An anti-interference spectrum sharing protocol with secondary user selection

In this paper, we proposed an anti-interference cooperation spectrum sharing protocol with secondary user selection. Specifically, one secondary user is selected to assist the primary system to achieve the target rate by acting as a decode-and-forward (DF) relay, which uses a fraction of time and bandwidth to forward the primary signal. As a reward, the selected secondary user can gain spectrum access by using the remaining bandwidth to transmit its own signal. The secondary system use different bandwidth to transmit the primary and its own signal, thus there will be no interference exists between the primary and secondary systems. We study the joint optimization of time and bandwidth as well as secondary user selection such that the secondary transmission rate is maximized, while the primary system can achieve its target rate. Simulation results demonstrate that both primary and secondary systems benefit from the proposed spectrum sharing protocol.