A Modified Approach on MMSE MIMO Interference Cancellation Detection of Free Space Optical Communication

In this paper, an novel MMSE MIMO detector is proposed with respect to MMSE MIMO channel estimation on free space optical communications(FSO). We will show how a two-step MMSE MIMO estimator can be used to facilitate packet detection as well as to provide superior bit error rate performance. This proposed detector takes channel estimation errors into account by the statistical characteristics of MMSE MIMO channel estimation. When compared with existing soft-output MMSE MIMO detector, simulation results show that the proposed novel detector can remarkably reduce the residual error floor due to the channel estimation errors, while achieving significant performance gain at the cost of negligible increase of complexity. We will show how this approach significantly improves packet detection and how the overall solution approaches the performance of the classical MMSE estimator. The simulation results shows that MMSE MIMO detector based on FSO can reduce the atmospheric scintillation turbulence effects on bit error rate of atmospheric. When the number of transmit antennas is fixed, the bit error rate will decrease with the increasing number of receiving antenna; when the number of transmit antennas is not fixed, as the number of tranmit antennas increases, the channel capacity will increase