Combined spatial multiplexing and diversity techniques for coded MC-CDMA systems with suboptimal MMSE-based receivers

We study several transmission techniques utilizing efficient forward error correction coding (FEC), space-time coding (STC), group-wise layered space-time (GLST) architectures, and, due to the inevitable complexity restrictions, suboptimal minimum mean squared error (MMSE) based receiver interfaces in the context of downlink multicarrier code-division multiple-access (MC-CDMA). Frequency-selective Rayleigh fading channels are assumed and the effect of spatial correlation on the system performance is considered. The results demonstrate that the recently proposed space-time turbo coded modulation (STTuCM) has a significant advantage over the more conventional transmission schemes combining orthogonal space-time block codes (STBCs) and single-antenna optimized turbo coded modulation also when the proposed GLST architectures and suboptimal, lower complexity receivers are utilized.