Adaptive three-phase differential transmission scheme for two-way relay networks

This work considers two-way relay network (TWRN), where two source nodes transmit information bits to each other with the help of a relay node. To avoid channel estimation at the receiver and perfect synchronization, we propose adaptive three-phase differential transmission schemes for the TWRN where the relay node re-encodes its sending signals according to its detection status in the first and second phase dynamically. Numerical results show that the proposed optimal adaptive differential transmission schemes outperform the conventional two-phase protocol significantly in the high signal-to-noise ratio region. To further decrease the computation complexity, a sub-optimal combination scheme is proposed and proved to be as effective as optimal combination scheme to enhance system robustness. © 2016 Journal of Communications.