Fundamental limits on bandwidth, efficiency, and parallelism in all-optical and hybrid fan-in

Publisher Website
Google Scholar
Abstract
We present an investigation of relationships among the information bandwidth, the optical power efficiency, and the degree of parallelism for optical interconnectionarchitectures that employ optical fan-in. The foundation for these relationshipsis the Lagrange invariant, or, more specifically, the constant-radiance theorem.We show that, when restrictions imposed by the constant-radiance theorem arecombined with requirements on the probability of error, an upper limit isplaced on the bandwidth that is reduced as the fan-in ratio increases. Theselimitations are significantly more severe when optical fan-in is used to performanalog summations. We then define a measure of processing efficiency thattakes into account the influence of optical input power on the probabilityof error and is used to interpret the results.