Approach of Robust Resource Allocation in Cognitive Radio Network With Spectrum Leasing

In this paper, the spectrum leasing mode is adopted as a promising approach to fully use spectrum resource in Cognitive Radio Networks (CRNs). In CRNs, Primary Transmitter (PT) can fulfill agreement with Secondary Users (SUs) that PT leases part of licensed spectrum to SUs in order to exchange additional transmission from SUs. We focus on the optimal resource allocation in CRNs satisfying the requirements both of PT and SUs. Correspondingly, we propose a resource optimization model with consideration of uncertainty of channel gain, which attempts to reduce the energy consumption of PT on the premise of guaranteeing the Quality of Service (QoS) and improve the adaptiveness to the uncertain communication environment. In the meantime, the information transmission of the SUs can be ensured. When the communication outage probability caused by the channel gain uncertainty is considered, a probability constrained robust optimization resource allocation algorithm is proposed to obtain the optimal solutions. Numerical results show that the proposed algorithm is effective in saving the energy of PT and satisfying the robustness requirements. The results also show the system performance achieved by the proposed algorithm is better than that of some other existing algorithms.