基于OBDD的航空电子网络可靠性分析

摘要

针对航空电子网络通信任务的实时性需求,建立具有时延约束的面向任务的网络可靠性模型,并从共因失效(common cause failure,CCF)的角度分析了部件故障相关性,提出一种基于有序二叉决策图(ordered binary decision diagram,OBDD)的航空电子网络可靠性评价方法——时延约束边扩张算法.算法结合时延约束,利用边扩张构建网络OBDD,递归遍历OBDD结构计算部件故障统计独立条件下航空电子网络可靠度,并在此基础上引入CCF分析,利用同一OBDD结构综合评价航空电子网络可靠性.通过实例阐述了算法的原理,实验表明算法能有效评价航空电子网络的可靠性.%Avionics networks work in a real-time manner where the intended functions should be performed before time deadline. To assess the reliability of an avionic network comprehensively, the metric delay as well as the common-cause failures are taken into consideration and a task-based model with delay constraints is built. Moreover, an efficient ordered binary decision diagram (OBDD) based approach, named time-constraint edge expansion, is proposed which incorporates delay constraints into the edge expansion diagram to construct OBDD and analyzes network reliability with common-cause failures on the basis of the original OBDD. A sample net-work is shown to illustrate the evaluation procedure using the proposed approach. The experiment results verify the correctness and efficiency of the approach in reliability analysis for avionics networks.