High performance, reliable and flexible computing payload for space missions

In this paper, we discuss the design concepts of a high performance, reliable and flexible computing payload suitable for space missions. This payload is used as a secondary payload onboard X-Sat, a microsatellite currently being developed by Nanyang Technological University and is scheduled for launch in 2006. In brief, parallelism is employed in the system design to achieve high computing performance. Field-programmable gate arrays are used as the basis for interconnecting the processors. This provides users with the flexibility to develop different processor interconnection topologies to suit the varying needs of different parallel applications running on the payload. To achieve high system reliability at minimal cost, an appropriate mixture of commercial-off-the-shelf and radiation-hardened components are used in its implementation. In addition, we also introduce a processor remapping algorithm. This algorithm is used in the construction of a reconfigurable interconnection network for the payload, which can reconfigure itself dynamically to produce a 4/spl times/4 mesh network in the presence of a processor failure. This ability to reconfigure "on the fly" minimizes the payload's downtime due to failures and hence, provides the satellite with a high degree of reliability.