New Optimal Power Allocation for Bidirectional Communications in Cognitive Relay Network Using Analog Network Coding

Cognitive radio and cooperative communication can greatly improve the spectrum efficiency in wireless communications.We study a cognitive radio network where two secondary source terminals exchange their information with the assistance of a relay node under interference power constraints.In order to...Cognitive radio and cooperative communication can greatly improve the spectrum efficiency in wireless communications. We study a cognitive radio network where two secondary source terminals exchange their information with the assistance of a relay node under interference power constraints. In order to enhance the transmit rate and maintain fairness between two source terminals, a practical 2-phase analog network coding protocol is adopted and its optimal power allocation algorithm is proposed. Numerical results verify the superiority of the proposed algorithm over the conventional direct transmission protocol and 4-phase amplify-and-forward relay protocol.SCI(E)04144-148