Spectrum Sensing is an essential part of Cognitive Radio. Spectrum can be sensed by numerous algorithms. Energy Based can easily detect presence of signal and cyclostationary based detection can easily detect signals at low SNR. We havecollaborated the two algorithms resulting in a Collaborative Approach. In addition to that a feature based detection has been used for calculating the probability of missed detection of TV signals at low SNR. In this paper we have sensed the TV signals as well as the probability of missed detection for both are calculated. Collaborative approach efficiently detects the TV signals utilizing the concept of threshold energy and differentiating noise form original signal. Feature detection calculates on the basis of extraction of spectral features of TV signals. Simulation results show that the proposed sensing technique can reliably detect analog and digital TV signals at low SNR.

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Spectrum Sensing Congnitive Radio Missed Detection Feature Detection.