Compact, scalable fiber optic cross-connect switches

Fiber optic cross-connect switches with high port count (N, with N/spl ges/32) are needed to handle the large numbers of wavelengths on each of large numbers of fibers in WDM systems. Optical cross-connects (OXCs) address this need directly, conveniently independent of bit rate and protocol. True N/spl times/N matrix OXCs require better per-crosspoint extinction performance than architectures using 2N each of 1/spl times/N switches, but N/spl times/N matrices can be far more compact, inexpensive and convenient since they do not need the N/sup 2/ internal fiber connections required to build OXCs from most 1/spl times/N switches. N/spl times/N matrices generally can also be scaled modularly into larger switches since they contain add and drop ports which 1/spl times/N architectures lack.