, when the sensors 100a and 10 b are not particularly distinguished and described, they are referred to as "sensor 100". Also, in FIG. 2, an example where the sensor 100 is a rotational speed sensor or a brake sensor is shown, but it is not limited thereto. For example, other types of sensors 100 such as a vehicle speed sensor, a steering angle sensor, and a coolant water temperature sensor may be included. Also, the number of sensors 100 shown in FIG. 2 is merely an example and is not limited, and can be set to any number.

[0039] <Configuration of the CGW ECU (Central Gateway ECU)> Next, the configuration of the CGW ECU 10 will be specifically described with reference to FIG. 3. FIG. 3 is a block diagram showing a configuration example of the CGW ECU 10. In the block diagrams such as FIG. 3, only the components necessary for explaining the features of the present embodiment are represented by functional blocks, and the description of general components is omitted.

[0040] In other words, each component shown in a block diagram such as Figure 3 is a functional concept, and does not necessarily have to be physically configured as shown. For example, the specific form of distribution and integration of each functional block is not limited to that shown, and all or part of it can be functionally or physically distributed and integrated in any unit depending on various loads, usage conditions, etc.

[0041] As shown in FIG. 3, the CGWECU 10 includes a wireless communication unit 11, a wired communication unit 12, a control unit 20, and a storage unit 30.

[0042] The wireless communication unit 11 is a communication interface that is connected to the in-vehicle ECU 50 via wireless communication so as to be able to communicate bidirectionally, and transmits and receives various data including predetermined data to and from the in-vehicle ECU 50, for example.

[0043] The wired communication unit 12 is a communication interface that is connected to the in-vehicle ECU 50 via wired communication using a communication bus B (see Figure 2) or the like to enable bidirectional communication, and transmits and receives various data including confirmation signals between the in-vehicle ECU 50 and the in-vehicle ECU 50, for example.

[0044] The control unit 20 includes an acquisition unit 21 and a communication control unit 22, and includes, for example, a computer having a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), a hard disk drive, input / output ports, etc., and various circuits.

[0045] The CPU of the computer functions as the acquisition unit 21 and the communication control unit 22 of the control unit 20 by, for example, reading and executing a program stored in the ROM.

[0046] Furthermore, at least a part or all of the acquisition unit 21 and communication control unit 22 of the control unit 20 can be configured with hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0047] The storage unit 30 is configured with a storage device such as a nonvolatile memory, a data flash, a hard disk drive, etc. The storage unit 30 stores predetermined data 31, various programs, and the like.

[0048] As described above, the predetermined data 31 is data to be transmitted to the in-vehicle ECU 50. For example, the predetermined data 31 includes data to be transmitted simultaneously to a plurality of in-vehicle ECUs 50 (such as the rotation speed of the drive source), but is not limited to this.

[0049] The acquisition unit 21 of the control unit 20 acquires predetermined data. The acquisition unit 21 stores the acquired data as predetermined data 31 in the storage unit 30. For example, when acquiring the rotation speed of the drive source as the predetermined data, the acquisition unit 21 acquires a signal indicating the rotation speed of the drive source from the sensor 100a via the in-vehicle ECU 50a1 (see FIG. 2 for both). At this time, the acquisition unit 21 acquires the signal indicating the rotation speed of the drive source by wired communication, but this is not limitative and the signal may be acquired by wireless communication. Then, the acquisition unit 21 stores the acquired rotation speed of the drive source as predetermined data 31 in the storage unit 30.

[0050] The communication control unit 22 wirelessly transmits predetermined data to the in-vehicle ECU 50. For example, the communication control unit 22 reads the predetermined data 31 from the storage unit 30 and transmits the read data to the in-vehicle ECU 50 via the wireless communication unit 11 wirelessly.

[0051] In this way, by transmitting the specified data wirelessly, the communication load in wired communication can be reduced by the amount of data communication of the specified data, compared to when the specified data is transmitted via wired communication, for example.

[0052] Furthermore, the communication control unit 22 wirelessly transmits predetermined data to the plurality of in-vehicle ECUs 50 (in-vehicle ECUs 50a1 to a3, 50b1 to b3) all at once. In other words, the communication control unit 22 broadcasts the predetermined data to the plurality of in-vehicle ECUs 50 via wireless communication.

[0053] In this way, data that has a relatively large communication load, such as data that is transmitted simultaneously to multiple vehicle ECUs 50, is set as the specified data, and the transmission of such specified data is performed via wireless communication, thereby making it possible to further reduce the communication load in wired communication.

[0054] As described above, when the in-vehicle ECU 50 receives the predetermined data, it generates a confirmation signal for confirming transmission and reception (more specifically, reception) of the predetermined data, and transmits the generated confirmation signal via wired communication to the CGWECU 10. The confirmation signal is a response signal (ACK) for the CGWECU 10 to confirm that the in-vehicle ECU 50 has normally received the predetermined data.

[0055] Therefore, the communication control unit 22 receives, via wired communication, the confirmation signal generated by the in-vehicle ECU 50. In other words, the communication control unit 22 receives, as a confirmation signal, a response signal (ACK) for confirming that the in-vehicle ECU 50 has received the predetermined data, from the in-vehicle ECU 50 via the wired communication unit 12. Then, by receiving the response signal (confirmation signal), the communication control unit 22 can confirm that the in-vehicle ECU 50 has normally received the predetermined data.

[0056] However, there may be some problem that prevents the transmission or reception of the predetermined data from being performed normally. In this embodiment, even if such a problem occurs, it is possible to deal with the problem appropriately.

[0057] Specifically, when the state of reception of the response signal (confirmation signal) satisfies a predetermined condition, the communication control unit 22 may retransmit the predetermined data by wireless communication to the in-vehicle ECU 50. As a result, even if the previous transmission or reception of the predetermined data was not performed normally, retransmission of the predetermined data may result in the transmission and reception of the predetermined data being performed normally, and therefore it becomes possible to appropriately respond to the above-mentioned event.

[0058] More specifically, the communication control unit 22 transmits predetermined data to a plurality of in-vehicle ECUs 50, and then performs processing to wait for a response signal to be returned from each of the in-vehicle ECUs 50. For example, after transmitting the predetermined data, the communication control unit 22 accepts the response signal for a predetermined period of time.

[0059] The specified period is set, for example, to the period from when the CGWECU10 and the on-board ECUs 50 are both normal and when the specified data is transmitted until it is assumed that response signals are returned from all on-board ECUs 50 to which the specified data was transmitted, but is not limited to this and can be set to any period.

[0060] After receiving the response signals for a predetermined period of time, the communication control unit 22 calculates a response signal response rate. For example, the communication control unit 22 calculates the proportion of in-vehicle ECUs 50 that have returned response signals to all in-vehicle ECUs 50 to which predetermined data has been transmitted, i.e., the response signal response rate.

[0061] The communication control unit 22 compares the calculated response rate of the response signal with a predetermined value. If the response rate is equal to or less than the predetermined value and there is sufficient time to transmit, the communication control unit 22 retransmits the predetermined data via wireless communication to the in-vehicle ECU 50. In other words, the condition that the response rate is equal to or less than the predetermined value and there is sufficient time to transmit is an example of the predetermined condition.

[0062] The predetermined value is set to a value that indicates, for example, that a problem has occurred during wireless transmission of the predetermined data if the response rate is equal to or less than this value. Specifically, the predetermined value is set to a value that indicates that the predetermined data has not reached some or all of the multiple on-board ECUs 50 due to, for example, the influence of temporary harmful radio waves. The predetermined value is not limited to the above, and can be set to any value that is less than 100%, for example.

[0063] In addition, the transmission margin time is the time that indicates that there is a margin for retransmitting already transmitted specified data via wireless communication before the next timing for transmitting new specified data (more specifically, new specified data that is different from the already transmitted specified data).

[0064] Therefore, if the response rate is below a predetermined value and there is sufficient time for transmission, the communication control unit 22 will resend the specified data via wireless communication.For example, even if some problem occurred the last time the specified data was sent and the specified data was not sent or received normally, resending the data may result in the specified data being sent and received normally, thereby making it possible to respond appropriately to the above-mentioned events.

[0065] It should be noted that if the response rate is 100%, that is, if response signals have been returned from all of the in-vehicle ECUs 50 to which the predetermined data was transmitted, the communication control unit 22 will not perform the above-described processing such as retransmitting the predetermined data.

[0066] In addition, if a response signal is not received (replied), the communication control unit 22 may transmit specified data via wired communication to the in-vehicle ECU 50 that is not receiving (replying) a response signal, i.e., may switch from wireless communication to wired communication and transmit the specified data.

[0067] As a result, even if the specified data cannot be sent or received normally via wireless communication, it is possible that the specified data can be sent and received normally by sending it via wired communication, thereby making it possible to respond appropriately to the above-mentioned events.

[0068] To be more specific, for example, if the specified data reaches a certain number of the multiple vehicle ECUs 50 but does not reach some of the vehicle ECUs 50, the communication control unit 22 assumes that there is some problem on the receiving side of the wireless communication of the specified data, rather than a problem on the sending side of the wireless communication of the specified data, and transmits the specified data via wired communication to the vehicle ECUs 50 that do not receive (reply) a response signal.

[0069] More specifically, if the reply rate is greater than a predetermined value and less than 100%, the communication control unit 22 assumes that a problem has occurred on the receiving side of the wireless communication of the specified data, and transmits the specified data via wired communication to the vehicle ECU 50 that does not receive (reply from) a response signal.

[0070] Furthermore, when a response signal is not received (reply) and there is no transmission margin time, the communication control unit 22 may transmit predetermined data by wired communication to the in-vehicle ECU 50 that has not received the response signal. In other words, when, for example, the response rate is less than 100% and there is no margin to retransmit the predetermined data by wireless communication, the communication control unit 22 may transmit predetermined data by wired communication to the in-vehicle ECU 50 that has not received the response signal.

[0071] In this way, even if the communication control unit 22 does not receive a response signal and the specified data is not sent or received normally via wireless communication, the specified data may be sent and received normally by sending it via wired communication, thereby making it possible to respond appropriately to the above-mentioned events.

[0072] Furthermore, in this embodiment, the predetermined data is transmitted by wired communication only to the in-vehicle ECU 50 that does not receive (return) a response signal, so that an increase in the communication load in wired communication can be suppressed as much as possible.

[0073] Note that even if the above-described predetermined data is transmitted via wired communication, if the transmission or reception of the predetermined data is not performed normally, the communication control unit 22 may perform an abnormality handling process. For example, the communication control unit 22 may perform an abnormality handling process if the transmission of the predetermined data via wired communication satisfies an abnormality handling process condition.

[0074] The abnormality response processing conditions described above are, for example, when the specified data is not normally transmitted or received even after being transmitted via wired communication once or multiple times, but are not limited to this and can be set to any conditions.

[0075] Furthermore, abnormality response processing includes, for example, temporarily stopping the transmission of specified data to the vehicle ECU 50 that does not receive a response signal, or outputting diagnostics, but these are merely examples and are not limited to these, and can be set to any processing content.

[0076] <Automotive ECU configuration> Next, the configuration of the in-vehicle ECU 50 will be specifically described with reference to Fig. 4. Fig. 4 is a block diagram showing an example configuration of the in-vehicle ECU 50. As shown in Fig. 4, the in-vehicle ECU 50 includes a wireless communication unit 51, a wired communication unit 52, a control unit 60, and a storage unit 70.

[0077] The wireless communication unit 51 is a communication interface that is connected to the CGWECU 10 via wireless communication so as to be able to communicate bidirectionally, and transmits and receives various data including predetermined data to and from the CGWECU 10, for example.

[0078] The wired communication unit 52 is a communication interface that connects to the CGWECU10 via wired communication using a communication bus B (see Figure 2) or the like to enable bidirectional communication, and transmits and receives various data including, for example, confirmation signals (response signals) to and from the CGWECU10.

[0079] The control unit 60 includes a transmission / reception unit 61 and a processing unit 62, and includes, for example, a computer having a CPU, ROM, RAM, a hard disk drive, input / output ports, and various other circuits. The CPU of the computer functions as the transmission / reception unit 61 and processing unit 62 of the control unit 60, for example, by reading and executing a program stored in the ROM. Furthermore, at least some or all of the transmission / reception unit 61 and processing unit 62 of the control unit 60 can be configured using hardware such as an ASIC or FPGA.

[0080] The storage unit 70 is configured with a storage device such as a nonvolatile memory, a data flash, a hard disk drive, etc. The storage unit 70 stores various programs and the like.

[0081] The transmitter / receiver 61 of the control unit 60 generates a confirmation signal when it receives the predetermined data transmitted from the CGWECU 10. More specifically, when it receives the predetermined data transmitted by wireless communication from the CGWECU 10 via the wireless communication unit 51, it generates a response signal (confirmation signal).

[0082] The transmitter / receiver 61 then transmits (replies to) the generated response signal via wired communication to the CGWECU10 at a predetermined timing. The predetermined timing is set, for example, to the timing at which the in-vehicle ECU 50 transmits data to the CGWECU10. Such data is data different from the response signal, and is, for example, data used by the CGWECU10, or data transmitted to and used by another in-vehicle ECU 50 via the CGWECU10, but is not limited to these.

[0083] In this way, the transmitter / receiver 61 transmits the response signal together with the data at the timing when the data is transmitted by wired communication. Note that the predetermined timing is not limited to the timing when the data is transmitted as described above, and can be set to any timing.

[0084] As described above, the CGWECU10 accepts a response signal for a predetermined period of time after transmitting the specified data, but if there is no data to transmit to the CGWECU10 before the predetermined period has elapsed, the transceiver unit 61 may transmit only the response signal to the CGWECU10 via wired communication.

[0085] In the above, the transceiver unit 61 is configured to receive specified data transmitted by wireless communication from the CGWECU10, but it can also generate a response signal and transmit (reply) it to the CGWECU10 when it receives specified data transmitted by wired communication from the CGWECU10.

[0086] The processing unit 62 executes various processes relating to the control of the vehicle based on the received predetermined data.

[0087] <Control process of CGWECU according to the first embodiment> Next, a specific processing procedure in the CGWECU (communication device) 10 will be described with reference to Fig. 5. Fig. 5 is a flowchart showing the processing procedure executed by the CGWECU (communication device) 10.

[0088] 5, the control unit 20 of the CGWECU 10 acquires predetermined data to be transmitted to the in-vehicle ECU 50 (step S10). Next, the control unit 20 transmits the predetermined data to the in-vehicle ECU 50 by wireless communication (step S11).

[0089] Next, the control unit 20 receives response signals from the in-vehicle ECUs 50 for a predetermined period of time (step S12). Next, the control unit 20 calculates a response rate of the response signals and determines whether the calculated response rate is 100% (step S13). That is, the process of step S13 is a process of determining whether response signals have been returned from all of the in-vehicle ECUs 50 to which the predetermined data was transmitted.

[0090] If the response rate of the response signals is 100% (Yes at step S13), the control unit 20 ends the process and waits until the next timing to start the process of transmitting new predetermined data.

[0091] On the other hand, if the response rate of the response signal is not 100% (step S13, No), the control unit 20 then determines whether the response rate of the response signal is equal to or less than a predetermined value and whether there is a transmission margin time (step S14).

[0092] If the response rate of the response signal is equal to or less than the predetermined value and there is sufficient transmission time (step S14, Yes), the control unit 20 retransmits the predetermined data to the in-vehicle ECU 50 by wireless communication (step S15). Then, the control unit 20 returns to the process of step S12 and performs a process of waiting for a response signal to be returned from the in-vehicle ECU 50.

[0093] On the other hand, if the response signal return rate is not below the predetermined value, or if there is no transmission time (step S14, No), the control unit 20 determines whether the transmission of the specified data via wired communication satisfies the abnormality response processing conditions (step S16).

[0094] When the control unit 20 executes the process of step S16 for the first time, the control unit 20 determines that the abnormality response process condition is not satisfied because the predetermined data has not been transmitted by wired communication (step S16, No), and transmits the predetermined data by wired communication to the in-vehicle ECU 50 that has not received (returned) a response signal (step S17).The control unit 20 then returns to the process of step S12 and performs a process of waiting for a response signal to be returned from the in-vehicle ECU 50.

[0095] Next, if the control unit 20 determines that the transmission of the specified data via wired communication satisfies the abnormality response processing conditions (step S16, Yes), in other words, if the transmission or reception of the specified data is not performed normally even when the specified data is transmitted via wired communication, it executes abnormality response processing (step S18) and terminates the processing.

[0096] As described above, the CGWECU (an example of a communication device) 10 according to the first embodiment is configured to be able to communicate with the in-vehicle ECU (an example of a receiving device) 50. The CGWECU 10 also includes a communication control unit 22 that transmits predetermined data to the in-vehicle ECU 50 via wireless communication and receives a confirmation signal (a response signal) regarding confirmation of the transmission and reception (more specifically, reception) of the predetermined data via wired communication. This reduces the communication load in wired communication.

[0097] (Second embodiment) Next, a second embodiment will be described with reference to Fig. 2. In the following, the same components as those in the first embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

[0098] 2, in the communication system 1, a plurality of in-vehicle ECUs 50 are connected via a communication bus B to enable wired communication. In the second embodiment, the communication system 1 is configured to reduce the communication load in wired communication between the plurality of in-vehicle ECUs 50.

[0099] In the following description, as an example, it is assumed that the in-vehicle ECU 50b1 of the multiple in-vehicle ECUs 50 transmits data, and the in-vehicle ECU 50b1 is referred to as the "transmitting ECU 50b1." Furthermore, it is assumed that the in-vehicle ECU 50b2 receives the data transmitted from the transmitting ECU 50b1, and the in-vehicle ECU 50b2 is referred to as the "receiving ECU 50b2." In the second embodiment, the transmitting ECU 50b1 is an example of a communication device, and the receiving ECU 50b2 is an example of a receiving device.

[0100] In the following description, the transmitting ECU 50b1 will be described as having a function of transmitting data, and the receiving ECU 50b2 will be described as having a function of receiving data. However, this is for ease of understanding and is not intended to be limiting. That is, the in-vehicle ECU 50b2 may transmit data, in which case the in-vehicle ECU 50b2 functions as a "transmitting ECU." Also, the in-vehicle ECU 50b1 may receive data transmitted from the in-vehicle ECU 50b2, in which case the in-vehicle ECU 50b1 functions as a "receiving ECU." That is, each of the multiple in-vehicle ECUs 50 may be configured to have the functions of both a "transmitting ECU" and a "receiving ECU."

[0101] <Configuration of the sending ECU> First, the configuration of the transmitting-side ECU 50b1 will be specifically described with reference to Fig. 6. Fig. 6 is a block diagram showing an example of the configuration of the transmitting-side ECU 50b1 according to the second embodiment. As shown in Fig. 6, the transmitting-side ECU 50b1 includes a wireless communication unit 51, a wired communication unit 52, a control unit 60b1, and a storage unit 70b1.

[0102] The wireless communication unit 51 is a communication interface that is connected to the receiving-side ECU 50b2 via wireless communication so as to be able to communicate bidirectionally, and transmits and receives various data including predetermined data to and from the receiving-side ECU 50b2, for example.

[0103] The wired communication unit 52 is a communication interface that connects to the receiving ECU 50b2 via wired communication using a communication bus B (see Figure 2) or the like to enable bidirectional communication, and transmits and receives various data including confirmation signals between the receiving ECU 50b2 and the receiving ECU 50b2.

[0104] The control unit 60b1 includes an acquisition unit 61b1 and a communication control unit 62b1, and includes, for example, a computer having a CPU, ROM, RAM, a hard disk drive, input / output ports, and various other circuits. The CPU of the computer functions as the acquisition unit 61b1 and communication control unit 62b1 of the control unit 60b1, for example, by reading and executing a program stored in the ROM. In addition, at least some or all of the acquisition unit 61b1 and communication control unit 62b1 of the control unit 60b1 can be configured using hardware such as an ASIC or FPGA.

[0105] The storage unit 70b1 is a storage unit configured with a storage device such as a nonvolatile memory, a data flash, a hard disk drive, etc. The storage unit 70b1 stores predetermined data 71b1 and various programs.

[0106] The predetermined data 71b1 is data to be transmitted to the receiving-side ECU 50b2. The predetermined data 71b1 includes, for example, relatively important data (such as the brake state) to which a confirmation signal is attached, but is not limited to this. Here, the confirmation signal in the second embodiment is an authentication signal (for example, a MAC (Message Authentication Code)) for the receiving-side ECU 50b2 to confirm the authenticity of the predetermined data, in other words, a signal related to confirmation of transmission and reception (more specifically, transmission) of the predetermined data.

[0107] Acquisition unit 61b1 of control unit 60b1 acquires predetermined data. Acquisition unit 61b1 stores the acquired data in storage unit 70b1 as predetermined data 71b1. For example, when acquiring the brake state as the predetermined data, acquisition unit 61b1 acquires a signal indicating the brake state from sensor 100b (see FIG. 2) and stores the acquired brake state in storage unit 70b1 as predetermined data 71b1.

[0108] The communication control unit 62b1 transmits predetermined data to the receiving-side ECU 50b2 via wireless communication and transmits an authentication signal (confirmation signal) for the predetermined data via wired communication. For example, the communication control unit 62b1 reads predetermined data 71b1 from the storage unit 70b1, transmits the read data via wireless communication unit 51, and transmits an authentication signal for confirming the authenticity of the predetermined data via wired communication unit 52.

[0109] The transmission of the predetermined data and authentication signal will be described in detail with reference to Fig. 7. Fig. 7 is a diagram for explaining the transmission of the predetermined data and authentication signal. In Fig. 7, the upper part shows a comparative example in which the predetermined data and authentication signal are both transmitted by wired communication, and the lower part shows an example in the second embodiment in which the predetermined data is transmitted by wireless communication and the authentication signal is transmitted by wired communication.

[0110] 7, the transmission data Da in the comparative example includes a header, predetermined data, and an authentication signal (MAC), and is transmitted via wired communication. If all of the transmission data Da from the transmitting-side ECU 50b1 to the receiving-side ECU 50b2 is transmitted via wired communication in this manner, the amount of data communication on the communication bus B (see FIG. 2) increases, and the communication load in the wired communication increases.

[0111] Therefore, in the second embodiment, as shown in the lower part of Figure 7, the transmission data Da is divided into transmission data D1 including a header, specified data, and an index value, and transmission data D2 including an index value and an authentication signal, and the transmission data D1 is transmitted via wireless communication and the transmission data D2 is transmitted via wired communication.

[0112] The index value is information that links the transmission data D1 and the transmission data D2. That is, the receiving ECU 50b2 can link and associate the transmission data D1 and the transmission data D2 by comparing the index value included in the transmission data D1 with the index value included in the transmission data D2. The index value can be, but is not limited to, a time (for example, a transmission time) or a timer value of the transmitting ECU 50b1. The data communication volume of the index value is assumed to be smaller than the data communication volume of the predetermined data and the header.

[0113] In this way, in the second embodiment, the transmission data D1 including the predetermined data to the receiving ECU 50b2 is performed by wireless communication, and the transmission data D2 including the authentication signal is performed by wired communication. This makes it possible to reduce the communication load in the wired communication by the amount of data communication of the predetermined data (more precisely, by the amount of data communication of the predetermined data and the header) compared to, for example, a comparative example in which the transmission of the predetermined data is performed by wired communication.

[0114] 6, the communication control unit 62b1 transmits the authentication signal as a confirmation signal to the receiving ECU 50b2 as described above. As a result, the receiving ECU 50b2 receives the authentication signal and can confirm the validity of the predetermined data associated with the authentication signal.

[0115] In some cases, for example, the receiving ECU 50b2 may not receive either the transmission data D1 or the transmission data D2 due to some problem. In such a case, the receiving ECU 50b2 requests retransmission of the transmission data D1 including the predetermined data that has not been received or the transmission data D2 including the authentication signal that has not been received.

[0116] Therefore, when a request for retransmission is made by the receiving ECU 50b2, in other words, when the corresponding specified data (transmission data D1) and authentication signal (transmission data D2) have not been received by the receiving ECU 50b2, the communication control unit 62b1 retransmits the unreceived specified data (transmission data D1) or the unreceived authentication signal (transmission data D2) to the receiving ECU 50b2.

[0117] This allows the receiving ECU 50b2 to receive the predetermined data or the authentication signal that has not been received.

[0118] For example, if the receiving ECU 50b2 does not receive the predetermined data even after the predetermined data has been retransmitted, the communication control unit 62b1 may assume that a problem has occurred in the wireless communication and may transmit the predetermined data via wired communication. For example, if the receiving ECU 50b2 does not receive the authentication signal even after the authentication signal has been retransmitted, the communication control unit 62b1 may assume that a problem has occurred in the wired communication and may transmit the authentication signal via wireless communication. This increases the likelihood that the receiving ECU 50b2 will successfully receive the predetermined data or the authentication signal.

[0119] <Configuration of the receiving ECU> Next, the configuration of the receiving-side ECU 50b2 will be specifically described with reference to Fig. 8. Fig. 8 is a block diagram showing an example of the configuration of the receiving-side ECU 50b2 according to the second embodiment. As shown in Fig. 8, the receiving-side ECU 50b2 includes a wireless communication unit 51, a wired communication unit 52, a control unit 60b2, and a storage unit 70b2.

[0120] The wireless communication unit 51 is a communication interface that is connected to the transmitting ECU 50b1 via wireless communication so as to be able to communicate bidirectionally, and transmits and receives various data including predetermined data to and from the transmitting ECU 50b1, for example.

[0121] The wired communication unit 52 is a communication interface that is connected to the transmitting ECU 50b1 via wired communication using a communication bus B (see Figure 2) or the like to enable bidirectional communication, and transmits and receives various data including, for example, a confirmation signal (authentication signal) to and from the transmitting ECU 50b1.

[0122] The control unit 60b2 includes a transceiver 61b2 and a processing unit 62b2, and includes, for example, a computer having a CPU, ROM, RAM, a hard disk drive, input / output ports, and various other circuits. The computer's CPU functions as the transceiver 61b2 and processing unit 62b2 of the control unit 60b2, for example, by reading and executing a program stored in the ROM. In addition, at least some or all of the transceiver 61b2 and processing unit 62b2 of the control unit 60b2 can be configured using hardware such as an ASIC or FPGA.

[0123] The storage unit 70b2 is configured with a storage device such as a nonvolatile memory, a data flash, a hard disk drive, etc. Various programs and the like are stored in the storage unit 70b2.

[0124] The transmitter / receiver 61b2 of the control unit 60b2 receives, via the wireless communication unit 51, transmission data D1 including predetermined data transmitted from the transmitting-side ECU 50b1. The transmitter / receiver 61b2 also receives, via the wired communication unit 52, transmission data D2 including an authentication signal transmitted from the transmitting-side ECU 50b1.

[0125] The transmitter / receiver 61b2 compares the index value included in the transmission data D1 with the index value included in the transmission data D2, and if they match, associates the transmission data D1 with the transmission data D2.

[0126] Furthermore, the transmitting / receiving unit 61b2 confirms the authenticity of the predetermined data associated with the authentication signal based on the authentication signal, and outputs the predetermined data whose authenticity has been confirmed to the processing unit 62b2.

[0127] In addition, when the transmitter / receiver unit 61b2 receives one of the specified data and the authentication signal, but does not receive the corresponding specified data (transmission data D1) and authentication signal (transmission data D2), the transmitter / receiver unit 61b2 requests the transmitting side ECU 50b1 to retransmit the transmission data D1 including the specified data that has not been received, or the transmission data D2 including the authentication signal that has not been received.

[0128] The processing unit 62b2 executes various processes relating to vehicle control based on the predetermined data whose normality has been confirmed.

[0129] <Control process of communication system according to second embodiment> Next, a processing procedure executed by the communication system 1 according to the second embodiment will be described with reference to Fig. 9. Fig. 9 is a diagram showing an example of a processing sequence executed by the communication system 1 according to the second embodiment.

[0130] 9, the control unit 60b1 of the transmitting ECU 50b1 acquires predetermined data to be transmitted to the receiving ECU 50b2 (step S20). Next, the control unit 60b1 transmits the predetermined data (transmission data D1) by wireless communication and transmits an authentication signal (transmission data D2) by wired communication (step S21).

[0131] Next, the control unit 60b2 of the receiving-side ECU 50b2 performs a reception determination process to determine whether the corresponding predetermined data (transmission data D1) and authentication signal (transmission data D2) have been received (step S22). If it is determined that the corresponding predetermined data and authentication signal have been received, the control unit 60b2 performs various processes related to vehicle control using the predetermined data, as described above.

[0132] If the corresponding predetermined data and authentication signal have not been received, the control unit 60b2 requests the transmitting side ECU 50b1 to retransmit the unreceived predetermined data or the unreceived authentication signal (step S23).

[0133] When the request for retransmission is made, the receiving-side ECU 50b2 retransmits the unreceived predetermined data or the unreceived authentication signal to the receiving-side ECU 50b2 (step S24).

[0134] In this way, the transmitting ECU 50b1 (an example of a communication device) according to the second embodiment is configured to be able to communicate with the receiving ECU 50b2 (an example of a receiving device). The transmitting ECU 50b1 also includes a communication control unit 62b1 that transmits predetermined data to the receiving ECU 50b2 via wireless communication and transmits a confirmation signal (authentication signal) for confirming the transmission and reception (more specifically, transmission) of the predetermined data via wired communication. This reduces the communication load in wired communication.

[0135] Furthermore, in the first and second embodiments described above, data for confirming whether or not predetermined data has been transmitted and received (for example, a confirmation signal (a response signal or an authentication signal)) is transmitted via wired communication, so that the information on whether or not transmission and reception has occurred and the confirmation information is transmitted reliably. That is, for example, if the information on whether or not transmission and reception has occurred and the confirmation information were transmitted wirelessly, in a noisy environment or the like, it may become unclear whether or not the actual data has been transmitted, and this may result in confusion or unnecessary retransmissions or other processing (for example, a situation may arise in which the confirmation signal is not transmitted even though the data has been received correctly). In the first and second embodiments, by using wired communication as described above, it is possible to prevent such an occurrence.

[0136] Furthermore, when a wireless-wireless loop is used, both paths are susceptible to noise and other factors. Therefore, when a data transmission / reception error or the like occurs, it is unclear which wireless path the error occurred on, or in other words, it is difficult to estimate, and it may be difficult to take appropriate action. In the first and second embodiments, a wireless-wired loop is used, so it is possible to almost certainly estimate that the error is wireless.

[0137] In each of the above-described embodiments, the CGWECU 10 and the in-vehicle ECU 50 are communicatively connected by a communication bus B, but this is not limited thereto, and they may be communicatively connected by, for example, power line communication (PLC (Power Line Communication)).

[0138] Furthermore, in the first embodiment described above, when a response signal is not received, the specified data is transmitted by wired communication only to the vehicle-mounted ECU 50 that does not receive the response signal, but this is not limited to this, and for example, the specified data may also be transmitted by wired communication to the vehicle-mounted ECU 50 that has received the response signal.

[0139] In addition, in the second embodiment described above, the specified data is transmitted via wireless communication and the authentication signal is transmitted via wired communication, but this is not limited to this. For example, some or all of the specified data may be transmitted via wired communication and some or all of the authentication signal may be transmitted via wireless communication.

[0140] Further advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0141] 1. Communication Systems 10 CGWECU 50 Automotive ECU 22,62b1 Communication control unit

Claims

1. A communication device capable of communicating with a receiving device, the communication device having a control unit, The control unit transmitting predetermined data to the receiving device via wireless communication; receiving a response signal from the receiving device via wired communication to confirm that the predetermined data has been received by the receiving device; If the response signal is not received, the predetermined data is transmitted to the receiving device via wired communication. Communication equipment.

2. the receiving device is a plurality of devices, The control unit transmitting the predetermined data to the plurality of receiving devices simultaneously via wireless communication; The communication device according to claim 1 .

3. A communication method performed by a communication device, transmitting predetermined data to a receiving device via wireless communication; receiving a response signal from the receiving device via wired communication to confirm that the predetermined data has been received by the receiving device; If the response signal is not received, the predetermined data is transmitted to the receiving device via wired communication. Communication method.

Images