Reconfigurable systems: A generalization of reconfigurable computational strategies for space systems

Space may be the final frontier for the application of reconfigurable technologies. With the successful adoption of anti-fuse FPGAs in a number of spacecraft systems and improved knowledge and mitigation options for single-event phenomena, interest in exploiting reconfigurable (SRAM-based) FPGAs is growing. use is controversial, as the same features that provide seemingly unbounded flexibility may also be viewed as a risk factor. Fault detection and containment approaches, combined with sufficiently robust configuration setting and checking approaches, will provide greater confidence in the use of reconfigurable digital systems for a growing class of applications in space systems, which stand to benefit most from the ability to focus and reshape silicon (or other semiconductor) resources. The ability to reconfigure digital systems at varying degrees of granularity open exciting possibilities and suggests a natural extension of a DoD roadmap that has largely been based on fixed silicon. But relegating more digital functionality in systems to a malleable form is only a first step in a much larger possibility space. Beyond digital, approaches to reconfigure electronics in analog, microwave, and power electronic domains are emerging, leading to a more "totalistic" view of a reconfigurable system. This presentation will review a number of approaches, from software radios and chalcogenide-based neural networks, all of which offer to expand access of more electrical functionality to the direct influence of software or algorithmic thought processes, which could be implemented both autonomously and by remote control. The implications of the fully reconfigurable spacecraft are staggering, and an aggressive, open systems protocol is suggested for the 21st century. Finally, the issue of a hierarchy in adaptive systems is addressed. Systems can be considered fixed or adaptive, and the nature and extent of adaptive-ness can be at least qualitatively described. When a system has the trait of adaptive functionality, then a number of mechanisms for exploiting it can be suggested, ranging from the traditional off-line compilation of an FPGA bitstream to the more intriguing possibility of systems capable of self-organizing, even self-compiling a part of its inherent structure. This talk will propose a hierarchy of reconfigurable systems approaches.