Capacity and Error Performance Verification of Multi-Antenna Schemes in Radio-over-Fiber Distributed Antenna System

A radio-over-fiber distributed antenna system permits larger physical separation between antennas in a wireless system’s infrastructure; this investigation verifies that improved performance – lower error rates and higher capacities – can thus be achieved. In this paper, specific single-input multiple-output (SIMO), multiple-input single-output (MISO) and multiple-input multiple-output (MIMO) algorithms are compared in an experimental radio over fiber system, using user-defined processing functions for the signals. It is shown that significantly reduced symbol error rate (SER) and modestly increased capacity is achieved for a wireless 1x2 SIMO uplink using the maximal ratio combining (MRC) processing algorithm and 2x1 MISO downlink using the Alamouti space time block coding (STBC) scheme. Further, SER is reduced for a downlink 2x2 wireless MIMO using the zero-forcing algorithm while, most importantly, greatly increased capacity is achieved through the spatial multiplexing gain.