Performance analysis of OFDM based 3-hop AF relaying network over mixed Rician/Rayleigh fading channels

In this paper, performance of an orthogonal frequency division multiplexing (OFDM) based 3-hop variable-gain amplify and forward (AF) relaying network is analyzed over independent and non-identically distributed (i.n.i.d.) mixed Rician/Rayleigh fading environment. Analytical expression of outage probability is derived and diversity order of the considered system is found. Further, average symbol error rate (ASER) expressions of general order hexagonal quadrature amplitude modulation (HQAM), general order rectangular QAM (RQAM) and 32-XQAM are derived. A comparative analysis of ASER for different QAM schemes with different constellations is also presented. Ergodic capacity with optimum rate adaptation is also derived for the considered system model. Further, the impact of Rician K-factor on the performance of the considered system is highlighted. Finally, the derived analytical results are verified through Monte-Carlo simulations for different signal-to-noise ratio (SNR) levels.