Optoelectronic FPGAs

Abstract

For several years, optics and photonics have been demonstrating their superiority over electronics in high-bandwidth, long-distance interconnects. Spurred by the advancing state of photonics technology, the level in the system hierarchy at which optical interconnect provides clear advantages over electrical interconnect appears to become distinctly lower as time moves on. In this paper, we focus on the use of optical logic level interchip interconnect. While, in general the advantages of optical interconnect at such low hierarchical levels currently are at best doubtful, there appear to exist important subclasses of components or systems where such advantages are much more tangible. We identify field-programmable gate arrays (FPGA) as a class of general-purpose very large scale integration components that would demonstrably benefit from the massive introduction of state-of-the-art optical interchip interconnections at the logic level. In this paper, we first identify the underlying reasons why we think that FPGAs form an exception to the general rule, and hence, why optical interconnects provide added value. We then briefly discuss some architectural issues to be resolved when building optoelectronic FPGAs, and present some of the ongoing work on the modeling of optoelectronic multi-FPGA systems.