Decisive Factors and Impacts of False Detection in Spectrum Sensing in Cognitive Radio

Abstract

The increasing demand for wireless communication introduces efficient spectrum utilization challenges. Cognitive radio has emerged as the key technology to address this challenge which enables opportunistic access to the spectrum. The main potential advantages introduced by cognitive radio are improving spectrum utilization and increasing communication quality. Cooperative spectrum sensing improves the probability of detection by collaborating to detect primary user's signal in cognitive radio (CR) system as well. The goal of this thesis is to cooperate the cognitive users to increase the detection probability for a given probability of false alarm and find out the better condition of sensing spectrum among three rules: AND, Majority, OR. Here, we propose a cooperative spectrum sensing and signal detection in the CR system by implementing AND rule, Majority rule and OR rule under the AWGN channel and fading channel. To find out better detection, here we compare between AND, Majority, and OR rules. It is observed that the probability of detection for a given value of probability for the false alarm has been significantly achieved by optimal value of detection probability in AND rule, Majority rule, OR rules as the number of the user increases. Finally we also see the effects of fading over the spectrum sensing. We have observed that due to fading condition, the amplitude of signal deviates. In fading condition AND rule gives better performance in detection probability among three rules.