Spatial correlation based analysis of soft combination and user selection algorithm for cooperative spectrum sensing

This study presents an analytical method that shows how spatial correlation degrades the overall performance of cooperative spectrum sensing. In a cooperative spectrum sensing, where all secondary users (SUs) report their sensing information to the fusion centre (FC), sensing information is correlated for closely located users due to the similar surrounding environment. Considering the soft combining at the FC, this study shows how detection performance of correlated SUs is different from uncorrelated SUs. Furthermore, an algorithm is proposed which selects best uncorrelated SUs among all SUs of the network based on received power to the FC from SUs. The simulation results confirm the performance analysis of cooperative spectrum sensing with spatial correlation on the sensing data.