Asymptotic capacity of the separated MIMO two-way relay channel with linear precoding

A multiple-input multiple-output two-way relay channel consisting of two communication nodes and a full-duplex relay node is considered, assuming that no direct link exists between the two communication nodes. We propose an achievable scheme using lattice codes combined with generalized singular value decomposition-based precoding for the first phase and vertically encoded structural bining for the second phase. We show that the proposed scheme achieves the cut-set bound asymptotically as the signal-to-noise ratio tends to infinity.