CN114827968A

CN114827968A - Big data transmission method of BLE intelligent key CANFD

Info

Publication number: CN114827968A
Application number: CN202210333104.9A
Authority: CN
Inventors: 覃家勇; 谭文
Original assignee: Yuanfeng Technology Co Ltd
Current assignee: Yuanfeng Technology Co Ltd
Priority date: 2022-03-31
Filing date: 2022-03-31
Publication date: 2022-07-29
Anticipated expiration: 2042-03-31
Also published as: CN114827968B

Abstract

The invention discloses a big data transmission method of a BLE intelligent key CANFD, belonging to the field of wireless door locks; an ZCU controller is arranged between a BLE intelligent key system and a vehicle body BCM and serves as an intermediate node of a cipher text big data bidirectional transmission function of BLE safety certification; ZCU the controller includes a CANFD unpacking/packing component and a ZCU security component; when a big data ciphertext packet which exceeds 64 bytes is transmitted through a CANFD bus, the big data ciphertext packet can be unpacked into a plurality of frames of single-frame data which are smaller than 64 bytes for transmission, and the single-frame data ciphertext packet is received and then is subjected to packet recovery. The advantages are that: unpacking/packing data in a CANFD channel to realize single-frame bidirectional transmission of big data on a CANFD bus; in the unpacking/packaging process, the standard UDS specification is met; the protocol protection of E2E is realized on the protocol, and a CRC (cyclic redundancy check) mechanism is added to ensure the stable and fast transmission of data.

Description

Big data transmission method of BLE intelligent key CANFD

Technical Field

The invention relates to the field of wireless door locks, in particular to a key positioning system based on Bluetooth communication.

Background

The existing Bluetooth digital key is positioned by three-point positioning or fingerprint positioning by means of the RSSI (received signal strength indicator). A mature BLE intelligent key (Bluetooth intelligent key, wherein BLE is English abbreviation of Bluetooth) is that a BLE main node and a BLE slave node are connected into a vehicle body through a Bluetooth communication technology, and the BLE intelligent key is in control connection with a vehicle body BCM through the BLE main node. The BLE slave node monitors and obtains RSSI information to realize positioning, and the main functions of the BLE intelligent key are independently completed on the master node. The BLE intelligent key system comprises a movable digital key module, a Bluetooth master module and a plurality of Bluetooth slave modules, wherein the Bluetooth master module and the Bluetooth slave modules are arranged on a vehicle; the Bluetooth slave modules are distributed at different positions as Bluetooth slave nodes, the Bluetooth master module is in communication connection with the digital key module as a BLE master node, and the Bluetooth master module is connected with the Bluetooth slave modules through CAN/LIN lines. The BCM (body control module) is a control module with powerful design function, realizes discrete control function and controls a plurality of electrical appliances. The functions of the body BCM include: electric door and window control, central control door lock control, remote control anti-theft, light system control, electric rearview mirror heating control, instrument backlight adjustment, power distribution and the like.

BLE smart key's main function:

(1) the method realizes the DISCOVER and BLE broadcasting, scanning and connection establishment of the BLE host node and the mobile phone, and simultaneously completes the safety certification of a service layer.

(2) The sensible vehicle control function: the BLE master node receives the vehicle control instruction transmitted by the BLE of the mobile phone, and then directly controls the vehicle control instruction of unlocking/locking/waiting of the vehicle through the CAN bus according to the CAN vehicle control message command of the vehicle factory.

(3) Noninductive vehicle control function: BLE follows node monitoring cell-phone position, acquires bluetooth signal strength RSSI, through BLE positioning algorithm, calculates the position region of current car owner, and the initiative realizes PEPS connects shutting and a car one-key start-up function.

Referring to a schematic diagram of a data transmission method of a BLE smart key CANFD shown in fig. 1, taking a mobile phone as a carrier of a digital key module as an example, an unlocking/locking process of the BLE smart key on a car body BCM is as follows:

1. starting APP software and Bluetooth functions in the mobile phone, and carrying out BLE scanning and sending unlocking/locking instructions and the like by the mobile phone;

2. the method comprises the steps that after a BLE host node receives BLE broadcast of a mobile phone, BLE pairing is carried out, then BLE protocol stack connection is carried out, and safety authentication is carried out;

3. after the safety certification is passed, the BLE main node CAN receive the unlocking/locking instructions and the like sent by the mobile phone and send the unlocking/locking instructions and the like to the body BCM through the CAN bus, so that the vehicle control function is realized.

4. The BLE slave node monitors the position of the mobile phone through Bluetooth, and acquires the RSSI (received signal strength indicator) of the Bluetooth signal after acquiring the position information of the mobile phone close to the car body; the BLE slave node transmits the Bluetooth signal strength RSSI to the BLE main node through the CAN bus, the position of the mobile phone is calculated by the BLE main node through a corresponding BLE algorithm, and the BLE main node realizes a vehicle control function through unlocking/locking instructions and the like sent to the BCM of the vehicle body through the CAN bus according to an operation result.

The DATA transmission method for the BLE smart key CANFD is applicable to a DATA frame with DATA less than 64 bytes, which causes the method to have certain limitations. With the development of technology, for the safety and reliability of bluetooth communication, a higher level of BLE safety authentication content is required between a BLE smart key and a BLE control system, and data transmission between the BLE smart key and the BLE control system is mostly based on ciphertext transmission, and generally one data packet exceeds 200 bytes. In the existing CANFD communication specification standard, a maximum DATA size of 64 bytes is supported by a DATA frame, and ciphertext transmission of more than 200 bytes cannot be satisfied.

Disclosure of Invention

In order to solve the technical problems existing in the prior BLE intelligent key CAN FD when data transmission of higher-level BLE security authentication content is carried out, the invention provides a method for splitting a sending end and recombining a large data ciphertext packet transmitted in two directions on a CAN FD channel and realizing a protection method of functional security E2E on a transmission protocol.

In order to achieve the purpose, the invention adopts the technical scheme that:

a big data transmission method of a BLE intelligent key CANFD is characterized in that: an ZCU controller is arranged between the BLE intelligent key system and the vehicle body BCM and is used as an intermediate node of the cryptograph big data bidirectional transmission function of BLE safety authentication between the BLE intelligent key system and the vehicle body BCM; the BLE intelligent key system is in communication connection with the ZCU controller; the BLE intelligent key system comprises a movable digital key module, a BLE main module and a BLE slave module which are arranged on the vehicle; the BLE master module is used as a BLE master node and is in communication connection with the digital key module, and the BLE master module is connected with each BLE slave module through a CAN/LIN bus;

the digital key module establishes Bluetooth communication with the BLE main module, and the digital key module scans BLE and sends BLE broadcast; the BLE main node performs BLE pairing after receiving BLE broadcasting of the digital key module, performs BLE protocol stack connection, unpacks large data ciphertext packets with the size exceeding 64 bytes to form a plurality of frames of single-frame authentication ciphertext with the size smaller than 64 bytes, and sends the authentication ciphertext to the ZCU controller;

ZCU the controller receives the authentication ciphertext sent by the BLE host node, packages the authentication ciphertext into a big data ciphertext package exceeding 64 bytes, performs security authentication, unpacks the generated authentication ciphertext big data to form a plurality of single-frame authentication ciphertexts with the frame size smaller than 64 bytes after the security authentication is completed, and sends the single-frame authentication ciphertexts back to the BLE host node;

after the safety certification is passed, the BLE master node can receive the vehicle control instruction sent by the digital key module and send the vehicle control instruction to the ZCU controller; ZCU the controller receives the vehicle control instruction, sends the vehicle control instruction to the vehicle body BCM, realizes the vehicle control function.

Further, the BLE slave module monitors the position of the digital key module through a Bluetooth signal, and acquires the Bluetooth signal strength RSSI after acquiring the position information of the digital key module close to the vehicle body; the BLE slave node transmits the Bluetooth signal strength RSSI to the ZCU controller, the ZCU controller calculates the position of the digital key module through a corresponding BLE algorithm, and the ZCU controller realizes a vehicle control function according to a vehicle control instruction sent to a vehicle body BCM by an operation result.

Further, the ZCU controller includes a can fd unpacking/packing component and a ZCU security component; the CANFD unpacking/packing component is used for splitting or combining a large data ciphertext packet which is transmitted between the BLE main node and the ZCU controller in a bidirectional mode on a CANFD channel at a transmitting end; and the ZCU security component receives the encrypted data sent by the CANFD unpacking/packing component for BLE security authentication and then sends the encrypted data back to the CANFD unpacking/packing component.

Further, the CANFD unpacking/packing component comprises the following steps of unpacking/packing according to a rule of UDS single frame/continuous frame/flow control frame when a big data ciphertext packet as a CANFD data packet exceeds 64 bytes, unpacking/packing into a data frame less than 64 bytes, and then retransmitting according to a format of CANFD; the CAN FD data packet comprises safety certification, vehicle control instructions and vehicle information return of the BLE module.

Further, the ZCU controller transmits the large data of the CAN FD to the BLE main node according to the following flow:

the method comprises the following steps that 1, a BLE main module performs polling counter pairing and CRC (cyclic redundancy check) on a BLE data frame received from a digital key module and encapsulates the BLE data frame into a CANFD (secure entry network data) data packet, the CANFD data packet is unpacked into a plurality of data frames in a CANFD format, and the data frames are sent to an ZCU controller frame by frame through a CANFD bus;

the ZCU security component of the controller in the process 2 or ZCU sequentially receives data frames in a CAN FD format sent by a BLE main module through a CAN FD bus, packages the data frames in the CAN FD format into big data ciphertext packets, verifies the data frames to judge whether retransmission is needed, and restores the data frames if the data frame verification result is correct;

the controller in the process 3 or ZCU performs polling counter pairing and CRC check on ZCU data frames after the data frames are restored and authenticated, encapsulates the data frames into a CANFD data packet, unpacks the CANFD data packet into a plurality of data frames in a CANFD format, and sends the data frames to a BLE main module frame by frame through a CANFD bus;

and 4, sequentially receiving data frames sent by the BLE main module through the CAN FD bus, packaging the data frames in the CAN FD format into big data ciphertext packets, checking the data frames to judge whether retransmission is needed, restoring ZCU data frames if the data frame checking result is correct, and finally sending ZCU data frames to the digital key module through Bluetooth to complete the whole BLE security authentication process.

Further, the BLE intelligent key system is in communication connection with the ZCU controller through a CANFD communication protocol bus; the BLE master module and each BLE slave module are connected through a CAN/LIN bus; the BLE main module is connected with the digital key module through Bluetooth communication.

The digital key module comprises a carrier which is a mobile terminal such as a mobile phone, a bracelet and a digital key.

From the above, compared with the prior art, the invention has the following advantages:

1) the BLE intelligent key system unpacks/packs data through the CANFD channel, single-frame bidirectional transmission of big data on the CANFD bus is achieved, the problem of transmission of ciphertext data packets with more than 200 bytes on the CANFD bus is solved, and the BLE intelligent key system can use higher-level BLE safety authentication content conveniently;

2) in the unpacking/packaging process, the standard UDS specification is met; the compatibility is good, and the difficulty and the cost of updating and upgrading the system are greatly reduced;

3) the protocol protection of E2E is realized on the protocol, and a CRC (cyclic redundancy check) mechanism is added to ensure the stable and fast transmission of data.

Drawings

Fig. 1 is a schematic system structure diagram of a conventional BLE smart key system and a vehicle body BCM.

Figure 2 is a schematic system structure diagram of a BLE smart key system, ZCU controller and vehicle body BCM.

Fig. 3 is a schematic structural diagram of the ZCU controller according to the present invention.

Figure 4 is a ladder flow diagram of the ZCU controller transferring large data for the CANFD of the BLE master node.

Figure 5 is a bluetooth data structure definition table for data transmission between the handset and the BLE master module.

Fig. 6 is a definition table of TLV data structure.

Figure 7 is a table of a format of a CANFD diagnostic message between a handset and a BLE master module.

The reference numbers illustrate: 1-digital key module, 2-BLE master module, 3-ZCU controller, 4-body BCM, 5-BLE master node, 6-BLE slave node, 7-CAN FD unpacking/packing assembly, 8-ZCU safety assembly.

Detailed Description

The following detailed description of the invention and its advantageous effects are described in detail with reference to the accompanying drawings and preferred embodiments. In the present embodiment and the accompanying drawings, for convenience of detailed description, a mobile phone is used as a carrier of the digital key module 1, and an APP for driving the digital key module 1 to operate is installed on the mobile phone; the automobile is used as a carrier of the Bluetooth master module and the Bluetooth slave module. The functions of the vehicle body BCM5 include: electric door and window control, central control door lock control, remote control anti-theft, light system control, electric rearview mirror heating control, instrument backlight adjustment, power distribution and the like. ZCU controller 3 is an in-vehicle domain controller. BLE is an english abbreviation for bluetooth. BLE herein means "bluetooth".

Referring to fig. 2 to 4, in the big data transmission method of the BLE smart key CANFD according to the preferred embodiment of the present invention, a ZCU controller 3 is provided between a BLE smart key system and a car body BCM5, and is used as an intermediate node of a cipher text big data bidirectional transmission function of BLE security authentication between the BLE smart key system and the car body BCM 5; the BLE intelligent key system is in communication connection with the ZCU controller 3 through a CANFD communication protocol bus, and a security authentication encryption and decryption algorithm and a key storage management core device encryption IC are arranged in the ZCU controller 3; the BLE intelligent key system comprises a movable digital key module 1, a BLE main module 2 and a BLE slave module, wherein the BLE main module and the BLE slave module are both arranged on the vehicle; the BLE master module 2 is used as a BLE master node 5 to communicate with the digital key module 1 through Bluetooth, and the BLE master module 2 is connected with each BLE slave module through a CAN/LIN bus;

the digital key module 1 establishes Bluetooth communication with the BLE main module 2, and the digital key module 1 scans BLE and sends BLE broadcast; the BLE master node 5 performs BLE pairing after receiving BLE broadcasting of the digital key module 1, performs BLE protocol stack connection, unpacks large data ciphertext packets with the size exceeding 64 bytes to form a plurality of frames of single-frame authentication ciphertext with the size smaller than 64 bytes, and sends the authentication ciphertext to the ZCU controller 3 through a CANFD bus;

ZCU the controller 3 receives the authentication ciphertext sent by the BLE master node 5, packages the authentication ciphertext into a big data ciphertext packet exceeding 64 bytes, performs security authentication, unpacks the generated authentication ciphertext big data to form a plurality of single frame authentication ciphertexts with the length less than 64 bytes after the security authentication is completed, and sends the single frame authentication ciphertexts to the BLE master node 5 through the CANFD bus;

after the safety certification is passed, the BLE master node 5 can receive the vehicle control instruction sent by the digital key module 1 and send the vehicle control instruction to the ZCU controller 3 through the CANFD bus; ZCU the controller 3 receives the vehicle control command, and sends the vehicle control command to the BCM5 through the CAN bus to realize the vehicle control function;

the BLE slave module monitors the position of the digital key module 1 through a Bluetooth signal, and acquires the Bluetooth signal strength RSSI after acquiring the position information of the digital key module 1 close to the vehicle body; the BLE slave node 6 transmits the Bluetooth signal strength RSSI to the ZCU controller 3 through a CAN FD bus, the ZCU controller 3 calculates the position of the digital key module 1 through a corresponding BLE algorithm, and the ZCU controller 3 transmits a vehicle control instruction to the vehicle body BCM5 through a CAN bus according to the operation result to realize the vehicle control function.

Referring to fig. 2, further, ZCU controller 3 includes a can fd unpacking/packing assembly 7 and a ZCU security assembly 8; the CANFD unpacking/packing component 7 splits or combines a large data ciphertext packet which is transmitted between the BLE host node 5 and the ZCU controller 3 in two directions on a CANFD channel at a transmitting end; and encrypted data sent by the can fd unpacking/packing component 7 is received by ZCU security component 8 for BLE security authentication and then sent back to the can fd unpacking/packing component 7.

Referring to fig. 2 to 4, further, the CANFD unpacking/packing component 7 includes the following steps, when a big data ciphertext packet as a CANFD data packet exceeds 64 bytes, unpacking/packing according to the UDS single frame/continuous frame/flow control frame rule, unpacking into a data frame less than 64 bytes, and then retransmitting according to the format of CANFD; the CAN FD data packet comprises safety certification, vehicle control instructions and vehicle information return of the BLE module.

Referring to fig. 3-4, further, the ZCU controller 3 transmits the large data of the can fd to the BLE master node 5 as follows:

the process 1 is that a BLE main module 2 performs polling counter pairing and CRC check on BLE data frames received from a digital key module 1 and encapsulates the BLE data frames into a CANFD data packet, unpacks the CANFD data packet into a plurality of data frames in a CANFD format, and then sends the data frames to an ZCU controller 3 frame by frame through a CANFD bus;

in the process 2, the ZCU security component 8 of the ZCU controller 3 sequentially receives data frames in a CANFD format sent by the BLE main module 2 through a CANFD bus, and then packages the data frames in the CANFD format into big data ciphertext packets, and then performs data frame check as to determine whether retransmission is needed, and performs data frame restoration if the data frame check result is correct;

in the process 3, the ZCU controller 3 performs polling counter pairing and CRC check on ZCU data frames after the data frames are restored to form an authenticated ZCU data frame, encapsulates the authenticated ZCU data frame into a CANFD data packet, unpacks the CANFD data packet into a plurality of data frames in a CANFD format, and sends the data frames to the BLE main module 2 frame by frame through a CANFD bus;

and 4, sequentially receiving data frames sent by the BLE main module 2 in a CANFD format through a CANFD bus, packaging the data frames in the CANFD format into large data ciphertext packets, checking the data frames to judge whether retransmission is needed, restoring ZCU data frames if the data frame checking result is correct, and finally sending ZCU data frames to the digital key module 1 through Bluetooth to complete the whole BLE security authentication process.

The digital key module 1 includes a mobile terminal such as a mobile phone, a bracelet, and a digital key as a carrier, and is preferably a mobile phone. And adding a polingcounter and CRC (cyclic redundancy check) check to a transmission protocol of the data frame to realize the communication protection of the functional security end-to-end (E2E). The parts not specifically described herein are the contents of the relevant parts of the existing bluetooth communication or industry standard communication protocol, and the application is not listed for brevity.

When the method is used, a large data transmission program of the CANFD can be written according to the flow shown in fig. 4 in the data transmission programs of the CANFD of the digital key module 1 and the bluetooth main module, and the large data transmission program can be operated along with the system. In this embodiment, the definition of BLE packets when writing a program is as follows:

one, BLE packet definition

Referring to fig. 5, the structure of data transmission between the handset and the BLE master module 2 is defined as shown in the table in fig. 5, and the length of an entire data packet varies from several tens of bytes to several hundreds of bytes.

II, definition

A large amount of data communication exists between the BLE main module 2 and the BLE ZCU controller 3, including all processes of authentication and signature verification, if signals are increased by referring to CAN communication, a plurality of message IDs and signals are increased, and when data change or upgrading exists subsequently, communication matrixes need to be revised again, software of a CAN driving layer is updated simultaneously by the two controllers ZCU controller 3 and the BLE main module 2, the development period is long, unnecessary workload is increased by changing other departments, only a pair of interactive CAN messages need to be increased by introducing TLV format definition messages, the Bluetooth data signal change and the subsequent service re-development CAN be flexibly realized, the flexibility is high, and the CAN driving re-development of the ZCU controller 3 is not involved when data content is changed.

Referring to the tables shown in fig. 6-7, TLVs are a variable format, meaning: type, length, Value. Type: this field is information about the tag and encoding format; length: this field is the length of the defined value; value: the field indicates the actual value. The Length of Type and Length is fixed, and generally, the Length is 2 or 4 bytes (an unsigned short or an unsigned long, which is specifically used for uniform encoding and parsing, and an unsigned long Type is taken herein); the Length of Value is specified by Length;

the Bluetooth data packet is packed in a VALUE field of the TLV, and the length of the Bluetooth data packet is different from dozens of bytes to hundreds of bytes, so that after the TLV is packed, the length of the whole data packet is 4 bytes on the basis of the Bluetooth data packet. However, a data packet of the CANFD can only transmit 64 bytes at most, so the application unpacks the data packet with the extent exceeding 64 bytes according to the standard UDS method.

Three, CANFD UDS unpacking/packaging

The BLE main module 2 and the ZCU controller 3 are transmitted through a CANFD message, the maximum length of each frame of message is 64 bytes, when the transmission of the message is greater than 64 bytes, the signal needs to be unpacked into multi-frame transmission, and the protocol of the multi-frame transmission meets the unpacking and packing protocol of 15765.

The invention is not limited in any way by the above description and the specific examples, which are not limited to the specific embodiments disclosed and described above, but rather, several modifications and variations of the invention are possible within the scope of the invention as defined in the claims.

Claims

1. A big data transmission method of a BLE intelligent key CANFD is characterized in that: an ZCU controller is arranged between the BLE intelligent key system and the vehicle body BCM and is used as an intermediate node of the cryptograph big data bidirectional transmission function of BLE safety authentication between the BLE intelligent key system and the vehicle body BCM; the BLE intelligent key system is in communication connection with the ZCU controller; the BLE intelligent key system comprises a movable digital key module, a BLE main module and a BLE slave module which are arranged on the vehicle; the BLE master module is used as a BLE master node to communicate with the digital key module through Bluetooth, and the BLE master module is connected with each BLE slave module through a CAN/LIN bus;

2. The big data transmission method of BLE smart key can fd of claim 1, characterized by: the BLE slave module monitors the position of the digital key module through a Bluetooth signal, and acquires the Bluetooth signal strength RSSI after acquiring the position information of the digital key module close to the vehicle body; the BLE slave node transmits the Bluetooth signal strength RSSI to the ZCU controller, the ZCU controller calculates the position of the digital key module through a corresponding BLE algorithm, and the ZCU controller realizes a vehicle control function according to a vehicle control instruction sent to a vehicle body BCM by an operation result.

3. The big data transmission method of BLE smart key can fd of claim 1, characterized by: the ZCU controller includes a CANFD unpacking/packing component and a ZCU security component; the CANFD unpacking/packing component is used for splitting or combining a large data ciphertext packet which is transmitted between the BLE main node and the ZCU controller in a bidirectional mode on a CANFD channel at a transmitting end; and the ZCU security component receives the encrypted data sent by the CANFD unpacking/packing component for BLE security authentication and then sends the encrypted data back to the CANFD unpacking/packing component.

4. The big data transmission method of BLE smart key CAN FD of claim 3, wherein: the CANFD unpacking/packing component comprises the following steps that when a big data ciphertext serving as a CANFD data packet exceeds 64 bytes, unpacking/packing is carried out according to a rule of a UDS single frame/continuous frame/flow control frame, the data frame which is smaller than 64 bytes is unpacked, and then the data frame is retransmitted according to a format of CANFD; the CAN FD data packet comprises safety certification, a vehicle control command and vehicle information return of a BLE module.

5. The big data transmission method of BLE smart key CAN FD of claim 4, wherein: the ZCU controller transmits the CAN FD big data to the BLE main node as follows:

the ZCU security component of the controller in the process 2 and ZCU receives data frames in a format of CANFD sent by a BLE main module in sequence through a CANFD bus, and then packages the data frames in the format of CANFD into big data ciphertext packets, and then performs data frame check to determine whether retransmission is needed, and performs data frame restoration if the data frame check result is correct;

6. The big data transmission method for BLE smart key CAN FD according to any one of claims 1 to 5, wherein: the BLE intelligent key system is in communication connection with the ZCU controller through a CANFD communication protocol bus; the BLE master module and each BLE slave module are connected through a CAN/LIN bus; the BLE main module is connected with the digital key module through Bluetooth communication.