Transceiver Design for Hybrid One-Way and Two-Way Relay Networks

Due to a variety of service types required by different users, unidirectional and bidirectional data transmissions may coexist in a relay network. In this letter, we consider such a hybrid one-way and two-way relay network, where both unidirectional and bidirectional data transmissions are delivered simultaneously between different user pairs via a common multi-antenna relay node. We first develop a relaying scheme that provides inter-pair interference free transmissions for all users. A near optimal power allocation method at the relay is then proposed to maximize the system sum rate. Numerical results show that our relaying scheme significantly outperforms the traditional zero-forcing based scheme.