• Network coding
• Physical Layer Network Coding
• Convolutional Code

I study the application of trellis codes to physical layer network coding in relay communications, with two, three or four users. In particular, I consider non-binary 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. I focus on the multiple-access phase, in which the terminals transmit their messages simultaneously, while in the second phase the relay will retransmit the network-coded combination of every messages. I also evaluate the performance of both options for the decoding of the individual message of each terminal.