Multiple-Input Multiple-Output Multiple-Mode OFDM With Index Modulation

Multiple-mode orthogonal frequency division multiplexing with index modulation (MM-OFDM-IM) has been proposed as a novel IM technique, which conveys information via the permutation of multiple distinguishable constellations. In this paper, we propose a novel multiple-input multiple-output MM-OFDM-IM (MIMO-MM-OFDM-IM) scheme by combining MM-OFDM-IM and MIMO to take advantage of both techniques collectively. The low complexity detections, such as minimum mean square error (MMSE) Viterbi-like and MMSE subcarrier-wise log-likelihood ratio (MMSE-LLR), are proposed to largely reduce the receiver detection complexity. Besides, the theoretical analyses on bit error rate (BER) is also derived in closed-form to evaluate the performance of MIMO-MM-OFDM-IM. Considering different system configurations, it is shown via Monte Carlo simulations that the proposed MIMO-MM-OFDM-IM scheme not only achieves higher SE but also provides better error performance than the conventional schemes.