GLRT Based Active Spectrum Sensing for Cognitive Radio Systems

In this paper, we have proposed an active spectrum sensing method which benefits from primary user's closed loop power control. The idea of active sensing let the cognitive transmitter to use the spectrum by estimating the maximum power of cognitive Radio transmitter that doesn't lead to harmful interference to primary receiver in the range of primary transmitter. So a cognitive radio can communicate through spatial holes of spectrum. Our work is based on generalized likelihood ratio test (GLRT) model. Using a probabilistic modeling of power profile of primary transmitter and employing energy detection as a channel measurement metric for power statistics, we have developed a GLRT based decision metric for spectrum decision process.