Vehicle-mounted terminal time synchronization system and synchronization method

Abstract

The invention provides a vehicle-mounted terminal time synchronization system and a synchronization method, the system comprises a plurality of domain controllers and a plurality of vehicle-mounted terminals, the plurality of domain controllers are mutually connected to form a vehicle-mounted Ethernet, the plurality of vehicle-mounted terminals are respectively connected to one of the plurality of domain controllers, each vehicle-mounted terminal comprises a physical layer, a plurality of domain controllers, a plurality of domain controllers and a plurality of domain controllers, the physical layer is synchronized with a master clock device through an Ethernet interface, and the physical layer is used for generating a whole-network absolute timestamp; the data link layer is connected to the physical layer and used for calling the whole network absolute timestamp generated by the physical layer; and the processor is connected to the data link layer and is used for calling a whole-network absolute timestamp corresponding to the vehicle-mounted terminal data through the data link layer when the vehicle-mounted terminal data is sent, packaging the vehicle-mounted terminal data and the whole-network absolute timestamp into an Ethernet message and sending the Ethernet message through the Ethernet interface. And time synchronization and multi-domain transmission of the vehicle-mounted terminal are realized.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a vehicle-mounted terminal time synchronization system and synchronization method. Background Art

[0002] The in-vehicle network system is usually divided into power domain, chassis domain, intelligent information domain, autonomous driving domain and body domain, but the controllers of different domains are arranged and connected by wire harnesses in a physically isolated manner, and the in-vehicle network system cannot achieve multi-domain mixed transmission.

[0003] Since the device levels in different domains cannot be synchronized in time, information from different domains cannot be transmitted in the same network architecture. Therefore, the sensor information obtained by the autonomous driving domain and the intelligent information domain cannot be determined as external information at the same time, affecting real-time road condition judgment. Summary of the invention

[0004] Based on this, it is necessary to provide a vehicle terminal time synchronization system and synchronization method to address the problems in the above background technology, so as to achieve full network time synchronization of the vehicle network.

[0005] To achieve the above-mentioned purpose and other related purposes, one aspect of the present application provides a vehicle terminal time synchronization system, comprising a plurality of domain controllers and a plurality of vehicle terminals, wherein the plurality of domain controllers are interconnected to form a vehicle Ethernet, the plurality of vehicle terminals are respectively connected to one of the plurality of domain controllers, and each of the vehicle terminals comprises:

[0006] The physical layer is synchronized with the master clock device via an Ethernet interface and is used to generate an absolute timestamp for the entire network;

[0007] The data link layer is connected to the physical layer and is used to retrieve the network-wide absolute timestamp generated by the physical layer;

[0008] The processor is connected to the data link layer, and is used to retrieve the network-wide absolute timestamp corresponding to the vehicle-mounted terminal data via the data link layer when sending the vehicle-mounted terminal data, and package the vehicle-mounted terminal data and the network-wide absolute timestamp into an Ethernet message and send it via the Ethernet interface.

[0009] In one embodiment, the processor is further configured to receive an Ethernet message via the Ethernet interface, and parse the Ethernet message to obtain vehicle-mounted terminal data and a network-wide absolute timestamp corresponding to the vehicle-mounted terminal data.

[0010] In one embodiment, the processor is further configured to process the vehicle-mounted terminal data corresponding to the network-wide absolute timestamp based on the network-wide absolute timestamp.

[0011] In one embodiment, the master clock device is one of the plurality of domain controllers.

[0012] In one embodiment, the multiple domain controllers are synchronized to the master clock device based on a generalized clock synchronization protocol.

[0013] In one embodiment, the vehicle-mounted terminal includes one or more of a camera, a radar, a motor, a chassis steering system, a central control screen, and a central computing unit.

[0014] In one embodiment, the vehicle-mounted terminal further includes a data generating module for generating the vehicle-mounted terminal data, and the processor is connected to the data generating module to obtain the vehicle-mounted terminal data.

[0015] In one embodiment, the vehicle-mounted terminal data includes vehicle-mounted terminal information and / or vehicle-mounted terminal instructions.

[0016] Another aspect of the present invention provides a vehicle terminal time synchronization method, comprising:

[0017] Synchronize with the master clock device to generate an absolute timestamp for the entire network;

[0018] Obtain vehicle terminal data, and retrieve the network-wide absolute timestamp corresponding to the vehicle terminal data;

[0019] The vehicle terminal data and the network-wide absolute timestamp are packaged into an Ethernet message and sent.

[0020] In one embodiment, the vehicle terminal time synchronization method further includes:

[0021] An Ethernet message is received, and the Ethernet message is parsed to obtain vehicle terminal data and a network-wide absolute timestamp corresponding to the vehicle terminal data.

[0022] According to the vehicle terminal time synchronization system and synchronization method provided by the present invention, the vehicle terminal is networked through the Ethernet switching function of the domain controller, and the domain controller is synchronized with the master clock. When the vehicle terminal needs to send vehicle terminal data, the whole network absolute timestamp corresponding to the vehicle terminal data is retrieved, and the vehicle terminal data and the corresponding whole network absolute timestamp are packaged into Ethernet messages and sent. The time of the corresponding vehicle terminal data is determined by the whole network absolute timestamp to achieve vehicle terminal time synchronization. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to better describe and illustrate the embodiments and / or examples of those applications disclosed herein, reference may be made to one or more drawings. The additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed applications, the embodiments and / or examples currently described, and the best modes of these applications currently understood.

[0024] Figure 1 It is a structural schematic diagram of a vehicle terminal time synchronization system provided in an embodiment;

[0025] Figure 2 is a schematic structural diagram of a vehicle-mounted terminal provided in an embodiment;

[0026] Figure 3 The present invention is a flowchart of a vehicle terminal time synchronization method provided in an embodiment.

[0027] Description of reference numerals:

[0028] 11. First domain controller; 12. Second domain controller; 13. Third domain controller; 110. Ethernet interface; 120. Physical layer; 130. Data link layer; 140. Processor; 150. Data generation module; 21A. First camera; 21B. Second camera; 22A. First radar; 22B. Second radar; 23A. First motor; 23B. Second motor; 24. Chassis steering system; 25. Central control screen; 26. Central computing unit. DETAILED DESCRIPTION

[0029] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are given in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0031] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present application. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0032] It should be noted that the illustrations provided in this embodiment only illustrate the basic concept of the present application in a schematic manner. Although the illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation, the type, quantity and proportion of each component in actual implementation may be changed arbitrarily, and the component layout type may also be more complicated.

[0033] Aiming at the problem that the current vehicle network system cannot realize time synchronization and multi-domain hybrid transmission, the present invention provides a vehicle terminal time synchronization system, such as Figure 1 and Figure 2 As shown, it includes multiple domain controllers and multiple vehicle terminals, the multiple domain controllers are interconnected to form a vehicle Ethernet, the multiple vehicle terminals are respectively connected to one of the multiple domain controllers, and each of the vehicle terminals includes:

[0034] Physical layer 120, which is synchronized with the master clock device via Ethernet interface 110 and is used to generate an absolute timestamp for the entire network;

[0035] The data link layer 130 is connected to the physical layer 120 and is used to retrieve the network-wide absolute timestamp generated by the physical layer;

[0036] The processor 140 is connected to the data link layer 130, and is used to retrieve the network-wide absolute timestamp corresponding to the vehicle-mounted terminal data via the data link layer when sending the vehicle-mounted terminal data, and package the vehicle-mounted terminal data and the network-wide absolute timestamp into an Ethernet message and send it via the Ethernet interface.

[0037] In one embodiment, the vehicle terminal time synchronization system includes a plurality of domain controllers, and the plurality of domain controllers are connected to each other to form a vehicle Ethernet. Figure 1 As shown, the vehicle terminal time synchronization system includes a first domain controller 11, a second domain controller 12 and a third domain controller 13, wherein the first domain controller 11 is connected to the second domain controller 12, the second domain controller 12 is connected to the third domain controller 13, and the third domain controller 13 is connected to the first domain controller 11, thereby forming a vehicle Ethernet.

[0038] In one embodiment, multiple vehicle terminals are networked through the Ethernet switching function of the domain controller. Specifically, each vehicle terminal is connected to one of the domain controllers. The vehicle terminal includes but is not limited to at least one of a camera, a radar, a motor, a chassis steering system, a central control screen, and a central computing unit. Figure 1As shown, the vehicle terminal connected to the first domain controller 11 includes a first camera 21A, a first radar 22A and a first motor 23A, the vehicle terminal connected to the second domain controller 12 includes a second camera 21B, a second radar 22B and a second motor 23B, and the vehicle terminal connected to the third domain controller 13 includes a chassis steering system 24, a central control screen 25 and a central computing unit 26. It should be noted that the above vehicle terminals are only exemplary, and the vehicle terminals may also include other vehicle devices connected to any domain controller.

[0039] In one embodiment, each vehicle terminal includes an Ethernet interface 110, a physical layer 120, a data link layer 130, a processor 140, and a data generation module 150. The Ethernet interface 110 is a physical interface, and the vehicle terminal is connected to one of the domain controllers through the Ethernet interface 110.

[0040] The physical layer 120 is also called a physical interface transceiver (PHY), and the physical layer 120 is connected to the Ethernet interface 110. The physical layer includes a media independent interface (MII / GMII) sublayer, a physical coding (PCS) sublayer, a physical medium attachment (PMA) sublayer, a physical medium dependent (PMI) sublayer, and a medium dependent interface (MDI) sublayer. When the physical layer sends data, it receives the data sent by the data link layer, and then converts the parallel data into serial stream data, and then encodes the data according to the encoding rules of the physical layer, converts it into an analog signal and sends it out. The process of receiving data is the opposite.

[0041] The data link layer 130 includes a media access control (MAC) sublayer and a logical link control (LLC) sublayer. The data link layer 130 is connected to the physical layer 120. The MAC (Media Access Control) protocol is mainly responsible for controlling the physical medium connected to the physical layer. When sending data, the MAC protocol can determine in advance whether the data can be sent. If it can be sent, it will add control information to the data and finally send the data and control information to the physical layer 120 in a specified format. When receiving data, the MAC protocol first determines whether the input information has a transmission error. If there is no error, the above control information is removed and the data is sent to the logical link control sublayer.

[0042] The processor 140 includes but is not limited to a central processing unit (CPU), a graphics processing unit (GPU), and a digital signal processor (DSP). The processor 140 is connected to the data link layer 130. The data generation module 150 is used to generate vehicle terminal data, such as vehicle terminal information and / or vehicle terminal instructions. The processor 140 is connected to the data generation module 150 to obtain vehicle terminal data.

[0043] In one embodiment, the vehicle terminal synchronization system performs time synchronization by first selecting a clock source, such as one of the domain controllers as the master clock device, and other domain controllers in the system perform time synchronization with the master clock device. The synchronization method can adopt the generalized time and space protocol (gPTP). Figure 1 As shown, the first domain controller 11 is selected as the master clock device, and the second domain controller 12 and the third domain controller 13 perform time synchronization with the first domain controller 11 based on the generalized time synchronization protocol (gPTP).

[0044] The purpose of the Generalized Precision Time Protocol (gPTP) is to synchronize the clocks of various devices in the vehicle network. Because the clocks of various devices run independently of each other, and some applications require the devices to execute in unison, the two devices must have the same clock reference. The gPTP protocol is based on a master-slave relationship, that is, all devices in a local network use the clock of the master as the reference, and the slave synchronizes its local clock with the clock of the master. Clock synchronization is progressive, and the slave device can also be used as a device in the next layer of the network.

[0045] The process of time synchronization based on the generalized time and space protocol (gPTP) mainly includes the selection of the best master clock, frequency deviation measurement, delay time measurement, time synchronization and other stages.

[0046] In the best master clock selection stage, the best master clock algorithm (BMCA) is usually used. All devices send messages and compare their own related field values ​​with those in other stages. The winner is used as the master clock device. However, the in-vehicle Ethernet is a closed network, and the devices usually do not change, so the master clock device is usually fixed. Specifically, the first domain controller 11 is used as the master clock device.

[0047] During the frequency synchronization phase, the frequencies of the clocks of various devices in the vehicle network are not always completely consistent, so the clock frequency of the slave device needs to match that of the master device. The master device continuously sends synchronization messages (Sync) and follow-up messages (Follow-up), and the slave device (slave) can measure the time when it receives the synchronization message (based on the local clock of the slave device). After each synchronization message, the master device will also send a follow-up message to tell the slave device the timestamp of a synchronization message (based on the local clock of the master device), and the slave device (slave) can calculate the deviation between its own clock frequency and the master device. Specifically, the first domain controller 11, as the master device, sends synchronization messages (Sync) and follow-up messages (Follow-up) to the second domain controller 12 and the third domain controller 13, and the second domain controller 12 and the third domain controller 13 calculate the deviation between their own clock frequencies and the first domain controller 11.

[0048] In the delay time measurement phase, in order to synchronize its own clock with the master device, the slave device needs to measure the delay time of the message transmission between itself and the master device. The slave device first sends a delay request message (PDelay_Req) ​​and obtains the first timestamp when the message leaves the physical layer of the slave device. When the master device receives the message, it obtains the second timestamp when the message arrives at the physical layer of the master device. The master device sends a delay response message (PDelay_Resp) to bring the second timestamp to the slave device. The master device also sends a delay response follow-up message (PDelay_Resp_Follow-up) to tell the slave device the third timestamp of a delay response message (PDelay_Resp). The slave device (slave) can measure the fourth timestamp of the delay response message (PDelay_Resp) it receives. The slave device calculates the delay time based on the first timestamp, the second timestamp, the third timestamp, and the fourth timestamp. Specifically, the second domain controller 12 and the third domain controller 13, as slave devices, send delay request messages to the first domain controller 11. After receiving the messages, the first domain controller 11 sends a delay response message and a delay response follow-up message. The second domain controller 12 and the third domain controller 13 calculate the delay time with the first domain controller 11 based on the corresponding timestamps.

[0049] After calculating the frequency difference and delay time, the slave device can synchronize its own clock with the master device. In one embodiment, the first domain controller 11 is used as the master clock device, and the second domain controller 12 and the third domain controller 13 are used as slave devices. The second domain controller 12 and the third domain controller 13 respectively calculate the clock frequency deviation and delay time with the first domain controller 11 through the above process, and then synchronize their own clocks with the first domain controller 11, so as to achieve time synchronization of the first domain controller 11, the second domain controller 12, and the third domain controller 13.

[0050] In one embodiment, referring to Figure 2 As shown, the on-board terminal time synchronization first synchronizes the physical layer 120 with the master clock device and stores the current clock; when the on-board terminal needs to send information or instructions and other on-board terminal data, the processor 140 performs hardware time packaging, and the processor retrieves the network-wide absolute timestamp in the physical layer 120 through the data link layer 130, and encapsulates the time corresponding to the on-board terminal data in the Ethernet message, and sends it out through the Ethernet interface 110. Further, the processor is also used to receive Ethernet messages via the Ethernet interface, parse the Ethernet messages to obtain the on-board terminal data and the network-wide absolute timestamp corresponding to the on-board terminal data. Further, the processor is also used to process the on-board terminal data corresponding to the network-wide absolute timestamp based on the network-wide absolute timestamp.

[0051] In one embodiment, referring to Figure 1 and Figure 2 As shown, the vehicle-mounted terminal is connected to the domain controller via the Ethernet interface 110. Since the domain controller has achieved time synchronization, the physical layer 120 of each vehicle-mounted terminal can store the current clock of the domain controller, that is, the clock of the entire network after the domain controller time is synchronized. The physical layer 120 can also further generate an absolute timestamp for the entire network.

[0052] In one embodiment, the vehicle terminal includes but is not limited to at least one of a camera, a radar, a motor, a chassis steering system, a central control screen, and a central computing unit. Taking the first camera 21A sending data to the central control screen 25 as an example, the first camera 21A is connected to the first domain controller 11, and the central control screen 25 is connected to the third domain controller 13. The data that the first camera 21A needs to send is video data. The processor 140 of the first camera 21A obtains the video data from the data generation module 150 of the first camera 21A, and retrieves the network-wide absolute timestamp corresponding to the video data of the first camera 21A in the physical layer 120 through the data link layer 130. For example, the network-wide absolute timestamp indicates the time when the video data that the first camera 21A needs to send is generated. The processor encapsulates the video data that the first camera 21A needs to send and the network-wide absolute timestamp corresponding to the video data in an Ethernet message, and sends it to the central control screen 25 via the Ethernet interface 110, the first domain controller 11, and the third domain controller 13. The central control screen 25 receives the Ethernet message from the first camera 21A via its Ethernet interface 110, and the processor of the central control screen 25 parses the Ethernet message to obtain the video data from the first camera 21A and the network-wide absolute timestamp corresponding to the video. Since the vehicle Ethernet has achieved time synchronization, when the time of the network-wide absolute timestamp corresponding to the video data of the first camera 21A obtained by parsing is the first time, the video data from the first camera 21A and the data of the first time determined by the physical layer 120 of the central control screen 25 can be processed as data of the same time. In this way, the time synchronization between the first camera 21A of the vehicle terminal and the central control screen 25 of the vehicle terminal is achieved, and the multi-domain mixing of the autonomous driving domain and the intelligent information domain is also achieved.

[0053] Exemplarily, the central computing unit is further used to receive Ethernet messages via the Ethernet interface, and parse the Ethernet messages to obtain vehicle-mounted terminal data and a network-wide absolute timestamp corresponding to the vehicle-mounted terminal data.

[0054] In one embodiment, taking the first camera 21A and the second camera 21B and sending data to the central computing unit 26 as an example, the first camera 21A is connected to the first domain controller 11, the second camera 21B is connected to the second domain controller 12, and the central computing unit 26 is connected to the third domain controller 13. The data that the first camera 21A and the second camera 21B need to send is video data. The processor of the first camera 21A obtains the video data from the data generation module of the first camera 21A, and retrieves the first network-wide absolute timestamp corresponding to the video data of the first camera 21A in the physical layer 120 through the data link layer 130. The processor encapsulates the video data that the first camera 21A needs to send and the first network-wide absolute timestamp corresponding to the video data in the first Ethernet message, and sends it to the central computing unit 26 through the Ethernet interface 110, the first domain controller 11, and the third domain controller 13. The processor of the second camera 21B obtains the video data from the data generation module of the second camera 21B, and calls the second network-wide absolute timestamp corresponding to the video data of the second camera 21B in the physical layer 120 through the data link layer 130. The processor encapsulates the video data to be sent by the second camera 21B and the second network-wide absolute timestamp corresponding to the video data in a second Ethernet message, and sends it to the central computing unit 26 through the Ethernet interface 110, the first domain controller 11, and the third domain controller 13. The central computing unit 26 receives the first Ethernet message from the first camera 21A and the second Ethernet message from the second camera 21B, and parses the first Ethernet message and the second Ethernet message to obtain the video data from the first camera 21A and the corresponding first full-network absolute timestamp, as well as the video data from the second camera 21B and the corresponding second full-network absolute timestamp. Since the vehicle Ethernet has achieved time synchronization, when the first full-network absolute timestamp and the second full-network absolute timestamp are within the same time range, the central computing unit 26 is also used to process the video data from the first camera 21A and the video data from the second camera 21B as data within the same time range. In this way, the time synchronization between the first camera 21A, the second camera 21B and the central computing unit 26 of the vehicle terminal is achieved, and the multi-domain mixing of the vehicle Ethernet is also achieved.

[0055] According to the vehicle terminal time synchronization system provided by the present invention, the vehicle terminal is networked through the Ethernet switching function of the domain controller, and the domain controller is synchronized with the master clock. When the vehicle terminal needs to send vehicle terminal data, the whole network absolute timestamp corresponding to the vehicle terminal data is retrieved, and the vehicle terminal data and the corresponding whole network absolute timestamp are packaged into an Ethernet message and sent. The time of the corresponding vehicle terminal data is determined by the whole network absolute timestamp to achieve vehicle terminal time synchronization.

[0056] The present invention also provides a vehicle terminal time synchronization method, such as Figure 3 As shown, the following steps are included:

[0057] Step S301: Synchronize with the master clock device to generate an absolute timestamp for the entire network;

[0058] Step S302: Acquire vehicle terminal data, and retrieve the network-wide absolute timestamp corresponding to the vehicle terminal data;

[0059] Step S303: Packaging the vehicle terminal data and the whole network absolute timestamp into an Ethernet message and sending it.

[0060] In one embodiment, referring to Figure 1 As shown, the vehicle terminal time synchronization system includes a first domain controller 11, a second domain controller 12 and a third domain controller 13 for constituting the vehicle Ethernet. When performing vehicle terminal time synchronization, one of the domain controllers is first selected as the clock source, and then the other domain controllers are synchronized to the master clock device, and the synchronization method can adopt the generalized time protocol (gPTP). Specifically, the first domain controller 11 is selected as the master device (master), and the second domain controller 12 and the third domain controller 13 are slave devices (slave). The second domain controller 12 and the third domain controller 13 respectively calculate the clock frequency deviation and delay time with the first domain controller 11 based on the generalized time protocol (gPTP), and then synchronize their own clocks with the first domain controller 11 to achieve time synchronization of the first domain controller 11, the second domain controller 12, and the third domain controller 13. Furthermore, after the domain controllers constituting the in-vehicle Ethernet achieve time synchronization, the physical layer 120 of each in-vehicle terminal is connected to the domain controller via the Ethernet interface 110, and can store the current clock of the domain controller, that is, the clock of the entire network after time synchronization. The physical layer 120 can also further generate an absolute timestamp for the entire network.

[0061] In one embodiment, after each domain controller realizes time synchronization, the processor of the vehicle terminal obtains vehicle terminal data such as information or instructions that the vehicle terminal needs to send, and retrieves the network-wide absolute timestamp corresponding to the vehicle terminal data. Figure 2 As shown, the processor 140 obtains the vehicle terminal data from the data generation module 150 , and retrieves the network-wide absolute timestamp in the physical layer 120 through the data link layer 130 .

[0062] In one embodiment, after obtaining the vehicle terminal data and the network-wide absolute timestamp corresponding to the vehicle terminal data, the vehicle terminal data and the network-wide absolute timestamp are packaged into an Ethernet message and sent. Figure 2As shown, the processor 140 performs hardware time packaging on the vehicle terminal data and the corresponding network-wide absolute timestamp to generate an Ethernet message. The Ethernet message generated by the processor 140 is transmitted to other vehicle terminals via the data link layer 130, the physical layer 120, the Ethernet interface 110 and the first domain controller in sequence. Taking the data sent by the first camera 21A as an example, the first camera 21A is connected to the first domain controller 11, and the data to be sent by the first camera 21A is video data. The processor 140 of the first camera 21A obtains the video data from the data generation module 150 of the first camera 21A, and retrieves the network-wide absolute timestamp corresponding to the video data of the first camera 21A in the physical layer 120 through the data link layer 130. The processor packages the video data to be sent by the first camera 21A and the network-wide absolute timestamp corresponding to the video data in the Ethernet message, and sends it to other vehicle terminals through the Ethernet interface 110 and the first domain controller 11.

[0063] In one embodiment, after sending the Ethernet message, the method further includes receiving the Ethernet message, parsing the Ethernet message to obtain the vehicle terminal data and the whole network absolute timestamp corresponding to the vehicle terminal data, and further determining the processing order of the vehicle terminal data according to the whole network absolute timestamp. Figure 2 As shown, after receiving the Ethernet message from other vehicle terminals, the processor 140 of the vehicle terminal parses the Ethernet message to obtain the vehicle terminal data and the whole network absolute timestamp corresponding to the vehicle terminal data. The vehicle terminal data with the whole network absolute timestamp of the same time or in the same time range can be processed together. Taking the central computing unit 26 receiving the Ethernet message from the first camera 21A and / or the second camera 21B as an example, the processor 140 of the central computing unit 26 parses the Ethernet message to obtain, for example, video data from the first camera 21A and / or the second camera 21B and the corresponding whole network absolute timestamp. When the whole network timestamp of the video data of the first camera 21A is the same as or in the same range as the whole network timestamp of the video data of the second camera 21B, the video data of the first camera 21A is processed together with the video data of the second camera 21B.

[0064] According to the vehicle terminal time synchronization method provided by the present invention, an absolute timestamp for the entire network can be generated based on synchronization with the master clock, and the vehicle terminal data and the corresponding absolute timestamp for the entire network are packaged into Ethernet messages and sent, thereby realizing vehicle terminal time synchronization and multi-domain mixed transmission.

[0065] Please note that the above embodiments are for illustrative purposes only and are not intended to limit the present application.

[0066] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0067] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0068] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application.

Claims

1. A vehicle terminal time synchronization system, characterized in that: The invention comprises a plurality of domain controllers and a plurality of vehicle-mounted terminals, wherein the plurality of domain controllers are interconnected to form a vehicle-mounted Ethernet, the plurality of vehicle-mounted terminals are respectively connected to one of the plurality of domain controllers, and each of the vehicle-mounted terminals comprises: The physical layer is synchronized with the master clock device via an Ethernet interface and is used to generate an absolute timestamp for the entire network; The data link layer is connected to the physical layer and is used to retrieve the network-wide absolute timestamp generated by the physical layer; The processor is connected to the data link layer, and is used to retrieve the network-wide absolute timestamp corresponding to the vehicle-mounted terminal data via the data link layer when sending the vehicle-mounted terminal data, and package the vehicle-mounted terminal data and the network-wide absolute timestamp into an Ethernet message and send it via the Ethernet interface.

2. The vehicle terminal time synchronization system according to claim 1, characterized in that: The processor is further configured to receive an Ethernet message via the Ethernet interface, and parse the Ethernet message to obtain vehicle-mounted terminal data and a network-wide absolute timestamp corresponding to the vehicle-mounted terminal data.

3. The vehicle terminal time synchronization system according to claim 2, characterized in that: The processor is further configured to process the vehicle-mounted terminal data corresponding to the whole-network absolute timestamp based on the whole-network absolute timestamp.

4. The vehicle terminal time synchronization system according to claim 1, characterized in that: The master clock device is one of the multiple domain controllers.

5. The vehicle terminal time synchronization system according to claim 4, characterized in that: The multiple domain controllers are synchronized to the master clock device based on a generalized clock synchronization protocol.

6. The vehicle terminal time synchronization system according to claim 1, characterized in that: The vehicle-mounted terminal includes one or more of a camera, a radar, a motor, a chassis steering system, a central control screen, and a central computing unit.

7. The vehicle terminal time synchronization system according to claim 6, characterized in that: The vehicle-mounted terminal further includes a data generating module for generating the vehicle-mounted terminal data, and the processor is connected to the data generating module to obtain the vehicle-mounted terminal data.

8. The vehicle terminal time synchronization system according to claim 1, characterized in that: The vehicle-mounted terminal data includes vehicle-mounted terminal information and / or vehicle-mounted terminal instructions.

9. A vehicle terminal time synchronization method, characterized in that: include: Synchronize with the master clock device to generate an absolute timestamp for the entire network; Obtain vehicle terminal data, and retrieve the network-wide absolute timestamp corresponding to the vehicle terminal data; The vehicle terminal data and the network-wide absolute timestamp are packaged into an Ethernet message and sent.

10. The vehicle terminal time synchronization method according to claim 9, characterized in that: Also includes: An Ethernet message is received, and the Ethernet message is parsed to obtain vehicle terminal data and a network-wide absolute timestamp corresponding to the vehicle terminal data.

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