CN107733459B - Vehicle-mounted T-Box and its application based on DSRC and low-altitude satellite communication - Google Patents

Abstract

The invention provides a vehicle-mounted T-Box based on DSRC and low-altitude satellite communication, comprising a data acquisition unit and a wireless communication unit connected to each other, the data acquisition unit includes a slave processor, and data storage and CAN communication connected with the slave processor module, the wireless communication unit includes the main processor, and DSRC communication module, 4G communication module, low-altitude satellite communication module, WiFi/BT module, GPS/Beidou positioning module, RTC real-time clock module, battery management unit, storage module, voice module, Codec module, human-computer interaction module and security chip. The invention realizes real-time interaction and sharing of dynamic information between vehicles, vehicles and people, and vehicles and roadside base stations by applying the DSRC communication technology. This full-time and space-based traffic dynamic information collection and fusion technology can realize vehicle safety active risk avoidance control and intelligent collaborative management of roads, and better promote the development of smart transportation.

Description

Vehicle-mounted T-Box and its application based on DSRC and low-altitude satellite communication

technical field

The invention belongs to the technical field of Internet of Vehicles, in particular to a vehicle-mounted T-Box based on DSRC and low-altitude satellite communication.

Background technique

With the development of data communication and multimedia service requirements, a new generation of mobile communication technology that meets the needs of high-speed mobile data transmission, mobile computing and mobile multimedia operations—low-altitude satellite communication technology has begun to emerge. Traditional satellites are far away from the ground, with a distance of 36,000 kilometers. The network delay is large and the connection is slow, so it is not suitable for high-speed network transmission, and the low-altitude satellites are only deployed at 1200 kilometers above the ground, which can replace the ground base station tower. From a high-altitude view, the traditional ground base station The signal propagates almost horizontally, and will be blocked by countless trees and buildings, and eventually the signal will attenuate. However, the transmission of low-altitude satellite signals is from top to bottom, directly connecting users. Therefore, there is reason to expect that this mobile communication technology will bring people a better future.

The traditional vehicle-mounted T-Box uses GPRS system or 4G communication technology to realize vehicle communication. Data transmission is limited by communication signals, and communication cannot be performed in areas with no signal or poor signal. Therefore, a single 4G mobile communication method can no longer meet the needs of future vehicles. The development of networking requires the real-time and reliability of vehicle T-Box data transmission. The emergence of low-altitude satellite communication technology has promoted the further development of the Internet of Vehicles technology. The theoretical value of the transmission speed of 100Mbps can definitely meet the data transmission rate requirements of the Internet of Vehicles. In addition, the general Internet of Vehicles terminal uses clear text transmission when transmitting data, facing the risk of data interception, packet capture, and eavesdropping, resulting in leakage of enterprise-level secrets, and even loss of user life and property. Therefore, the security and reliability of data transmission is very important.

DSRC is Dedicated Short Range Communications (dedicated short-range communication technology) is an efficient wireless communication technology, which can realize the identification and two-way communication of moving targets under high-speed movement in a specific area (usually tens of meters), such as vehicles The "vehicle-road" and "vehicle-vehicle" two-way communication transmits images, voice and data information in real time, and organically connects vehicles and roads. The application of DSRC technology in intelligent transportation system can greatly improve and enhance the efficiency of people's traffic travel.

To sum up, in view of the development of the existing Internet of Vehicles technology and the defects of equipment, there is an urgent need for an Internet of Vehicles terminal with faster transmission speed, higher reliability and security, and more powerful functions to meet the rapid development of intelligent transportation.

Contents of the invention

In view of this, the present invention aims to propose a vehicle-mounted T-Box based on DSRC and low-altitude satellite communication, through the application of DSRC communication technology to realize the real-time interaction and communication of dynamic information between vehicles and vehicles, vehicles and people, vehicles and roadside base stations. shared.

In order to achieve the above object, technical solution of the present invention is achieved in that way:

A vehicle-mounted T-Box based on DSRC and low-altitude satellite communication, comprising interconnected data acquisition units and wireless communication units, the data acquisition unit includes a slave processor, and data storage and CAN communication connected to the slave processor module, the wireless communication unit includes a main processor, and a DSRC communication module connected to the main processor, a 4G communication module, a low-altitude satellite communication module, a WiFi/BT module, a GPS/Beidou positioning module, an RTC real-time clock module, A battery management unit, a storage module, a voice module, a codec module, a human-computer interaction module and a security chip, the main processor and the slave processor are connected through an SPI interface.

Further, the data acquisition unit collects instrument panel information, each ECU status information and fault information of the vehicle through CAN buses on both sides, and sends the collected information to the cloud platform for processing through the 4G communication module in the wireless communication unit, And send the result to the mobile terminal through the WiFi/BT module.

Further, the GPS/Beidou positioning module in the wireless communication unit transmits the location information of the vehicle to the cloud platform or the vehicle dispatching center in real time through the 4G communication module.

Further, the wireless communication unit receives the data from the cloud platform or the user's mobile phone, and converts it into message data that can be recognized by the CAN bus, so as to realize the remote operation of the vehicle.

Compared with the prior art, a vehicle-mounted T-Box based on DSRC and low-altitude satellite communication described in the present invention has the following advantages: the present invention can effectively connect vehicles in motion to the network, especially the introduction of low-altitude satellite communication, It can realize the direct connection between the vehicle on the ground and the satellite in the air, effectively avoid the influence of the communication signal quality caused by the occlusion of buildings or terrain, ensure the reliability and stability of signal transmission, and realize the intra-vehicle network and mobile communication The "high-speed two-way dialogue" of the network, and then realize the remote real-time monitoring of the car on the cloud platform or mobile client, intelligent operation and reasonable scheduling, and realize the communication between vehicles and vehicles, vehicles and people, and vehicles and roadside base stations through the application of DSRC communication technology Real-time interaction and sharing of dynamic information. This full-time and space-based traffic dynamic information collection and fusion technology can realize vehicle safety active risk avoidance control and intelligent collaborative management of roads, and better promote the development of smart transportation.

Another object of the present invention is to propose a vehicle-road coordination system using the vehicle-mounted T-Box to realize real-time interaction and sharing of dynamic information between vehicles, vehicles and people, and vehicles and roadside base stations.

In order to achieve the above object, the technical solution of the present invention is achieved in that:

A vehicle-road coordination system using the vehicle-mounted T-Box, including a vehicle equipped with a vehicle-mounted T-Box and a roadside unit. The vehicle T-Box communicates with other vehicles and roadside units that are also equipped with a vehicle-mounted T-Box The edge base station builds a mobile ad hoc network to realize data communication.

The beneficial effect of the vehicle-road coordination system using the above-mentioned vehicle-mounted T-Box described in the present invention is the same as that of the above-mentioned vehicle-mounted T-Box based on DSRC and low-altitude satellite communication, and will not be repeated here.

Another object of the present invention is to propose a method for vehicle-road coordination using the vehicle-mounted T-Box to realize real-time interaction and sharing of dynamic information between vehicles, vehicles and people, and vehicles and roadside base stations.

In order to achieve the above object, the technical solution of the present invention is achieved in that:

A method for vehicle-road coordination using the vehicle-mounted T-Box above. The vehicle-mounted T-Box as the sender sends data or safety information with a frequency of 5.8GHz to surrounding vehicles or roadside units in the form of broadcast through the DSRC module , after service registration request, authentication, and channel access allocation, two-way data transmission is established. The vehicle-mounted T-Box as the receiver verifies the message received by the sender according to the data transmission protocol, and decodes the message after confirming that it is valid, and converts the message Send it to the cloud platform for processing, and the cloud platform will return the processed message to the vehicle T-Box, and display it through the human-computer interaction module, and the vehicle actuator will perform corresponding actions according to the output of the receiver.

Further, when the vehicle-mounted T-Box sends a message to the cloud platform for data exchange with the cloud platform, it is verified by the device authentication center, and the root key is used to encrypt the transmission authentication key AK between the vehicle-mounted T-Box and the cloud platform, and the device The authentication center generates random number seeds and random queries and sends them to the security chip of T-BOX; the security chip calculates the session key through the encryption algorithm VA11 according to RS and AK, and then calculates the response and derives the key through the encryption algorithm VA12 according to RAND1, T -BOX sends the calculated RES1 to the device authentication center; the device authentication center calculates the session key through the algorithm VA11 according to RS and AK, and then calculates the expected response and derives the key through the algorithm VA12 according to RAND1, and the cloud platform sends T-BOX The sent RES1 is compared with the calculated XRES1, if the values are equal, the operation result R1 is set as true and sent to T-BOX, the device authentication is successful.

The beneficial effect of the vehicle-road coordination system using the above-mentioned vehicle-mounted T-Box described in the present invention is the same as that of the above-mentioned vehicle-mounted T-Box based on DSRC and low-altitude satellite communication, and will not be repeated here.

Description of drawings

The drawings constituting a part of the present invention are used to provide a further understanding of the present invention, and the schematic embodiments and descriptions of the present invention are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the attached picture:

Fig. 1 is the system block diagram of the vehicle-mounted T-BOX described in the embodiment of the present invention;

Fig. 2 is a structural block diagram of the vehicle-mounted T-BOX data acquisition unit described in the embodiment of the present invention;

Fig. 3 is a structural block diagram of the vehicle-mounted T-BOX wireless communication unit described in the embodiment of the present invention;

Fig. 4 is the functional block diagram of the vehicle-mounted T-BOX described in the embodiment of the present invention

Fig. 5 is the functional structural diagram of the vehicle-mounted T-BOX described in the embodiment of the present invention;

6 is a schematic diagram of a vehicle-road coordination system based on a vehicle-mounted T-BOX according to an embodiment of the present invention;

FIG. 7 is a flow chart of a vehicle forward collision detection algorithm according to an embodiment of the present invention;

Fig. 8 is a schematic diagram of the safety authentication process of the data exchange device of the vehicle-mounted T-BOX described in the embodiment of the present invention;

Fig. 9 is a schematic diagram of text message verification of the vehicle-mounted T-BOX remote control described in the embodiment of the present invention.

Detailed ways

It should be noted that, in the case of no conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

In describing the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", " The orientations or positional relationships indicated by "vertical", "horizontal", "top", "bottom", "inner" and "outer" are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and Simplified descriptions, rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and thus should not be construed as limiting the invention. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and should not be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, a feature defined as "first", "second", etc. may expressly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention based on specific situations.

The present invention will be described in detail below with reference to the accompanying drawings and examples.

Fig. 1 is the block diagram of the hardware composition of vehicle-mounted T-BOX of the present invention, as shown in Figure 1, vehicle-mounted T-Box hardware of the present invention adopts dual processor architecture design, based on the Freescal i.MX6 single-chip microcomputer of Cortex A9 kernel as main processing The processor CPU chip runs at a frequency of 1.2GHz, and the Freescal MPC5604B acts as a slave processor MCU chip with a running frequency of 64MHz. The CPU and the MCU are interconnected through the SPI interface. It is mainly composed of two parts: data acquisition unit and wireless communication unit.

The data acquisition unit includes a slave processor (MPC5604), a data storage (FRAM) and a CAN communication module.

Described wireless communication module comprises main processor (Freescal i.MX6), DSRC communication module, 4G communication module, low-altitude satellite communication module, WiFi/BT module, GPS/Beidou positioning module, RTC real-time clock module, battery management unit (PMU ), storage module (EMMC and LPDDR), voice module, codec module, human-computer interaction module, security chip.

The data acquisition unit collects the instrument panel information of the vehicle, each ECU status information and fault information, etc. in real time through two CAN buses, and sends the collected information to the cloud platform for processing and analysis through the 4G communication module in the wireless communication unit. And send the results to mobile terminals, such as notebooks, mobile phones, Pads and other mobile devices. Different mobile devices are suitable for different people. The data storage (FRAM) stores the collected information when the wireless communication unit cannot receive data, and completes the data transmission when the wireless communication unit can work normally.

By adding a low-altitude satellite communication module to the wireless communication unit, the vehicles traveling on the ground can be directly connected to the satellites in the air, and reliable data transmission can be established, which can effectively avoid the impact on the communication signal quality due to the obstruction of buildings or terrain. Low-altitude satellites can provide faster transmission speeds than traditional satellite communications with an average transmission speed of 50-100Mbps, which can fully meet the real-time data transmission requirements of the Internet of Vehicles. In addition, by sending multiple low-altitude satellites, full coverage of low-altitude ground communication signals can be achieved, further ensuring the stability and reliability of low-altitude communication signals. In view of the fact that the current number of low-altitude satellites cannot achieve full signal coverage, the communication unit is realized by combining the 4G communication module and the low-altitude satellite communication module. Seamless switching to ensure the reliability of the network connection when the vehicle is driving. While the wireless communication unit transmits data to the cloud through the communication module, it can also directly send the data to the user's mobile phone through the WiFi/BT module. WiFi hotspot. The GPS/Beidou positioning module in the wireless communication unit transmits the location information of the vehicle to the cloud platform or the vehicle dispatching center in real time through the communication module.

The wireless communication unit can also receive data from the cloud platform or the user's mobile phone, and convert it into message data that can be recognized by the CAN bus, so as to realize the remote operation of the BCM and the vehicle, such as electronic fence, remote vehicle tracking, speeding reminder , Remotely switch door locks, turn on air conditioners, turn on lights, etc.

The DSRC module in the wireless communication unit is used to establish a wireless communication connection between the vehicle and the vehicle, and between the vehicle and the road. The vehicle-mounted T-Box transmits a frequency of 5.8GHz data or security information, after a series of service registration requests and authentication. After the channel access allocation, the two parties can establish two-way data transmission, and after the data interaction is completed, the link is terminated through the service logout. Through such a link, nearby vehicles can share their status information, location information, etc., thereby supporting a wide range of connected cars, collaborative intelligent transportation and autonomous driving applications, such as collision avoidance warning, blind spot detection, emergency vehicle information notification, collaboration Intelligent traffic lights, fleet vehicle coordination, intelligent transportation facilities, etc.

Fig. 2 is a structural block diagram of the vehicle-mounted T-BOX data acquisition unit of the present invention, including a slave processor (MPC5604), a data storage (FRAM) and a CAN communication module. These modules and their functions are described in detail below.

CAN communication module: CAN communication module adopts automotive-grade high-speed CAN transceiver, fully complies with ISO11898 standard low power consumption mode, can wake up through the bus, reserves two CAN interfaces, and the baud rate can be set to 250K and 500K. It is used to collect vehicle dashboard information, vehicle operating status information, fault information, etc. on the CAN bus in real time. Data is the basis for remote monitoring and control of vehicles.

Data storage (FRAM): Store the collected information when the wireless communication unit cannot receive data, and complete the data transmission when the wireless communication unit can work normally, and the stored data is marked with time. For example, when the car is just started, the slave processor (MPC5604) has completed data collection through the CAN bus, and the main processor of the wireless communication unit has a built-in operating system, which starts slowly and cannot receive the collected data, resulting in data loss and potential safety hazards . At this time, the data storage (FRAM) can store the collected information, and upload the data after the wireless communication unit is fully activated, so as to ensure the integrity and reliability of the data.

Fig. 3 is a structural block diagram of the vehicle-mounted T-BOX wireless communication unit of the present invention, including main processor (Freescali.MX6), 4G communication module, low-altitude satellite communication module, DSRC communication module, WiFi/BT module, GPS/Beidou positioning module, RTC Real-time clock module, battery management unit (PMU), storage module (EMMC and LPDDR), voice module, codec module, human-computer interaction module, security chip. These modules and their functions are described in detail below.

4G communication module: Huawei ME909s-821LTE communication module is adopted, which can support high-speed USB2.0 interface, which is convenient for data exchange with other modules of the terminal. Based on the 4G communication module, the vehicle can establish a wireless connection with the 4G communication base station, and then realize the data transmission between the vehicle and the cloud, OTA remote flashing, remote control of the vehicle, remote diagnosis and other functions, and truly realize the connection of vehicles in the driving environment to the network.

Low-altitude satellite communication module: adopt the latest low-altitude satellite communication module in China to realize the direct connection between vehicles on the ground and the satellites in the air, establish reliable data transmission, and effectively avoid the impact on the quality of communication signals due to the obstruction of buildings or terrain Low-altitude satellites can provide faster transmission speeds than traditional satellite communications with an average transmission speed of 50-100Mbps, which can fully meet the real-time data transmission requirements of the Internet of Vehicles. In addition, by sending multiple low-altitude satellites, full coverage of low-altitude ground communication signals can be achieved, further ensuring the stability and reliability of low-altitude communication signals. In view of the fact that the current number of low-altitude satellites cannot achieve full signal coverage, the communication unit is realized by combining the 4G communication module and the low-altitude satellite communication module. Seamless switching to ensure the reliability of the network connection when the vehicle is driving.

WiFi/BT module: It adopts the LBEE6U4ZQC embedded module that conforms to the network standard based on the universal serial interface, and has a built-in TCP/IP protocol stack, which can realize the data conversion between the user serial port and the wireless network (Wi-Fi) interface; Wireless standards such as IEEE802.1 1a/b/g/n/ac; WiFi hotspots can be provided in the car to improve the driving experience; the collected vehicle status information can also be directly sent to the user's mobile phone through WiFi or Bluetooth.

GPS/Beidou positioning module: The NEO-M8L automotive dead reckoning (ADR, Automotive Dead Reckoning) module launched by the Swiss company u-blox, this module integrates motion, direction and height sensors, and it has the ability to install the module without directionality restrictions, mileage Features such as table function and autonomous data recording can provide reliable and uninterrupted positioning functions in strict environments such as urban areas with many buildings, tunnels, and basement parking lots. In addition, the module can track all visible GNSS satellites, including GPS, GLONASS, Beidou and all SBAS systems, and can output positioning information at a speed of up to 20 times per second, providing remote monitoring and navigation for vehicles location information.

DSRC communication module: With the DSRC module jointly developed by Cohda and NXP as the core, the peripheral interface circuit is expanded to form a DSRC communication module, which can support the IEEE 802.11p protocol, and can exchange information at a high speed and reliably within a large distance, shortening the Response times', especially the transfer of information about potentially hazardous and life-critical situations, are significantly faster than conventional applications. In addition, to protect connected cars from hacking and data theft, the module also integrates NXP's integrated solutions for V2X security, including hardware security modules (HSM) and authentication acceleration.

RTC real-time clock module: provide real-time clock for vehicle T-BOX, and provide time stamp for transmitted data. And provide time synchronization function.

Battery Management Unit (PMU): The power management unit is a highly integrated power management solution for portable applications, which integrates several types of traditional discrete power management devices into a single package, which can achieve higher power conversion Efficiency and lower power consumption, and fewer component counts to fit into reduced board space. Meet the 9-36V input and provide the required power for T-BOX.

Storage module (EMMC): The EMMC chip of model MTFC8GLVEA is used, which has the characteristics of small size, small footprint, and high-speed transmission. Not only equipped with high-capacity NAND Flash, high-performance controller, but also powerful. And adopt JEDEC standard EMMC interface. The storage module based on EMMC can realize the following functions:

①Data backup: The data backup function can back up the data uploaded to the cloud platform so that it can be downloaded and viewed when needed.

②Parameter setting: Store some setting parameters of T-BOX, such as the marking information used to identify the vehicle terminal.

③ Flashing program storage: When remotely flashing programs on T-BOX, the flashing program can be stored in EMMC first, and then the program flashing of the system or each CAN node can be completed.

Voice module and encoding and decoding module: provide voice services for passengers or upload the service needs of passengers to the cloud through voice information encoding, and can also receive data from the cloud and decode it into voice information for users. And can provide e-call remote rescue service.

Fig. 4 is a functional block diagram of the vehicle-mounted T-BOX of the present invention, describing all the functions that the vehicle-mounted T-BOX of the present invention can realize. Fig. 5 is the functional structural diagram of the vehicle-mounted T-BOX of the present invention, as shown in Fig. 5, the vehicle collects the status information of the vehicle in real time through the vehicle-mounted T-BOX, information such as location information and the service needs of the passengers, and passes the communication module data Upload to the cloud platform. The vehicle-mounted T-BOX can also receive data from the cloud platform, and convert vehicle control data into message data recognizable by the CAN bus, thereby realizing remote control of the vehicle. The cloud platform analyzes and processes the received data, and can directly send the information that the user cares about to the user's mobile phone, providing users with more convenient, intelligent, and diversified services; the monitoring terminal of the vehicle manufacturing company can obtain data from the cloud platform to understand Vehicle status and fault information to provide users with more value-added services; the vehicle dispatch center can also obtain vehicle data from the cloud platform, thereby reasonably arranging traffic flow, effectively relieving traffic pressure, and providing more convenient and efficient travel routes for car owners .

Fig. 6 is a schematic diagram of a vehicle-road coordination system based on a vehicle-mounted T-BOX in the present invention. As shown in Fig. 6, the system consists of a vehicle equipped with a vehicle-mounted T-Box and a roadside unit (called a roadside base station (RSU)). The vehicle-mounted T-Box realizes mobile ad hoc organization with other vehicles and roadside base stations that are also equipped with the vehicle-mounted T-Box through a (short-range) wireless communication module dedicated to cooperative intelligent transportation and road safety and other potential optional communication methods Network (MANET). The mobile ad-hoc network built by the vehicle-mounted T-Box allows nodes to communicate in a fully distributed manner without the need for a centralized coordinating instance. If a wireless connection exists between the nodes, the on-board unit will communicate directly. If there is no direct connection, a dedicated routing protocol allows multi-hop network communication, so that data is forwarded from one vehicle T-Box to other vehicle T-Boxes until it reaches its destination. The main tasks of roadside base stations are to improve road safety by executing specific applications and to extend the coverage of ad hoc networks by sending, receiving or forwarding data in the ad hoc network domain.

Based on a dedicated short-distance wireless communication protocol, the vehicle-road coordination system built with the vehicle-mounted T-Box as the core provides a packet switching network similar to that between mobile nodes in a traditional wireless environment and provides unicast, multicast, arbitrary broadcast and broadcast communication types. However, traditional wireless communication is a typical sender-centered propagation, and the vehicle-road coordination system is receiver-centered for data propagation. In the receiver-centered propagation, the source node detects risks through its local sensors and gives Its neighbors distribute information. Neighbors merge this information with their local information state and distribute the merged information to their neighbors. The information space and distribution timing are controlled by the receiving node as the carrier. After receiving the information, the receiving node determines the relevance of the information to the neighboring nodes and decides whether to distribute the information. In addition, the vehicle-road coordination system built with the vehicle-mounted T-Box as the core applies a novel geographic location-based addressing scheme. Basically, two types of geographic addressing are defined: first, distinct node addresses (i.e., V2X communication network addresses) are related to the physical location of the nodes. The forwarding algorithm uses this location to transmit the packet to the destination node. Second, geolocation is used to define geographic areas based on geometric shapes (such as circles, rectangles, etc.). Geographic areas can be associated with nodes, address all nodes within the area, or address any node within the area.

According to the basic communication rules and addressing methods of the above-mentioned vehicle-road coordination system, the data packet forwarding algorithm between the vehicle T-Boxes is formulated, including geographic unicast, topological domain broadcast (TSB), geographic broadcast and geographic anycast. Geographic unicast is used for single-wire data transmission from a single node (source) to a single node (destination), through direct communication based on the address specified by DSRC communication (including node identifier, geographic location, time information) or through multiple The jump completes the forwarding. Topological intra-domain broadcasting is used for data transmission from a single node (source) to all nodes within the coverage of the vehicle ad hoc. Geobroadcasting is used for data dissemination from a single node to all nodes in a target area. In contrast to topological intra-domain broadcasts, geographic broadcast target area ranges are defined by geographic regions. Geographic areas are defined in turn by geometric shapes, such as circles and rectangles. Geographic anycast is the dissemination of data from a single node to any node in a geographic area. Compared with geographic broadcast, in geographic anycast, when a packet arrives at a node in the area, the packet will not be forwarded.

Combining the above-mentioned addressing mode and data packet forwarding algorithm of the vehicle-road coordination system, the specific implementation methods and working principles of the vehicle-road coordination use cases described in the accompanying drawings are pointed out. Based on the security requirements and information exchange types of these use cases, they are Assigned to 4 "applications". Therefore, these applications provide a general mechanism for use by any number of use cases. The requirements and general mechanisms for each application are described below.

(1) Vehicle-to-vehicle cooperation. This application supports the requirement that vehicles share information without a continuous communication link between each other. Vehicles send data to all nearby vehicles or vehicles in the area through broadcast or regional simulcast, respectively, to achieve Sharing of vehicle information. This application contains 3 application instances: sender, receiver and vehicle actuator. The sender and receiver are respectively played by the vehicle-mounted T-Box of the interactive vehicle, and the sender needs to obtain the local vehicle data required by the corresponding application case, including vehicle speed and acceleration and deceleration information, vehicle driving direction and deflection angle, vehicle status and fault information , Vehicle high-precision positioning and driving lane information, etc. These information are obtained by on-board sensors and other smart devices, and are transmitted to the on-board T-Box through the on-board Ethernet bus or conventional CAN bus; then the on-board T-Box as the sender sends the local vehicle The data is packaged into messages according to the J2735 dedicated short-distance data transmission protocol, and the messages are sent to nearby vehicles using a broadcast or regional multicast mechanism. The vehicle-mounted T-Box as the receiver verifies the message received from the sender according to the data transmission protocol, and decodes the message into remote vehicle data after confirming that it is valid, and then evaluates the content of the message according to the requirements of the specific use case. output to take appropriate action. The specific implementation of the application is illustrated with the use case of cooperative forward collision warning. Vehicles driving on the road use the mechanism of broadcast or regional multicast to send their own vehicle information according to the requirements. After receiving the information, nearby vehicles will execute the forward collision detection algorithm. Assess the threat of other vehicles to your own vehicle. The forward collision detection algorithm is shown in Figure 7. The algorithm takes the data sent by the sender and the locally collected vehicle data as input, compares the current lane information, vehicle speed, acceleration/deceleration information and high-precision positioning information of nearby vehicles and calculates The critical safety distance of the vehicle, the commonly used critical safety distance calculation formula is shown in formula (1).

(1)

In the formula, D _w is the forward collision warning distance; V _f , a _f , V _l , a _l are the speed and deceleration of the front vehicle and the rear (own) vehicle, respectively. If the algorithm detects that two vehicles in the same lane will have a potential forward collision with the current acceleration or deceleration, the on-board T-Box will send the result to the vehicle man-machine interface through the USB interface to give the driver a warning. In addition, use cases based on the application include cooperative adaptive cruise control, overtaking warning, etc.

(2) Vehicle-to-Vehicle Decentralized Environmental Notification, this application provides information about events and road features that are of interest to the driver in a specific area and time. This application contains 3 application instances: Monitor, Sender, Receiver. The monitor mainly includes the existing infrastructure on the road, such as traffic monitoring system, visibility sensor, wind sensor on the bridge, road information warning, etc. After collecting relevant data, the monitor sends the message to the nearby roadside through the Internet connection Unit (RSU), messages include distribution parameters (e.g. priority, validity), authentication data (e.g. signature), location and event and road information described using a standardized risk type scheme. The Roadside Unit (RSU) then plays the role of the sender, using a broadcast or regional multicast mechanism to send messages to surrounding vehicles or vehicles within a geographic area. The on-board T-Box of the vehicle acts as a receiver to decode the received message and confirm the validity of the message, save the valid message and discard the invalid message. Then the messages describing the same event or road information are clustered according to the standardized risk type scheme, the information of the cluster distribution is prioritized, and delivered to the vehicle human-machine interface with the highest priority. In this app, messages contain information about events and traffic conditions. Note that road conditions can be static or dynamic, (eg freezing rain - static, traffic jam - dynamic). Each message contains information about a single event or traffic condition, for independent dissemination of information. Each message consists of the following 3 parts:

Parameters for message management: This information is used to satisfy individual processing of messages. It contains: a random and unique message ID. Since the message ID is generated independently by the vehicle, complete uniqueness cannot be guaranteed unless it includes location and time information, which would result in a very long ID. So the system must avoid ID duplication. Timestamp of the message, priority, reliability of the message set by the initiator, limit of the target area, expiration time.

Location information: This information is required in order to cluster information and to help the driver identify relevant messages. Therefore, the location information of different messages must be matched and the own driving path must be matched with the message. In order to achieve matching, not only the event location is added to the message but also the location tracking descriptor is added. This tracking information must be coordinated with a dedicated digital map.

Event and traffic information: Event and traffic information is encoded using a standardized, extensible scheme.

The implementation of this application is illustrated below with a hazard warning use case where a monitor monitors events like traffic accidents or dangerous situations. In order to avoid information loss, the detector will send the dangerous event message to the roadside unit in the accident transmission area in time, and the roadside unit will broadcast the traffic accident danger warning message in the accident area and within a specific time. Vehicles in the area receive the broadcast message through the on-board T-Box and complete the decoding of the message and the clustering of the same event, and then pass the danger warning event to the vehicle man-machine interface through USB and hand it over to the driver (for example, auditory, visual and tactile) . In addition, the use cases based on this application include early warning of traffic jams, vehicle-to-vehicle notifications in dangerous areas, safety service points, blind spot warnings, etc.

(3) Infrastructure-vehicle (one-way) communication, this application supports communication from the roadside base station (RSU) to the vehicle when there is no continuous communication link between the vehicle and the roadside base station (RSU). The application can neither establish a two-way communication link nor receive and forward hazard warnings. These will be achieved through vehicle-to-vehicle distributed environmental notifications. This application contains 2 application examples: Roadside Unit (RSU) and Vehicle T-Box. The roadside unit (RSU) as the sender encapsulates the data to be broadcast into a short message according to the DSRC data transmission protocol, and then uses the broadcast mechanism to send the message to the surrounding vehicles. The on-board T-Box acts as a receiver to verify the received message and decode the message into remote RSU data, then evaluate the content of the message according to the use case requirements. And the evaluation results are transmitted to the vehicle human-machine interface. The speed limit broadcasting use case is used to illustrate the implementation of the application. The dynamic speed limit sign displays different restrictions according to the time of the day or special circumstances such as traffic jams. RSUs in this area will periodically broadcast messages containing speed limits. Furthermore, the message will contain additional information about the speed limit such as its geographic or directional limit. Vehicles in the area complete the decoding of the message after receiving the broadcast message through the on-board T-Box, and compare some geographical or directional restrictions in the message with the local data of the vehicle to determine whether the local vehicle applies the speed limit. If the vehicle speed collected by T-Box exceeds the current speed limit, T-Box will send overspeed information to the vehicle HMI via USB to send a warning to the driver. In addition, use cases implemented based on the app include consultation on the best speed for green lights, I2V notifications in dangerous areas, and more.

(4) Vehicle-to-vehicle unicast exchange, this application enables a communication link between two vehicles for exchanging information. The application consists of 4 distinct phases: discovery, connection, maintenance and shutdown. The discovery phase is when a vehicle decides to connect to other vehicles. In the subsequent connection phase the vehicle initiates a request to the other vehicle to open a connection. The other vehicle must decide whether to allow the connection. The maintenance phase is when the two vehicles are exchanging data while keeping the connection open. The close phase is when one of the two vehicles decides to stop exchanging data and closes the connection. The initiator will send a connection request to the target vehicle, and once the connection is established, the initiator must implement the duplex or two-way communication protocol required to realize the use case. This includes packaging vehicle information into messages and sending messages at the right time, the originator may close the connection at any time. The Responder shall respond to all Connection Requests, accepting or rejecting them. When a connection is established with an Initiator, the Responder shall implement the duplex or bi-directional communication protocol required to implement the use case. This includes packaging vehicle information into messages and sending messages at the right time. The responder shall request information from and send information to the vehicle system depending on the use case, and the responder may close the connection at any time. This application is generally used to establish instant communication between vehicles.

Fig. 8 is a schematic diagram of the authentication process of the data exchange equipment of the vehicle-mounted T-BOX of the present invention. When the vehicle-mounted T-BOX and the cloud platform carry out data exchange, it must be verified by the equipment certification center, and the root key is used to encrypt the data between the vehicle-mounted T-BOX and the platform. The authentication key AK is transmitted. The device authentication center generates a random number seed (RS) and a random query (RAND1) and sends them to the security chip of T-BOX; the security chip calculates the session key (KS) through the encryption algorithm VA11 according to RS and AK, and then uses the encryption algorithm according to RAND1 VA12 calculates the response (RES1) and derived key (DCK1), and T-BOX sends the calculated RES1 to the device authentication center; the device authentication center calculates the session key (KS) through algorithm VA11 according to RS and AK, and then according to RAND1 calculates the expected response (XRES1) and derived key (DCK1) through the algorithm VA12. The platform compares the RES1 sent by T-BOX with the calculated XRES1, and if the values are equal, it sets the operation result R1 as true and sends it to T-BOX, indicating that the device authentication is successful.

Figure 9 is a schematic diagram of SMS verification for remote control of the vehicle-mounted T-BOX according to the present invention. When the user performs high-risk applications such as remote unlocking or control through the vehicle-mounted T-Box, it is necessary to complete the two-factor authentication of the person and the service center. The user sends a service request to the cloud platform service center through the remote control service in the mobile APP, and the service center sends a randomly generated SMS verification code by querying the mobile phone number reserved by the user, and the user enters the received verification code to complete the verification.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (1)

1. A vehicle-mounted T-Box based on DSRC and low-altitude satellite communication, is characterized in that: comprise interconnected data acquisition unit and wireless communication unit, described data acquisition unit comprises slave processor, and is connected with described slave processor data storage, CAN communication module, the wireless communication unit includes a main processor, and a DSRC communication module connected to the main processor, a 4G communication module, a low-altitude satellite communication module, a WiFi/BT module, and a GPS/Beidou positioning module , an RTC real-time clock module, a battery management unit, a storage module, a voice module, a codec module, a human-computer interaction module and a security chip, and the main processor and the slave processor are connected through an SPI interface; The forwarding algorithm of data packet between described vehicle-mounted T-Box is: Including geographic unicast, topological domain broadcast, geographic broadcast and geographic anycast; The geographical unicast is used for single-line data transmission from a source to a destination, through direct communication based on the address specified by the DSRC communication or forwarding through multiple hops, and the broadcast within the topology domain is used for transmission from a source to all vehicles in the vehicle itself. Organize the data transmission of nodes within the coverage area; The geographic broadcast is used for data propagation from a single node to all nodes in the target area, the target area range of the geographic broadcast is defined by a geographic area, and the geographic area is sequentially defined by a geometric shape; The geographical anycast is data transmission from a single node to any node in the geographical area, and in the geographical anycast, when the data packet arrives at the node in the area, the data packet will not be forwarded; The data collection unit collects vehicle instrument panel information, each ECU status information and fault information through the CAN bus on both sides, and sends the collected information to the cloud platform through the 4G communication module in the wireless communication unit for processing, and through the WiFi /BT module sends the result to the mobile terminal; The GPS/Beidou positioning module in the wireless communication unit transmits the location information of the vehicle to the cloud platform or the vehicle dispatching center in real time through the 4G communication module; The wireless communication unit receives the data from the cloud platform or the user's mobile phone, and converts it into message data that can be recognized by the CAN bus, so as to realize the remote operation of the vehicle; The vehicle-road coordination system using the above-mentioned vehicle-mounted T-Box: including the vehicle equipped with the vehicle-mounted T-Box and the roadside unit. The vehicle T-Box communicates with other vehicles and roadside base stations that are also equipped with the vehicle-mounted T-Box through wireless communication. Build a mobile ad hoc network to realize data communication; The method of applying the above-mentioned vehicle-mounted T-Box for vehicle-road coordination: as the sender, the vehicle-mounted T-Box transmits data or safety information with a frequency of 5.8 GHz to surrounding vehicles or roadside units in the form of broadcast through the DSRC module. After service registration request, authentication, and channel access allocation, two-way data transmission is established. The vehicle-mounted T-Box as the receiver verifies the message received by the sender according to the data transmission protocol. After confirming that it is valid, the message is decoded and sent to The cloud platform performs processing, and the cloud platform returns the processed message to the vehicle T-Box, and displays it through the human-computer interaction module, and the vehicle actuator executes corresponding actions according to the output of the receiver; When the vehicle-mounted T-Box sends a message to the cloud platform for data exchange with the cloud platform, it is verified by the equipment certification center, and the transmission authentication key AK between the vehicle-mounted T-Box and the cloud platform is encrypted with the root key, and the equipment certification center generates The random number seed and random query are sent to the security chip of T-BOX; the security chip calculates the session key through the encryption algorithm VA11 according to RS and AK, and then calculates the response and derives the key through the encryption algorithm VA12 according to RAND1, and T-BOX will The calculated RES1 is sent to the device authentication center; the device authentication center calculates the session key through the algorithm VA11 according to RS and AK, and then calculates the expected response and derives the key through the algorithm VA12 according to RAND1, and the cloud platform sends the T-BOX RES1 is compared with the calculated XRES1, if the value is the same, the operation result R1 is set as true and sent to T-BOX, the device authentication is successful; The above vehicle-mounted T-Box system for vehicle-road coordination has four application programs under different conditions. The requirements and general mechanisms of the application programs are as follows: Vehicle-to-vehicle cooperation, this application supports the requirement that vehicles share information without a continuous communication link between each other. Vehicles send data to all nearby vehicles or vehicles in the area through broadcast or regional simulcast, respectively, to achieve - vehicle information sharing; this application contains 3 application instances: sender, receiver, and vehicle actuator; where the sender and receiver are played by the on-board T-Box of the interactive vehicle, and the sender needs to obtain the local vehicle required by the corresponding application Data, including vehicle speed and acceleration and deceleration information, vehicle driving direction and deflection angle, vehicle status and fault information, vehicle high-precision positioning and driving lane information, these information are obtained by on-board sensors and other smart devices, through the on-board Ethernet bus or conventional The CAN bus is transmitted to the on-board T-Box; then the on-board T-Box as the sender packs the local vehicle data into a message according to the J2735 dedicated short-distance data transmission protocol, and sends the message to nearby vehicles using a broadcast or regional multicast mechanism ;As the receiver, the vehicle-mounted T-Box verifies the message received from the sender according to the data transmission protocol, and decodes the message into remote vehicle data after confirming that it is valid, and then evaluates the content of the message according to the requirements of the specific use case. Take appropriate action on the output of the operator; use the example of cooperative forward collision warning to illustrate the specific implementation of the application program. Vehicles driving on the road use the mechanism of broadcast or regional multicast to send their own vehicle information according to the requirements. After receiving the information, nearby vehicles The forward collision detection algorithm will be executed to evaluate the threat of other vehicles to its own vehicle; the forward collision detection algorithm is shown in Figure 7, the algorithm uses the data sent by the sender and the locally collected vehicle data as input, and compares the current lanes of nearby vehicles Information, vehicle speed and acceleration/deceleration information and high-precision positioning information and calculate the critical safety distance of the vehicle. The commonly used critical safety distance calculation formula is as follows:

In the formula, D _w is the forward collision warning distance; V _f , a _f , V _l , a _l are the speed and deceleration of the front vehicle and the rear vehicle respectively, and T _w is the braking reaction time; if the algorithm detects Two vehicles will have a potential forward collision with the current acceleration or deceleration, and the on-board T-Box will send the result to the vehicle HMI through the USB interface to give the driver a warning; in addition, the use cases based on this application are also Including cooperative adaptive cruise control, overtaking warning; Vehicle-to-vehicle decentralized environmental notification, this application provides information about events and road features that are of interest to the driver in a specific area and time; this application contains 3 application instances: monitor, sender , receivers; monitors mainly include existing infrastructure on the road, such as traffic monitoring systems, visibility sensors, wind sensors on bridges, and road information warnings. After collecting relevant data, monitors send messages to nearby via Internet connection Roadside Unit (RSU), the message includes distribution parameters (e.g. priority, validity), authentication data (e.g. signature), location and event and road information described using a standardized risk type scheme; then the Roadside Unit (RSU) Acting as a sender, use broadcast or regional multicast mechanism to send messages to surrounding vehicles or vehicles in a geographical area; the vehicle's on-board T-Box acts as a receiver to decode the received message and confirm the validity of the message , save valid messages and discard invalid messages; then cluster messages describing the same event or road information according to the standardized risk type scheme, give priority to the cluster distribution information, and pass it to the vehicle human-machine interface with the highest priority; the application In the program, messages contain information about events and road conditions; note that road conditions can be static or dynamic, (such as freezing rain-static, traffic jam-dynamic); each message contains information about a single event or road condition, for independent release information; each message consists of the following three parts: Parameters for message management: This information is used to satisfy the independent processing of messages; it contains: a random and unique message ID; since the vehicle independently generates the message ID, complete uniqueness cannot be guaranteed unless it contains location and time information , which will lead to a very long ID; therefore the system must avoid ID duplication; the timestamp of the message, the priority, the reliability of the message set by the initiator, the limit of the target area, and the expiration time; Location information: This information is necessary to cluster information and help drivers identify related messages; therefore, the location information of different messages must be matched and their own driving path must match the message; in order to achieve matching, not only the event location must be added To the message and add a location tracking descriptor; this tracking information must cooperate with a dedicated digital map; Event and traffic information: Event and traffic information is encoded using a standardized, extensible scheme; The specific implementation of the application is described below with a danger warning use case. The monitor monitors events such as traffic accidents or dangerous situations; in order to avoid information loss, the detector will send the danger event message to the roadside unit in the accident sending area in time , the roadside unit broadcasts traffic accident danger warning messages in the accident area and within a specific time; the vehicles in the area receive the broadcasted messages through the on-board T-Box and complete the message decoding and clustering of the same event, and then send the danger warning events through the USB Passed to the vehicle human-machine interface and delivered to the driver (for example, auditory, visual and tactile); in addition, use cases based on this application include early warning of traffic jams, vehicle-to-vehicle notifications in dangerous areas, safety service points, and blind spot warnings; Infrastructure-to-vehicle (one-way) communication, this application supports communication from the RSU to the vehicle when there is no continuous communication link between the vehicle and the RSU; the application cannot establish a two-way The communication link also cannot receive and forward hazard warnings; these will be realized through vehicle-to-vehicle distributed environment notification; this application contains 2 application examples: roadside unit (RSU) and vehicle T-Box; where roadside unit (RSU ) as the sender encapsulates the data that needs to be broadcast into a short message according to the DSRC data transmission protocol, and then uses the broadcast mechanism to send the message to the surrounding vehicles; the vehicle T-Box acts as the receiver to verify the received message and decode the message into remote RSU data , and then evaluate the content of the message according to the use case requirements; and pass the evaluation results to the vehicle human-machine interface; use the speed limit broadcasting use case to illustrate the implementation of the application. The RSU in the area will periodically broadcast a message containing the speed limit; in addition, the message will contain additional information about the speed limit such as its geographic or directional restrictions; vehicles in the area receive the broadcast message through the on-board T-Box After decoding the message, compare some geographical or directional restrictions in the message with the vehicle's local data to determine whether the local vehicle applies a speed limit; if the vehicle speed collected by the T-Box exceeds the current speed limit, the T-Box will pass the USB Send overspeed information to the vehicle man-machine interface to send a warning to the driver; in addition, use cases based on this application include green light optimal speed consultation, I2V notification in dangerous areas; Vehicle-to-vehicle unicast exchange, an application that enables a communication link between two vehicles for exchanging information; this application consists of 4 distinct phases: discovery, connection, maintenance, and shutdown; the discovery phase refers to a The phase in which the vehicle decides to connect to the other vehicle; in the subsequent connection phase the vehicle initiates a request to the other vehicle to open a connection; the other vehicle must decide whether to allow the connection; the maintenance phase is when the two vehicles are exchanging data while keeping the connection open ;The close phase is when one of the two vehicles decides to stop exchanging data and closes the connection; the initiator will send a connection request to the target vehicle, once the connection is established, the initiator must perform the duplex or two-way communication required to realize the use case protocol; this includes packaging vehicle information into messages and sending messages at the right time, the initiator closes the connection at any time; the responder should respond to all connection requests, accept or reject; when a connection with an initiator is established, the responder The duplex or two-way communication protocol required to realize the use case should be implemented; this includes packaging vehicle information into messages and sending messages at the appropriate time; the responder should request information from the vehicle system and send information to the vehicle system, depending on the use case, The responder closes the connection at any time; the application is generally used to establish instant communication between vehicles.

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