Generalized multiplicative network coding for the broadcast phase of bidirectional relaying

A generalization of symbol-level multiplicative network coding is presented in this paper. The effects of non-constant amplitude modulation on the error probability of bidirectional relaying links are investigated analytically and through computer simulations. A constellation rearrangement is then presented to further enhance the performance. Simulation results show that the proposed method is able to alleviate the link asymmetry problem in bidirectional relaying and provide considerable throughput gains compared to equally simple network coding techniques.