Springer Science+Business Media
In this paper, the authors study the Gaussian Two-Way Relay Channel (GTWRC), where two nodes exchange their messages with the help of a half-duplex relay. The authors investigate a cooperative transmission protocol, consisting of four phases: Multiple Accesses (MA) phase, broadcast phase and two cooperative phases. For this setup, they propose a new transmission scheme based on superposition coding for nested lattice codes, random coding and jointly typical decoding. This scheme divides the message of each node into two parts, referred to as satellite code word and cloud center. Depending on the phase type, the encoder sends a linear combination of satellite code words or cloud centers. For comparison, a rate region outer bound using a cut-set bound is provided.