A Novel Multi-user Spatial Modulation-based Code Division Multiple Access Scheme

Abstract

Multiple-antenna techniques constitute a key technology for modern wireless communications, which establishes a trade-off between the data reliability and the data rate, and which may result in an increased system complexity and cost. Among the many transmission architectures which exploit multiple-antenna at either the transmitter, the receiver, or both, spatial modulation (SM) is a novel and recently proposed multiple-antennas transmission technique which can offer, with a very low system complexity, improved data rates compared to Single Input Single Output (SISO) systems, and robust error performance even in correlated channel environments. This is achieved by adopting a simple but effective coding mechanism that sets a one-to-one mapping between blocks of information bits to be transmitted and the spatial positions of the active antenna in the antenna array. The main goal of this work is to analyse the viability of spatial modulation as a technology to implement and support future 5G systems that are currently being developed. Since these systems will be deployed in frequency selective channels resulting from the targeted high data rates, and in the presence of multiple users, techniques such as orthogonal frequency division multiplexing (OFDM) and code division multiple access (CDMA) may be involved. Hence, our objective is to investigate the performance of SM-CDMA and SM-OFDM-CDMA architectures in such frequency selective channels.