New approach for coded layered space-time OFDM systems

In this paper, we investigate coded layered space-time architectures for frequency-selective fading MIMO-OFDM channels. We start with a comprehensive signal model including error propagations. Based on the signal model, we derive an improved signal detector in the mean-square-error criterion. We also describe the optimal soft bit log-likelihood ratio (LLR) value computation method by taking the decision errors into account for soft-input Viterbi decoder. We compare the proposed scheme with the conventional V-BLAST system and show that significant performance improvement at high data rates can be attained.