基于时钟偏斜的DIMA系统通信调度方法

A Scheduling Method for DIMA Networking System Based on Clock Skew

针对分布式集成的DIMA网络系统提出一种基于时钟偏斜的时间触发通信调度方法。该方法在考虑时钟同步误差和时钟漂移造成的时钟偏斜情况下,对时间触发消息流传输路径相邻上下级联设备的调度窗口进行紧密排布,在时钟偏斜误差范围内实现了时间触发消息的无冲突传输。案例表明,该调度算法实现的消息传输时延与消息最小传输时延一致,保障了时间触发消息端到端传输的确定性;即使考虑时钟偏斜影响,采用该算法所带来的传输延时误差不超过5μs,具有接近消息最好传输延时的保障能力。

A time-triggered communication scheduling method for distributed integrated modular avionics （DIMA） networking system is proposed on the basis of clock skew. Through closely arranging scheduling windows of adjacent cascading equipment on the path of time-triggered traffic flow, contention-free transmission is realized within the allowable range of clock skew, considering the clock skew caused by synchronization error and clock drift. An example is presented to demonstrate that traffic transmission latency achieved by the designed scheduling algorithm is consistent with the best-case transmission latency, which guarantees the end-to-end deterministic transmission for time-triggered traffic flows. It also proves that transmission latency error introduced by the scheduling algorithm will not exceed 5μs even considering the effect of clock skew, indicating that the algorithm ensures almost the best traffic transmission.