Adaptive Optimal Frame Length Analysis Based On The COSB Communication Protocol

Serial communication occupies less hardware resources, can significantly reduce thecommunication line costs, and ease of maintenance and many other advantages. It has beenwidely applied in the field of industrial control, power communication and intelligentinstruments. In industrial control, the data collected and control information must deliver tothe control center accurately and timely. How to develop a practical communication protocolthat easy to use and can greatly improve the serial communication efficiency; how to ensuredata exchange reliably, these problems are to be solved in the serial communication protocol.According to different application, data link layer protocol is designed into differentframe format. There are two basic methods: bit-oriented and byte-oriented. High Level DataLink (HDLC) is a typical bit-oriented protocol, while Point-to-Point Protocol (PPP) is abyte-oriented protocol. Both of them cannot guarantee transparency of valid data in theprotocol, must be adjusted according to the data content, which resulted in the huge overheadof the protocol.Based on Consistent Overhead Byte Stuffing (COBS) algorithm, a new industrial datacommunication protocol is proposed to improve the efficiency and reliability in industrial datatransmission, which can solve synchronization problems, shorten the frame length, as well assave bit resources. Under the circumstance of knowing bit error rate, the quantitativerelationship between the data frame error probability and the frame length is analyzed, so thatthe formula to calculate the optimal frame length is derived. In addition, the variable framelength feature of the proposed protocol is used to obtain an adaptive optimal frame lengthstrategy, which can further raise the efficiency of the communication. Simulation results andnumerical analysis verify the effectiveness of the proposed protocol with the optimal framelength.