On the Performance of New Spatial Modulation Scheme for Frequency Selective Channels

OTFS has been recently proposed to achieve time and frequency diversities, especially in linear time-variant (LTV) channels with large Doppler frequencies. The idea is based on the precoding of the data symbols using symplectic finite Fourier transform (SFFT) then splitting the frequency selective channel into flat components via OFDM waveform. Implementing OTFS technique when the number of transmit/receive antennas increases may become very fast computationally prohibiting, because of the augmented number of RF chains and the one of OFDM subcarrier branches per RF chain. One promising solution to such issue in the context of massive MIMO is the spatial modulation (SM) technique, which only activates a single transmit antenna in any symbol-interval, thereby necessitating a sole RF chain. In this paper, we propose to incorporate OTFS signaling into SM architecture and evaluate the attained data reliability. Simulation results show that OTFS-based solution outperforms the recently presented SM-OFDM alternative.