Selective decode-and-forward two-way relay network with weighted decision-feedback differential coherent detectors

This paper considers a selective detect-and-forward two-way relay network employing differential MPSK modulation with Weighted Decision-Feedback Differential Coherent (W-DFDC) receivers. The system employs a three-phase relaying protocol with direct transmissions, where two terminals transmit separately in the first two phases. In the third phase, the relay forwards the network coded message to both terminals only if it has successfully decoded both messages received from the terminals. At the destination nodes, SNR-dependent thresholds are proposed to allow only the received signal from the relay corresponding to when it transmits to be combined with the signal from the direct link. Monte Carlo simulation results for fast fading channels show the performance gains of this relaying scheme with W-DFDC receivers over conventional differential detectors.