1. Department of Electronic Engineering, Tsinghua University, Beijing 100084, China;
2. Tsinghua Space Center, Tsinghua University, Beijing 100084, China;
3. Graduate School at Shenzhen, Tsinghua University, Beijing 100084, China
Abstract：Onboard switches in harsh space radiation environments can suffer serious reliability degradation. An interconnected parallel Clos (IP-Clos) network was developed to resist crosspoint faults and switch element faults. The IP-Clos consists of multiple Clos-network planes. Adjacent Clos-network planes are connected by inter-plane links to create multiple paths in each stage connecting to the next stage. Theoretical analyses demonstrate that the IP-Clos network has better reliability than parallel Clos networks for both crosspoint faults and switch element faults at the expense of the link overhead between switching elements. Numerical results indicate that the mean time to failure (MTTF) of an IP-Clos network in a geosynchronous orbit (GEO) satellite with space-grade field programmable gate arrays (FPGA) for crosspoint faults is more than 2.1×105 d. The MTTF for switch element faults is 6.86×103 d.
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2015, Vol. 55 
