Spectral efficient cooperative relaying techniques via Physical Network Coding

In order to avoid the loss of spectral efficiency (throughput) caused by half-duplex mode and further improve achievable throughput performance of wireless multi-hop network, a relaying technique that utilizes two sets of relays and physical network coding over bi-directional traffic flows is introduced. We term such technique as Bi-directional Successive Relaying based on Physical Network Coding (PNC-BSR). The whole scheme is based upon two key elements: a) To combat the half-duplex constraint by having two cooperative relays transmitting alternatively at every hop, i.e., the one receiving while the other transmitting and vice versa, and b) to enhance the throughput performance using physical network coding at relay nodes. Numerical results show that at high signal-to-noise ratio (SNR) regime, PNC-BSR offers a superior throughput performance.