Find in Library

A wireless network scenario of bidirectional relaying with imperfect channel side information (CSI) is considered, in which two source nodes intend to exchange information with the help of one relay. The power allocation problem is investigated to minimize the total transmit power subject to constraints on two source nodes' received signal-to-noise-ratios (SNRs). The best relay that minimizes the total transmit power is selected in a multiple relay network. We also present outage analysis when the proposed power allocation is adopted, and a close-form approximation of outage probability is obtained by shrinking the integral interval. Simulation results show that the total transmit power can be substantially decreased and the outage probability is significantly decreased by the proposed power allocation scheme when two source nodes have different QoS requirement.