CN114885307A - In-vehicle wireless communication system - Google Patents

Abstract

The invention discloses an in-vehicle wireless communication system, which comprises a vehicle body area controller, a vehicle body area controller and a vehicle body area controller, wherein the vehicle body area controller is connected with other controllers through wireless communication; after the vehicle is electrified and operated, the vehicle body area controller and other controllers confirm to establish communication in a sequential polling mode; when a substantial communication demand exists, the body area controller sends the same control demand to the target controller at different frequencies for multiple times, and each controller confirms whether the controller needs to execute the control demand and whether the control demand is a safety request or not through judging the message; if the system needs to be executed by the target controller and the request is safe, the target controller continuously sends the execution state of the current instruction for multiple times at different frequencies in the execution process and feeds the execution state back to the body domain controller, and the body domain controller judges and memorizes the current working state of the system after receiving the information and provides a basis for the next execution. The system breaks the constraint of wire harness design, deployment and maintenance on innovative vehicle-mounted application, reduces cost, improves efficiency and further catalyzes novel vehicle-mounted application and market.

Description

In-vehicle wireless communication system

Technical Field

The invention belongs to the field of vehicle communication, and particularly relates to an in-vehicle wireless communication system.

Background

Vehicle communication can be simply divided into in-vehicle communication (communication between controllers, communication between controllers and actuators, communication between controllers and sensors, etc.) and vehicle-to-outside communication (4G, 5G, V2X interconnection, etc.).

In the vehicle, the electronic control technology of the vehicle is developed for decades, the technical scheme is started from hard-wire communication, and communication forms such as K-line communication, CAN communication, LIN communication, Flex Ray, CAN FD, Ethernet, optical fiber and the like gradually appear. At present, hard wires, CAN communication, LIN communication, Ethernet and the like are mainly used in vehicles, and the communication forms are respectively existed in certain parts of the whole vehicle communication structure because of respective advantages and disadvantages.

With the rise and development of new energy vehicles and intelligent networked vehicles, the number of controllers in the vehicles is more and more, the requirements for in-vehicle communication are met by the requirements for larger capacity, higher speed and smaller time delay, and communication structures of whole vehicles are optimized by whole vehicle factories so as to meet new communication requirements with simpler structures and lower cost.

Most of the whole automobile factories launch a new generation of electronic and electrical appliance architecture, specifically, the distributed control is changed into the pre-control type, and part of CAN communication is changed into Ethernet communication. According to the technical scheme, function distribution of whole vehicle control is greatly optimized to a certain extent, communication data volume is reduced to a certain extent, but hard-wire communication is still adopted for vehicle body type and comfort type control with low real-time requirement and low reliability requirement, and severe problems of whole vehicle wiring harness design optimization, layout optimization and cost optimization are still faced.

Disclosure of Invention

The invention aims to provide an in-vehicle wireless communication system, which greatly reduces the number of wire harnesses through a wireless communication technology and fundamentally solves the problems of design optimization, arrangement optimization and cost optimization of the wire harness of a whole vehicle.

The invention provides an in-vehicle wireless communication system, which comprises a vehicle body area controller, wherein the vehicle body area controller is connected with other controllers through wireless communication, and the other controllers are part or all of an atmosphere lamp, a tire pressure sensor, a door module, a skylight sunshade curtain module, an air conditioner controller, an electric seat controller, a vehicle lamp controller, a wiper controller and an in-vehicle fragrance controller; each controller has its own ID;

after the vehicle is electrified and operated, the vehicle body area controller and other controllers confirm to establish communication in a sequential polling mode; when a substantial communication demand exists, the body area controller sends the same control demand to the target controller at different frequencies for multiple times, and each controller confirms whether the controller needs to execute and is a safe request or not after judging the sending ID, the receiving ID, the instruction code, the safety code and the check code in the message; if the system needs to be executed by the target controller and the request is safe, the target controller continuously sends the execution state of the current instruction for multiple times at different frequencies in the execution process and feeds the execution state back to the body domain controller, and the body domain controller judges and memorizes the current working state of the system after receiving the information and provides a basis for the next execution;

the sending signal of the body area controller comprises a frame header, a vehicle ID, a sending ID, a receiving ID, an instruction code, a safety code, a frame tail and a check code; the instruction code comprises instruction information and reserved bits;

the sending signals of other controllers comprise a frame head, a vehicle ID, a sending ID, a receiving ID, an execution code, a safety code, a frame tail and a check code; the execution code comprises execution information, signal receiving, signal error requesting to resend, instruction executing, instruction execution finishing, system fault unable execution and reserved bits.

Further, the vehicle body domain controller sends the same control requirement to the target controller at the frequencies of 2.42GHz, 2.44GHz and 2.46GHz for three times, and meanwhile, the target controller continuously sends the execution state of the current instruction at the frequencies of 2.42GHz, 2.44GHz and 2.46GHz for three times in the execution process and feeds the execution state back to the vehicle body domain controller.

Further, the vehicle ID is obtained by converting the 17-digit vehicle VIN code.

Further, the command information needs to build a corresponding table, the command information corresponding table is unique between a pair of transceiver controllers, and one piece of command information is only related to one or one group of execution actions.

Further, the security code is encrypted by adopting a deformed fence, and the encryption process is as follows:

firstly, a body domain controller generates a true random number;

secondly, the body area controller carries out fence encryption on the true random number;

combining the true random number with the fence encryption result;

fourthly, the combined result is encrypted again by the fence;

and fifthly, sending the final result to the receiving controller as a safety code.

The application layer specification based on the wireless communication in the vehicle is as follows: the system comprises a communication specification combination of a vehicle body area controller and other controllers, and specification setting and combination of vehicle ID, sending ID, receiving ID, instruction code, execution code and safety code.

The interval polling mechanism applied to the invention ensures that each controller connected with the vehicle body area controller through wireless communication is in a working state.

The vehicle body area controller receives and judges the information sent back by other controllers, and judges whether illegal information invades. And then a safety alarm is carried out.

Compared with the prior art, the invention has the following advantages and beneficial effects:

the system comprehensively replaces the existing wired connection with low requirement on communication safety and low requirement on time delay by utilizing the in-vehicle wireless communication application layer specification and the topological structure, breaks the constraint of wire harness design, deployment and maintenance on innovative vehicle-mounted application, helps a host factory reduce cost and improve efficiency, and further catalyzes novel vehicle-mounted application and market.

Drawings

FIG. 1 is a topological block diagram of an in-vehicle wireless communication system of the present invention;

fig. 2 is a schematic diagram of an in-vehicle wireless communication system according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

The invention adopts a wireless technical scheme to replace part of wired communication connection in the existing vehicle, breaks through the constraint of wiring harness design, deployment and maintenance on innovative vehicle-mounted application, helps a host factory to reduce cost and improve efficiency, and further catalyzes novel vehicle-mounted application and market. The technology is mainly oriented to the communication between the small execution unit of the vehicle body and the controller in the communication of the whole vehicle, and compared with the communication between large controllers, the communication requirement is relatively low in real-time requirement (short time delay is allowed), the communication data volume is relatively small, the communication cost is sensitive, and the requirement on the optimization of the space in the vehicle is strong.

The basic communication topological structure of the invention is shown in figure 1, a vehicle body domain controller is connected with other controllers through wireless communication, 2.4GHz general communication wireless frequency band is adopted, and an ID sequence is written into each controller when a vehicle is off-line:

other controllers include atmosphere lamps, tire pressure sensors, door modules, sunroof shade modules, air conditioning controllers, power seat controllers, vehicle light controllers, wiper controllers, in-vehicle fragrance control, and the like.

Wireless communication application layer specification:

after the vehicle is electrified and operated, the vehicle body domain controller and other controller modules confirm to establish communication in a sequential polling mode, when a substantial communication demand exists, the vehicle body domain controller sends the same control demand to a certain control module in three times at different frequencies of 2.42GHz, 2.44GHz and 2.46GHz, each control module confirms whether the current command needs to be executed or not after judging ID sending, ID receiving, command codes, safety codes and check codes in a message, and whether the command is a safe request or not, the execution state of the current command is continuously sent in three times at different frequencies of 2.42GHz, 2.44GHz and 2.46GHz in the execution process after the confirmation is finished, the current working state of the system is fed back to the execution state of the vehicle body domain controller, and the vehicle body controller judges and memorizes the current working state of the system after receiving the information and provides a basis for the next execution.

The transmission signal specifications of the body area controller are shown in table 1, and the transmission signal specifications of the other controllers are shown in table 2.

TABLE 1 Transmission Signal Specification for body area controllers

Frame header

Vehicle ID

Sending ID

Receiving ID

Instruction code

Security code

Frame end

Check code

8 bit

136 bit

8 bit

8 bit

16 bit

16 bit

8 bit

8 bit

TABLE 2 Transmission Signal Specifications for other controllers

Frame header

Vehicle ID

Sending ID

Receiving ID

Execution code

Security code

Frame end

Check code

8 bit

136 bit

8 bit

8 bit

16 bit

16 bit

8 bit

8 bit

The part of the transmitted signal is expanded as follows:

1) vehicle ID: 136 bits from the 17-bit VIN, and this information is used to determine the signal source that is sent by the controller of the vehicle, thereby avoiding the signals sent by the controllers of other vehicles to some extent.

2) Sending ID: controller ID to send this signal

3) Receiving an ID: controller ID required to receive this signal

4) Instruction code: containing command information and reserved bits, as shown in table 3, the command information needs to build a corresponding table, the command information corresponding table is unique between a pair of transceiver controllers, and one piece of command information is only related to one or one group of execution actions.

TABLE 3 instruction code

5) Executing codes: as shown in table 4, the execution code mainly includes command information received by the controller, signal reception, signal error, request for resending, command being executed, completion of command execution, subsystem failure unable to be executed, and reserved bits. The reserved bits refer to data bits reserved in the whole execution code and not used for explicit purpose, and are used for future function extension, such as wireless wakeup and the like.

TABLE 4 execution code

6) A security code (the security code is for the body area controller to identify the legality of other modules communicating with the body area controller, since wireless signals can be sent and received by anyone, but whether other modules communicating with the body area controller are legal devices or not is judged through a series of encryption and decryption processes): adopting deformed fence encryption, wherein the encryption process is as follows:

firstly, a body domain controller generates a true random number: 1011;

secondly, the body domain controller performs fence encryption on the true random number to obtain: 1101;

combining the true random number and the fence encryption result into 8-bit number: 10111101;

fourthly, the result is encrypted again by a fence: 11011011, respectively;

and fifthly, sending the result to the receiving controller as a security code.

Specifically, as shown in fig. 2, the vehicle communication topology based on wireless communication is as follows: the vehicle body area controller is connected with the atmosphere lamp, the tire pressure sensor, the door module, the skylight sunshade curtain module, the air conditioner controller, the electric seat controller, the vehicle lamp controller, the wiper controller, the interior fragrance control and the like in a wireless mode. Control-class applications are such as:

atmosphere lamp: automobile body territory controller and a plurality of atmosphere lamp controller wireless connection can ensure 20us certainty time delay, enables atmosphere lamp modes such as monochromatic, polychrome, rhythm, provides good atmosphere experience in the car for the user.

Monitoring the tire pressure: the transmission of the data between the vehicle body area controller and the tire pressure sensor has the characteristic of resisting complex electromagnetic interference, can provide reliable and stable tire pressure data for users, and guarantees the driving safety.

And (3) door module control: the vehicle body area controller is in wireless connection with the communication of the door module, wireless control of functions such as rearview mirror position, door lock and vehicle window is achieved, vehicle door wiring harnesses are greatly reduced, and theoretically, each door module can work only by providing a hard-wire power supply signal.

Other similarities apply to the control scenario: body area controllers and sunroof modules, sunroof shade modules, air conditioning controllers, power seat controls, vehicle light controls, wiper controls, fragrance controls within the vehicle, and the like.

In summary, the invention provides an in-vehicle wireless communication application layer specification and a topological structure, aiming at vehicle body control with low requirement on in-vehicle communication real-time performance, aiming at the communication requirements, the in-vehicle wireless communication application layer specification is designed, and the solutions of partial communication interference prevention, external wireless attack prevention, data transmission effectiveness guarantee by multi-band transmission and connection effectiveness confirmation by polling are provided from wireless communication while meeting the communication real-time performance requirements, communication data quantity requirements, sensitive requirements on communication cost and requirements on in-vehicle space optimization.

It will be understood by those skilled in the art that the foregoing is only an exemplary embodiment of the present invention, and is not intended to limit the invention to the particular forms disclosed, since various modifications, substitutions and improvements within the spirit and scope of the invention are possible and within the scope of the appended claims.

Claims (5)

1. The system is characterized by comprising a vehicle body area controller, wherein the vehicle body area controller is connected with other controllers through wireless communication, and the other controllers are part or all of an atmosphere lamp, a tire pressure sensor, a door module, a skylight sunshade curtain module, an air conditioner controller, an electric seat controller, a vehicle lamp controller, a wiper controller and a vehicle interior atmosphere controller; each controller has its own ID;

after the vehicle is electrified and operated, the vehicle body area controller and other controllers confirm to establish communication in a sequential polling mode; when a substantial communication demand exists, the body area controller sends the same control demand to the target controller at different frequencies for multiple times, and each controller confirms whether the controller needs to execute and is a safe request or not after judging the sending ID, the receiving ID, the instruction code, the safety code and the check code in the message; if the system needs to be executed by the target controller and the request is safe, the target controller continuously sends the execution state of the current instruction for multiple times at different frequencies in the execution process and feeds the execution state back to the body domain controller, and the body domain controller judges and memorizes the current working state of the system after receiving the information and provides a basis for the next execution;

the sending signal of the vehicle body area controller comprises a frame header, a vehicle ID, a sending ID, a receiving ID, an instruction code, a safety code, a frame tail and a check code; the instruction code comprises instruction information and reserved bits;

the sending signals of other controllers comprise a frame head, a vehicle ID, a sending ID, a receiving ID, an execution code, a safety code, a frame tail and a check code; the execution code comprises execution information, signal receiving, signal error requesting to resend, instruction executing, instruction execution finishing, system fault unable execution and reserved bits.

2. The in-vehicle wireless communication system according to claim 1, wherein the body area controller transmits the same control requirement to the target controller at the frequencies of 2.42GHz, 2.44GHz and 2.46GHz in three times, and the target controller transmits the execution state of the current command to the body area controller at the frequencies of 2.42GHz, 2.44GHz and 2.46GHz in three times continuously during the execution process and feeds the execution state back to the body area controller.

3. The in-vehicle wireless communication system according to claim 1, wherein the vehicle ID is obtained by 17-digit vehicle VIN code conversion.

4. The in-vehicle wireless communication system according to claim 1, wherein the command message is required to construct a correspondence table, the command message correspondence table is unique between a pair of transceiver controllers, and one command message is associated with only one or a set of execution actions.

5. The in-vehicle wireless communication system according to claim 1, wherein the security code is encrypted using a modified barrier, the encryption process comprising:

firstly, a body domain controller generates a true random number;

secondly, the body area controller carries out fence encryption on the true random number;

combining the true random number with the fence encryption result;

fourthly, the combined result is encrypted again by the fence;

and fifthly, sending the final result to the receiving controller as a safety code.

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