Generalized spatial modulation with transmit antenna grouping for massive MIMO

In this paper, an effective low complexity generalized spatial modulation (GenSM) scheme with transmit antenna grouping is proposed for massive multi-input multi-output (MIMO) system to deal with the channel correlation among transmit antennas. In the proposed scheme, all transmit antennas are divided into several equal-sized groups, and spatial modulation (SM) is carried out to select one active antenna in each group independently. Two different grouping methods, i.e., block grouping and interleaved grouping, are introduced to optimize the error performance in low and high signal-to-noise ratio (SNR) region, respectively. In consideration of the large amount of transmit antennas in a massive MIMO system, both linear and 2-dimensional transmit antenna arrays are considered in our design. To evaluate the performance, a closed-form expression of the average bit error probability (ABEP) upper bound is derived for all proposed grouping methods and Monte-Carlo simulations are conducted to verify the analysis and reveal the performance gain of the proposed scheme in terms of bit error rate (BER) in comparison with conventional GenSM.