Design, analysis, and performance evaluation for BICM-ID with square QAM constellations in Rayleigh fading channels

We consider bit-interleaved coded modulation with iterative decoding (BICM- ID) for bandwidth-efficient transmission over Rayleigh fading channels, We propose the design criteria that utilize a large Hamming distance inherited in a low-rate code and a new labeling technique designed specifically for fading channels. This results in large coding gain over noniterative coded modulation and performance close to that of "turbo" coded modulation with l ess complexity, We also show that BICM-ID designed for fading channel usual ly has a very good performance over the additive white Gaussian noise (AWGN ) channel while the converse is difficult to achieve, When combined with si gnal space diversity, diversity order can be improved to twice the diversit y order of conventional BICM-ID; therefore, the code complexity can further be reduced while maintaining the same level of performance. Specifically, with the bandwidth efficiency of 2 bits/s/Hz over Rayleigh fading channels, a bit error rate (BER) of 10(-6) can be achieved with 16-QAM, a four-state rate 1/2 code at E-b/N-o of about seven dB, We also derive performance bou nds for BICM-ID with and without signal space diversity over Rayleigh fadin g channels, which can be easily extended for other types of fading channels .