在现代卫星设计中广泛使用的可重构现场可编程门阵列(FPGA),在空间高能粒子的影响下很容易产生单粒子翻转(SEU),从而功能紊乱甚至失效。在面向航天应用的FPGA设计中,必须采用容错设计技术来弥补器件本身抗辐射能力的不足。本文首先分析了有限状态机(FSM)的内部结构,并指出由于自身电路结构的特点,传统的FPGA容错设计方法应用于FSM时有一定的局限性。然后,针对基于FPGA的FSM容错设计技术进行了研究,根据现代FPGA的结构特点,提出了一种基于FPGA内置双端口随机存取存储器(RAM)、具有周期校验功能的FSM设计方案。经过可靠性分析和实验可以看出,与采用传统容错设计方法的FSM相比,采用本文方案构建的FSM在太空辐射环境下具有更高的长期可靠性、更小的FPGA资源占用量和更低的功耗。
Field programmable gate arrays(FPGAs),which are widely used in modern satellites,are sensitive to space radiation.The single event upset(SEU)caused by high-energy space particles can disturb the function of the reconfigurable FPGA,and even lead to design failure.Hence,FPGA fault tolerant design technology must be developed to make up for the insufficiency in radiation resistance of its components.This article first analyzes the structure of a finite state machine(FSM),which serves to reveal the drawbacks of traditional fault tolerant design technology for FSM.Then,the article presents a new type of periodicity checkout FSM based on the inner dual port random access memory(RAM)of FPGA.Finally,a reliability analysis is performed and an experiment made of the proposed FSM.The results show that,compared with the traditional FSM,the FSM we designed has higher long term reliability,smaller FPGA resource requirement and lower power consumption in an outer space radiative environment.