A pilot-aided detector for spectrum sensing of Digital Video Broadcasting-Terrestrial signals in cognitive radio networks

摘要

In this paper, the main properties of digital television broadcasting signals based on the Digital Video Broadcasting-Terrestrial (DVB-T) standard are analyzed, and these properties are utilized to design a new pilot-aided detector for spectrum sensing in cognitive radio networks. The proposed detector consists of a processing unit and a combination and decision unit. In the processing unit, multiple statistics that correspond to different enhanced pilot components are computed. In the combination and decision unit, three newly proposed combination schemes are adopted to combine these statistics, and then, a final decision on the presence or absence of the DVB-T signals is made on the basis of the Neyman-Pearson criterion. The proposed pilot-aided detector exploits both the periodic continual and scattered pilots that are intrinsic in the DVB-T signals, processes the observed data timely, experiences short sensing duration, and requires no time synchronization information. Furthermore, the proposed pilot-aided detector is able to distinguish DVB-T signals from interference. Theoretical analysis and simulation results show that spectrum bands that are not currently occupied by the DVB-T systems can be detected accurately by using the proposed pilot-aided detector. Simulation results also demonstrate the significant performance gain of the proposed detector compared with the counterparts.