Spectrum Sensing Methods for DTMB Based Cognitive Radio Systems

Cognitive Radio (CR) systems are well considered to be used in television bands as IEEE 802.22 WRAN suggested. And as Digital Television Terrestrial Multimedia Broadcast (DTMB) is the standard for China digital television which has been implemented since Aug. 1st 2007, two simple and efficient spectrum sensing methods for DTMB based CR systems are proposed in this paper. The proposed methods are based on the PN sequences of DTMB frame header. Both methods have a property of little time-delay. The performances of the methods are studied by simulations. Simulation results show that both methods have good performances when SNR is not too low.