Simulation of Fault-Tolerant Space Systems Based on COTS Devices With GPSS

In microsatellite missions devoted to remote sensing, the cost-reliability issue is an important constraint. This paper presents a low-cost methodology to simulate the reliability of a system for the development of fault-tolerant space systems. This methodology does not rely on special facilities or expensive equipment and is focused on the onboard data handling (OBDH) system for microsatellite's remote sensing payloads with commercial off-the-shelf components. The method presented uses the general-purpose simulation system language to simulate the system's reliability when fault-tolerance techniques (FTTs) are applied to field-programmable gate arrays. The objective of the proposed methodology is to validate the mathematical model corresponding to the system's reliability or to compute the reliability when there is no mathematical model. Therefore, system-level decisions can be made, in order to select the most suitable components and develop the systems for microsatellites. Specifically, the OBDH computers must have a high reliability as a mandatory requirement for microsatellites. Moreover, the simulation provides statistics to support decisions regarding the necessary FTT to be implemented.