Power control for buffer limited physical layer network coding

The requirement of high data rate and energy efficiency for a new generation of wireless network should reshape the designs of wireless heterogeneous network architecture including wireless relaying. For two-top bi-directional information exchange in wireless networks, we consider a wireless transmission design, which adopts the bi-directional relaying channel and the physical broadcasting. The bi-directional relaying channel is roughly divided into Decode and Forward (DF) strategy and Amplify and Forward (AF) strategy. This work focuses on a power control scheme of the DF-based bi-directional relaying in the configuration of a limited and a non-limited buffer. This scheme assumes that the transmitters of two source nodes have the channel gain information of the bi-directional relaying channel. The numerical results show that: the size of buffer at the relay node will not affect average end-to-end capacity over the Rayleigh fading channel while the size of maximum buffer is set as to an appropriate value. In addition, optimal power control will significantly improve the average end-to-end capacity of the transmission strategy compared to that of the equal power control scheme.