Performance degradation of Turbo Coded Physical Layer Network Coding on the Two-Way Relay Channel

This paper investigates the performance degradation of Hierarchical Decode-and-Forward (HDF) Turbo Coded Physical Layer Network Coding (PLNC) on the Two-Way Relay Channel (TWRC) compared to a single user end-to-end Turbo coded system, which provides a simple upper bound on the performance. We have analyzed the basis of this degradation by both Information Theory and numerical derivation, also using EXIT charts. This results in a tighter performance bound, and shows that the degradation inherently results from the superposition of the electromagnetic signals.