Link-oriented power allocation in multicast systems with physical layer network coding

Maximizing system sum-rate or minimizing error rate with constrained power are the main research focuses in the previous system-oriented power allocation schemes. However, link-oriented power allocation schemes that minimize power consumption with constrained rates for every link, attracted researchers in recent energy efficiency system design. In this paper, a link-oriented optimal power allocation scheme is firstly proposed for physical layer network coding with DeNoise-and-Forward protocol in multicast system, that two sources and two destinations communicating with the assistance of arbitrary number of relays. We also consider a suboptimal power allocation scheme with low complexity, where a single relay is chosen to minimize the power consumption. The numerical simulation shows that the suboptimal power allocation scheme also can achieve relatively low power consumption, even approach to the optimal scheme in some special case.