A synchronization method for the avionic system interconnected by the local communication network

It is convenient and economic to utilize power line communication to establish interconnection network for avionics system. The avionics system is equipped with a large number of data acquisition equipment, which collects and records data of spacecraft operation and key components status. The time information of the data and the network synchronization are of great significance to the comprehensive monitoring of spacecraft. Given the processing delay of timing protocol, accumulated delay caused by multistage relay, this paper proposes to estimate the transmission delay by extending the data domain of beacon frame in media layer protocol and introduce the downlink timing confirmation frame in a hierarchical manner. As a result, the timing offset caused by protocol processing and sampling time deviation is reduced. Through simulation results, the synchro-nization accuracy of the proposed clock synchronization method can reach dozens of µ s, which can effectively guarantee the real-time synchronization of spacecraft data acquisition.