Receiver design for shot noise limited MIMO FSO/UV communication systems

In this paper we develop receiver design techniques for shot noise limited multiple-input multiple-output (MIMO) systems, specifically 2×2 MIMO non-line-of-sight (NLOS) free space optical (FSO) or ultraviolet (UV) communication systems, to illustrate the spatial multiplexing advantage of using a MIMO technique. The receivers considered are the zero forcing receiver, the minimum mean square error (MMSE) receiver, the maximum likelihood receiver (ML) for nondispersive channels, and the maximum-likelihood sequence estimation (MLSE) receiver and the maximum-a-posteriori (MAP) one shot receiver for dispersive channels. Performance expressions are derived for a 2×2 MIMO UV NLOS systems. The results indicate that the throughput can be significantly increased using a multibeam approach.