Performance Analysis of Full-Duplex AF Relaying with Transceiver Hardware Impairments

G. GONZÁLEZ; T. RIIHONEN; J. E. COUSSEAU; F. GREGORIO; R. WICHMAN

Oulu

Conferencia; 22th European Wireless Conference; 2016

University of Oulu

We propose a joint widely-linear I/Q imbalancecompensation and self-interference (SI) cancellation scheme foramplify-and-forward (AF) full-duplex (FD) relay transceivers.Furthermore, we study the bit-error rate (BER) performanceof a complete two-hop link considering hardware imperfectionsin transceiver electronics. Especially, if the relay gain increases,the signal-to-noise ratio (SNR) at the destination becomes higherbut this also increases the SI level due to the FD operationand, as a consequence, the signal-to-interference-plus-noise ratio(SINR) at the relay input decreases. To settle this trade-off, wefind numerically the optimal input back-off (IBO) for the relaypower amplifier (PA) maximizing the BER at the destination.Simulations show that the optimal IBO depends on the targetedBER level and the PA nonlinearity. The numerical resultsshow also that the distortion from the PA dominates the otherhardware impairments at high SNR. Finally, we show that theproposed cancellation scheme can completely eliminate the I/Qimbalance, even with mixers that have low image rejection ratio(IRR).