On the optimum power allocation in the one-side interference channel with relay

The optimum power allocation of the one-side interference channel with the non-cognitive relay node was studied. Assuming the orthogonal resources were used on the channels between the sources and relay node, we first derived a transmission scheme based on the dirty paper coding and the interference cancellation. Then with this transmission scheme the rates that was achievable in both the weak and strong interference regimes were given. A joint power allocation scheme among the sources and relay node was proposed, which maximized the sum-rate. The performance of the proposed power allocation scheme was proved. More explicit analysis investigated the effects of the noncognitive feature of the relay node on the power allocation and sum-rate. The relationship between the channel gains and the optimum joint power allocation had also been analyzed.