Space-time bit-interleaved coded modulation with an iterative decoding strategy

Abstract

A space-time coding approach for wireless communications deploying multiple transmit and multiple receive antennas is presented. The approach is based on the concatenation of a convolutional encoder, a bit interleaver, and a space-time signal constellation mapper that combines multi-level/phase modulation with multiple transmit antennas. The decoding strategy follows an iterative (turbo-like) algorithm where soft information is exchanged between a soft-in soft-out demapper and a soft-in soft-out convolutional decoder. It is applicable with one or more receive antennas, and shows that spectral efficient/reliable communications are possible with few iterations. We address the performance analysis in both block and fast flat Rayleigh fading in order to provide insight into the space-time code construction criteria for the approach that we propose. Finally, simulation results are reported for schemes with 2 bits/s/Hz and 4 bits/s/Hz.