Joint utility optimization resource allocation scheme for cognitive relay networks

In a cognitive relay network (CRN) consisting of multiple pairs of PUs and CUs, the resource allocation issues, specifically, the spectrum and power allocation and relay selection for secondary users (SUs) have to be considered to support efficient spectrum sharing among primary users (PUs) and SUs and providing quality of service (QoS) guarantees for both PUs and SUs. In this paper, we address the issue of resource allocation in CRNs and formulate the utility of all SUs as a function of node transmission mode, transmission power and subchannel allocation strategy and relay selection scheme. Through maximizing the utility function subject to multiple resource allocation constraints, the optimal transmission mode, relay selection, transmission power and subchannel allocation strategy is obtained. Simulation results demonstrate that proposed scheme enables joint performance optimization of SUs and outperforms previously proposed schemes.