基于随机Petri网的机载软件更新系统性能评价

近年来,航电系统发展的趋势由联合式航电系统向综合化航电系统逐步演进,许多应用将原来专用集成电路实现的功能采用软件实现。软件更新系统在机载航电系统中的地位日益重要。提出了一种高效机载软件更新系统OBSUS,并运用随机Petri网理论对其性能评价。首先,提出了OBSUS的系统结构与组件间的通信协议。其次,根据OBSUS的系统结构与通信协议,建立了系统的随机Petri网模型。最后,对随机Petri网模型进行了瞬态概率分析,针对影响系统的诸多因素,如flash芯片烧写时间、数据传输丢包率和数据传输速率等,对系统的综合性能的影响进行了量化分析。仿真研究结果对于机载软件更新系统的结构与数据传输协议设计,以及如何提高系统性能,具有较强的指导意义。

Performance Analysis of On-board Software Update System Based on Stochastic Petri Nets

Nowadays on-board avionics systems are now changing from Federate Avionics to Integrated Modular Avionics(IMA),in which many functional components previously implemented by dedicated hardware are now realized by software.The advent of IMA makes the role of on-board software update system more important.An effective on-board software update system OBSUS was proposed and performance analysis was conducted for it.Firstly,the system architecture and communication protocol of OBSUS were purposed.Secondly,a stochastic Petri net model was constructed.Finally,transient analysis of the stochastic Petri net model was conducted,and how parameters,like the flash burning time,the packet drop rate,and the data transmission time,affected the system overall performance.Simulation results are helpful in designing system architecture and data transmission protocol,as well as improving system performance.