Spatial modulation for OFDM with linear constellation precoding

Direct application of spatial modulation (SM) for orthogonal frequency division multiplexing (OFDM) systems does not realize the inherent frequency diversity gain since information symbols are not spread over independently-faded subcarriers. This paper investigates a new transmission scheme that employs spatial modulation (SM) for each group of subcarriers in OFDM. Specifically, OFDM symbols in each group are passed through a precoder to maximize the diversity and coding gains, while spatial modulation is applied in each group to convey more information bits by antenna indices. Performance analysis and simulation results are carried out to demonstrate the superiority of the proposed scheme over a previously-proposed combination of SM and OFDM.