The Advantages and Application Prospects of CAN FD Bus Technology for Vehicle Network Communication

Abstract

The fact that the degree of electronic control of automobiles increases rapidly has promoted the research of new vehicle-mounted buses. CAN FD bus, released by Bosch based on CAN bus, is the most promising one. Its biggest feature is that the data field length is increased to 64 bytes and it has a flexible and variable baud rate. It inherits many advantages of traditional CAN bus and it has made some improvements. Due to these changes, some advantages of CAN FD bus, compared with CAN bus, can be verified. Firstly, the data transmission efficiency and the synchronization of the signal transmission are greatly improved. Secondly, encryption design can be done to improve the security of communication. The CRC-16 check code is stored in the 63rd and 64th bytes. In addition, a CAN node can be compatible with a CAN FD node in the same network by letting the traditional CAN node enter two different working states, sleeping and waking up. Through experiments, it is found that compared with traditional CAN bus, CAN FD bus greatly reduces the load rate of the bus. Transmitting the same amount of information, as for physical nodes, CAN FD bus can reduce the bus load from 45.64% to 8.19%. Also it can significantly reduce the flash writing time based on the bus when the data field is extended to 64 bytes.