BER Reduction for PSK-Based MM-OFDM-BIM with Two-Level Symbol Power

Phase-shift keying (PSK)-based multi-mode orthogonal frequency division multiplexing with block-wise index modulation (MM-OFDM-BIM) has been proposed as a novel OFDM-IM technique with adjustable-reliability transmission and low detection complexity. Although the phase normalization for PSK can reduce the complexity of the index modulation (IM) detection, the essence of constant symbol power of PSK limits its bit error rate (BER) performance. We propose a new constellation design to reallocate the original symbols into two-level power for PSK-based MM-OFDM-BIM while retaining the merit of phase normalization. By adopting the optimum power parameter, the numerical results demonstrate that the proposed scheme can effectively improve BER performance without increasing computational complexity.