Fault-Tolerant Techniques for Radiation Environments

This paper reports on a study made on the use of fault-tolerant systems in radiation environments for radiation hardening and hardness assurance purposes. The fault-tolerant systems studied in depthare TMR, TMR/Simplex, Switching Redundancy, Self-Purging Redundancy, and Radial Logic. Failure distributions were obtained for a number of components and for various radiation environments. These were used to graph radiation related indicators as a function of radiation level. One indicator relates to radiation hardness and a second relates to hardness assurance. The effects of imperfect switches and voters and of system size and system sectioning were considered. Finally, the chosen systems were ranked with respect to radiation hardness and hardness assurance.