Rate Enhancing Superposition Coding Scheme for Two-Way Relaying

摘要

Recent advances in cooperative communication and wireless Network Coding (NC) may lead to huge performance gains in wireless relay systems. In this context, we focus on the two-way relay scenario, where two nodes exchange information via a common relay. We design a Superposition Coding (SC) based NC scheme for De-code-and-Forward (DF) half-duplex relaying, where the goal is to increase the achievable rate. By taking advantage of the direct link and by providing a suboptimal yet efficient power division among the superposed layers, we show that our proposed SC two-way relaying scheme outperforms the reference schemes, including the well-known 3-step DF-NC scheme, while approaching extremely closely the performance upper-bound.