Design and Implementation of CAN Data Compression Algorithm

Controller area network (CAN) was designed for multiplexing communication between electronic control units (ECUs) in vehicles and many high-level industrial control applications. Its cost, performance and reliability provide for tremendous flexibility in system design. When a CAN bus is overloaded by the increased number of ECUs connected to the CAN bus, both the waiting time for low priority CAN messages and the error probability of data transmission are increased. Thus, it is desirable to reduce the frame length since the time duration for the data transmission is proportional to CAN frame length. In this paper, we present a CAN message compression method to reduce the CAN frame length. Experimental results show that the CAN transmission data can be compressed up to 76% by the proposed method. By using an embedded test board, it is shown that 64-bit EMS CAN data compression can be performed within 0.16ms and consequently the proposed algorithm can be used in automobile applications without any problem.