A pre-emptible real-time SpaceWire on-board network

To build unified on-board communication infrastructure based on SpaceWrie, research should be done to guarantee the deterministic and real-time performance of message transmission. To overcome the lack of flexibility in traditional time-triggered communication, a modified time-triggered SpaceWire network which supported the broadcasting of communication task transmission identifier was proposed. On this basis, a non-destructive pre-emptible communication mechanism was built and the application of classical processor real-time scheduling algorithm to communication task scheduling was discussed. At last, the transmission delay performance was analyzed and compared among event-triggered, traditional time-triggered and non-blocking real-time SpaceWire communication mechanisms. The research shows that this communication mechanism can reduce the worst-case end-to-end delay, and is suited for the scheduling of communication tasks with various priorities.