Codebook Design for OFDM with In-phase/Quadrature All Index Modulation

In this paper, we present a codebook design for OFDM with all index modulation (OFDM-AIM). The OFDM-AIM scheme encodes all the messages with index bit mapping, which delivers better diversity gain than the conventional index modulation. The error probability of the scheme in terms of Hamming distance and Euclidean distance of the codebook is devised. We show that the Hamming distance of codebook affect the diversity gain of error probability directly and we have developed a design procedure to build the codebook with different minimum Hamming distance requirements. We have also reworked the complex OFDM-AIM into two real index modulations on the in-phase and the quadrature channels called OFDM with in-phase/quadrature all index modulation (OFDMI/Q-AIM), which further improves the spectral efficiency. Both the theoretical and simulation results show that the proposed codebooks for the OFDM-AIM and the OFDM-I/Q-AIM outperform prior arts of index modulated OFDM schemes in diversity gain over frequency-selective Rayleigh fading channel.