OFDMA/SC-FDMA aided space-time shift keying for dispersive multi-user scenarios

Abstract

Motivated by the recent concept of Space-Time Shift Keying (STSK) developed for achieving a flexible diversity versus multiplexing gain trade-off, we propose a novel Orthogonal Frequency Division Multiple Access (OFDMA)/Single Carrier Frequency Division Multiple Access (SC-FDMA) aided multi-user STSK scheme for frequency-selective channels. The proposed OFDMA/SC-FDMA STSK scheme is capable of providing an improved performance in dispersive channels, while supporting multiple users in a multiple antenna aided wireless system. Furthermore, the scheme has the inherent potential of benefitting from the low-complexity single-stream Maximum-likelihood (ML) detector. Both an uncoded and a sophisticated near-capacity coded OFDMA/SC-FDMA STSK scheme were studied and their performances were compared in multiuser wideband Multiple-Input Multiple-Output (MIMO) scenarios. Explicitly, OFDMA/SC-FDMA aided STSK exhibits an excellent performance even in the presence of channel impairments due to the frequency-selectivity of wideband channels and proves to be a beneficial choice for high capacity multi-user MIMO systems