We study the application of trellis codes to physical-layer network coding in the two-way relay channel. In particular, we consider quaternary decoding on a combined trellis as an alternative to binary decoding and evaluate its gain in several scenarios, including asymmetric channels and the combination of different codes. We focus on the multiple-access phase, in which both terminals transmit their messages simultaneously, while in the second phase the relay retransmits the network-coded combination of both messages. We also evaluate the performance of both options when decoding the individual message of each terminal.

keywords: {network coding;trellis codes;asymmetric channels;multiple-access phase;network-coded combination;physical-layer network coding;quaternary decoding;trellis codes;two-way relay channel;Convolutional codes;Fading;Maximum likelihood decoding;Network coding;Relays;Wireless communication;Physical-layer network coding;convolutional codes;non-binary decoding}

File: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6612076&isnumber=6611995