Abstract

It has been shown that at least N² basic space switches have to be used to support nonblocking interconnects between N nodes in an environment where both the point-to-point and multicasting communications are required. The objective of this research is to explore the possibility of using optical parallelism to reduce such a switching complexity bound. Recently, we have shown that a k-dimensionally multiplexed switching network could ultimately reduce such a bound to O(N^1+1/k) [1], For k=4, we intend to use space, spatial-frequency, time, and temporal-frequency dimensions, and multiplex them one on top of the other to achieve the interconnect goal. In the talk, a basic theory underlining the reduced-complexity networking principles will be briefly reviewed. A free-space and compact k=2 (space and spatial-frequency multiplexed) interconnect architecture with a complexity of O(N^3/2) is then described. It will be shown that the implementation of the architecture only requires space-invariant optical components. To extend the network capacity from k=2 to k=4, as long as the system’s space/spatial-bandwidth product and time/temporal-bandwidth product permit, the wavelength multiplexed and time-multiplexed channels can simply be added to the previously described k=2 system. It will be shown that only O(N^5/4) basic switches are used in this network to achieve the non-blocking communication goal of performing the multicasting operation. An added advantage is that the architecture relaxes the switching complexity at each dimension, e.g. a network of N=10,000 only requires to use 10 spatial pixels, with 10 multiplexed angles at each pixel, with 10 wavelengths per angle, and with 10 timeslots per each wavelength. The proposed concept is experimentally verified using a cascade of two multichannel acousto-optic Bragg’s cells.

© 1993 Optical Society of America