On the ergodic capacity of MIMO-NOMA systems with JTRAS protocol under imperfect SIC and CSI

Abstract

ABSTRACT Antenna selection serves as an effective way of reducing complexity when dealing with multiple antennas, allowing for better signal transmission from a reduced number of antennas and thus increased system performance. In this paper, we derive a closed-form expression for the ergodic capacity (EC) of a multi-input multi-output non-orthogonal multiple access (MIMO-NOMA) network utilising joint transmit and receive antenna selection (JTRAS). We analyse the two-user and multi-user scenarios over Rayleigh fading channels with both imperfections: successful interference cancellation (SIC) and channel state information (CSI). To illustrate the gains of our proposed system, we compare its performance to that of its perfect counterpart. We observe that SIC and CSI imperfections have a significant impact on the performance of MIMO-NOMA networks. Furthermore, applying JTRAS to MIMO-NOMA also yields a higher sum EC than MIMO orthogonal multiple access (MIMO-OMA) with JTRAS. Finally, the close agreement between the analytical, asymptotic and simulation results validates the presented analysis.