Concatenated space-time block coding with trellis coded modulation using a delay processor

It is known that tail-biting codes T´ constructed from trellis coded modulation (TCM) with a delay processor can achieve large minimum Euclidean distances. In this paper, concatenated space-time block coding (STBC) with T´ for multiple-input multiple-output (MIMO) and MIMO-OFDM (orthogonal frequency-division multiplexing) systems is investigated. We propose an improved system which is implemented by inserting a specific block interleaver between the encoders of coded modulation and STBC. We also propose sliding-window-type iterative decoding using partial hard-decision feedback (SW-IDPHF) with low complexity to decode T´, which provides better error performance as compared to sliding-window-type iterative decoding using full hard-decision feedback (SW-IDFHF). In addition, we apply sliding-window-type iterative decoding using soft-decision feedback (SW-IDSF) to T´ for improved error performance. The decoder of concatenated system based on T´ can converge faster and provide better ultimate error performance as compared to the case of BICM under various channel conditions for either MIMO or MIMO-OFDM systems.