On bit interleaved space time coded modulation

Abstract

The coding for the wireless channel is the main topic of this thesis. Mainly, single user transmission over one or more antennas is considered in the first part, where we considered multidimensional bit interleaved coded modulation with iterative decoding using 8-PSK constellations. We showed that an optimum multidimensional labeling with a designed interleaver outperforms the two dimensional bit interleaved coded modulation with iterative decoding in the whole SNR region when modulation doping is used to compensate for the loss at the low SNR regions. In addition to this, a new interleaver design is introduced. Then we consider the two transmit antennas case and we propose multidimensional constellation labeling for bit interleaved space time coded modulation with iterative decoding using the Alamouti scheme and one receive antenna. The labeling of two 16-QAM signals are designed jointly and optimized using the reactive tabu search algorithm with a slight modification in the fitness function of the two dimensional labeling. The proposed multidimensional labeling provided a large coding gain compared to the best known two dimensional labeling. For the case of two transmit antenna we consider the transmission over two uncorrelated frequency bands and construct a simple 2 × 2 × 2 full-rate full-diversity space time frequency code based on constellation rotation. In the second part the multiuser scenario from information theoretic point of view is discussed.