导航卫星单粒子软错误影响建模与仿真方法

SEU soft error effect modeling and simulation method for navigation satellite

单粒子(SEU)软错误是导致卫星中断、影响卫星可用性的重要因素。针对SEU软错误在导航卫星内部的失效传播过程描述与影响评估问题,提出一种基于有限状态机(FSM)理论/Stateflow的软错误影响传播过程建模方法,阐述了构建软错误传播过程有限状态机模型的基本元素与原则,并针对导航卫星特点提出软错误影响传播与防护恢复策略的建模思路。利用Stateflow仿真得到单星可用度与平均任务中断时间,分析了多种恢复策略时间对整星可用性指标的影响;并通过构建MATLAB与STK联合仿真平台,由单星软错误传播仿真结果得到星座位置精度因子(PDOP)可用性指标,从而评估了SEU软错误在整星与星座2个层级的影响。

Single event upset（ SEU） soft error is one of the most important factors that affect the reliability and availability of satellite. To analyze and evaluate the SEU soft error propagation and effect in navigation satellite system,a novel finite-state machine（ FSM） / Stateflow modeling method is proposed,where the basic model elements and modeling principles combined with protection and recovery strategies in satellite are presented. Through the simulation based on Simulink / Stateflow platform,the availability of satellite and mean task interruption time are obtained,and the effects of several recovery strategies on the availability of satellite are analyzed; moreover,a co-simulation between MATLAB and STK is conducted to evaluate the constellation positioning dilution of precision（ PDOP） availability obtained from the simulation result of single satellite soft error propagation,which reflects the impacts of SEU soft error on both single satellite and constellation.