Automatic Modulation Recognition in Two- Way Relaying Channel with the Presence of Relay Transceiver Hardware Impairments

Abstract

Modulation recognition (MR) is well-known as one of the enabling tools, which aims to further afford efficient and secure communications in cognitive radio (CR) context for 5G and beyond networks. In this Paper, we propose a robust MR approach designed for two-way MIMO cooperative relaying network by specifically taking into account two crucial constraints: hardware impairments at relay transceiver and co-channel interference. To mitigate the effect of these impairments, feature-based artificial neural network (ANN) recognizer combined with a nonlinear design of the relay processing matrix with dirty paper coding (DPC) is investigated in this work. Simulations using two receive criterions, namely DPC-ZF and DPC-MMSE, have been carried out to validate the effectiveness of the proposed approach. It has been proved that both DPC-ZF and DPC-MMSE provide high modulation recognition, whatever the impairments level at the relay transceiver.