Outage Analysis of OFDM Based AF Cooperative Systems in Selection Combining Receiver over Nakagami-m Fading Channels with Nonlinear Power Amplifier

In this paper, we investigate the performance of orthogonal frequency division multiplexing (OFDM) based amplify-and-forward (AF) cooperative relaying systems over independent and identically distributed (i.i.d) Nakagami-m fading channels. Specifically, we derive a closed-form expression for lower bound of outage probability by using selection combining (SC) scheme at the receiver. A nonlinear power amplifier (PA) is considered at the relay which introduces the nonlinear distortions. We present simulation and numerical results to validate the theoretical analysis, and demonstrates the impact of nonlinearity of PA parameters over outage probability for different values of threshold signal-to-noise ratio (SNR) at various mean SNR levels