BER Analysis and Optimization of Generalized Spatial Modulation in Correlated Fading Channels

We propose and analyze a generalized spatial modulation scheme, where depending on the bits to be transmitted a certain data symbol as well as a certain beamforming vector is chosen. The receiver then has to estimate both the used beamforming vector and the transmitted data symbol for being able to reconstruct the originally transmitted bit sequence. We analyze our scheme theoretically by deriving a very tight upper bound on the average bit error rate (BER) for arbitrary symbol constellations and beamforming codebooks in correlated Rayleigh fading channels. Based on this bound, we determine a design criterion for optimizing the used beamforming codebook in presence of spatial correlation at the transmitter-side. Simulation results are shown to be in excellent agreement with our analytical calculated BERs and they illustrate the significant performance gains that can be obtained with our generalized scheme compared to conventional spatial modulation.