Performance analysis of two‐way AF relaying system with the presence of hardware impairments over Nakagami‐ m fading channels

Abstract

The authors evaluate theoutage probability, ergodic capacity, and symbol error rate (SER) performances of an amplify-and-forward relaying system equipped with a non-ideal variable gain single relay with hardware (HW) distortions at both the transmitter and receiver sides with the derivations of the instantaneous end-to-end signal-to-noise-and-distortion ratios. More specifically, they analytically derive new algebraic expressions for the outage probability and ergodic capacity in the two-way relaying system over the Nakagami-m fading environments. They further derive new closed-form expressions for the asymptotic outage probability to analyse the performance in the high signal-to-noise regime. The derived statistics, along with the transmitter–relay–receiver channels are then used to obtain a closed-form expression of the approximate and upper bound ergodic capacity. Finally, they investigate the generic mathematical expressions utilising the average and asymptotic SER, valid for several types of modulation schemes operating over the Nakagami-m fading. Monte Carlo simulations and numerical examples are provided to quantify the validity of the derived analytical expressions. The authors' results highlight the effect of HW impairments in the two-way relaying system over the Nakagami-m fading channels and reveal the impact of the level of HW impairments, data rates, modulation types, and shaping parameters on the overall system performance.