Time divisional and time-frequency divisional cooperative spectrum sensing

In this paper we present a time divisional and a time-frequency divisional cooperative spectrum sensing technique suitable for cognitive radio (CR) networks. The two methods are well suited for very high bandwidth CR networks, such as UWB networks, where the individual nodes need to scan a wide range of spectrum which is a time consuming process. With the time divisional and the time-frequency divisional cooperative spectrum sensing approaches the nodes share the spectrum sensing functions cooperatively, coordinating in time and frequency, covering the total frequency band and also in near-continuous time. In this paper we present the corresponding algorithms and techniques for the two cooperative spectrum sensing approaches, analyze their performances, and compare the advantages and disadvantages with each other. We also present simulation results to verify the performance improvements in terms of probability of miss detection and the probability of false alarm for detecting the PU. Results show that the the proposed methods are best suited for detecting the PUs having low spectral occupancy statistics who occupy the spectrum very seldom.