A Novel Low-Complex Antenna Selection Scheme for Beyond 4G (B4G) Systems

Abstract

Multi input multi output (MIMO) based transmission modes are very popular in 4G and beyond wireless standards. It offers high quality services at the cost of increased hardware and signal processing complexity. Antenna selection is one of the suitable solutions to overcome the limitations of MIMO scheme. Antenna selection schemes are becoming very popular in the recent wireless techniques like massive MIMO, cognitive radio, multi-hop relay networks (MHR) and wireless local area networks. Instead of using all the available antennas for transmission and reception, antenna selection schemes select good antennas based on the channel state information (CSI). To attain the full benefits of transmitter and joint antenna selection schemes, accurate CSI is required at the transmitter side. The non-zero feedback delay and time varying channel conditions, make the CSI available at the transmitter outdated, which also affects the antenna selection process. In this work, we have derived the closed form average symbol error rate (SER) expression of M-ary phase shift keying (PSK) modulation, for three different antenna selection schemes, by considering the effect of delayed CSI. All these derived expressions are the function of correlation between CSI at the receiver and delayed CSI at the transmitter. The simulation results show that the antenna selection gain decreases with the decrease in correlation. It is also observed that scheme 1 based antenna selection is optimal under delayed CSI conditions, for different constellations and more suited for future wireless standards.