A novel sensing nodes selection scheme for energy efficiency of cooperative spectrum sensing in cluster-based CRSNs

Applying cognitive radio technologies to wireless sensor networks (WSNs) explores new possibilities for network architectures. The cognitive radio technology enables opportunistic access of unlicensed sensor nodes to licensed bands without influencing primary users (PUs). Spectrum sensing is a key technology to identify the presence of PUs. Benefit from the diversity of different sensors, Cooperative spectrum sensing (CSS) can provide a more reliable sensing result compared with individual spectrum sensing. However, due to limited energy of batteries in cognitive radio sensor networks (CRSNs), more energy consumed by CSS will result in a short network lifetime. In this paper, a novel sensing nodes selection scheme is proposed to improve energy efficiency of cooperative spectrum sensing for cluster-based CRSNs. A novel optimization technique is employed to optimize the number of spectrum sensing nodes in a cluster. The optimized results can efficiently maximize the detection probability and minimize false alarm probability. In addition to this, the proposed scheme can efficiently balance the energy consumption among different sensors to some extent. Through a set of simulation, it is verified that the proposed scheme can obtain a good sensing performance with less sensor nodes and energy consumption, and thus, prolong the network lifetime.