I/Q imbalance and loop-back self interference effects in full-duplex OFDM DF relays

We analyze the outage probability of dual-hop full-duplex decode-and-forward relaying for an orthogonal frequency division multiplexing system in the presence of I/Q imbalance. We derive accurate analytical approximations which quantify the outage probability's functional dependence on the I/Q imbalance level and the residual loopback self-interference average power level. In addition, we derive the condition at which direct transmission outperforms full-duplex decode-and-forward relay-assisted transmission in the presence of I/Q imbalance. Furthermore, we propose an opportunistic relaying approach and demonstrate its robustness against the detrimental effects of I/Q imbalance and residual loopback self-interference. Our numerical results confirm the accuracy of our analysis.