Multi-pair full-duplex amplify-and-forward relaying with very large antenna arrays

This paper considers the multi-pair full-duplex massive MIMO relaying, where multiple source-destination pairs communicate simultaneously with a common full-duplex amplify-and-forward relay. The low-complexity transceiver design at the relay based on zero-forcing (ZF) processing is presented. The asymptotic expression of the end-to-end signal-to-interference-plus-noise power (SINR) is derived under the general power scaling scheme. Through the theoretical results, we show that the deployment of very large antenna arrays at the relay has potential to eliminate the effect of echo interference due to the full-duplex operation, if the power scaling scheme is properly selected. Moreover, it is shown that the multi-pair full-duplex relaying outperforms the multi-pair half-duplex relaying in the spectral and energy efficiencies when the number of relay receive/transmit antennas is large.