Sensing user selection based on energy constraints in cognitive radio networks

In cognitive radio networks (CRNs) unlicensed Secondary Users (SU) are allowed to access the resources of licensed Primary Users (PU), if they do not make harmful interference to them. In Cooperative Spectrum Sensing (CSS), SUs sense the spectrum independently and send their sensing information to a fusion center combining the received information and making the final decision about the PU presence. The reliability of decision that FC makes is improved by CSS. However, the various requirements of SUs such as battery constraints are not usually considered during CSS process. Therefore, in this paper an energy based user selection algorithm is proposed in which the participants in CSS are selected based on their energy constraints. Our proposed algorithm prevents from early finishing the battery life of SUs by balanced distribution of sensing process among all of them. Numerical results confirm the improved performance of the proposed algorithm in comparison with conventional ones.