A generalized simplified ML decoder of orthogonal space-time block code for wire-less communications over time-selective fading channels

We propose a novel generalized simplified maximum-likelihood (ML) decoder of orthogonal space-time block code (OSTBC) Ill for wireless communications over time-selective fading channels. The proposed decoder computes the decision statistics based on the channel state information ( SI) and completely -removes the mter7transmit-antenna interference (ITAI) and provides diversity advantage when the channel varies from one signaling interval to another. It is shown that when the channel is quasi-static, the proposed decoder becomes the optimum; ML decoder for OSTBC. We derive a tight theoretical upper bound for bit error probability of the proposed decoder We. show theoretically that the proposed decoder does not exhibit error floors at high signal-to-noise ratios (SNRs) like the decoder proposed in [5]. Simulation results for various channel-fading rates are presented to verify our theoretical analysis and demonstrate robust performance of the proposed decoder.