PERFORMANCE COMPARISION OF EIGEN VALUE BASED SPECTRUM SENSING FOR DIFFERENT MODULATION SCHEMES

Abstract

Recently wireless system have been growing very fast. To meet this huge growth in wireless technologies and services, researchers as well as industry have been working towards new techniques and standardizations. The most critical consequences for this growth in wireless networks are the ones related to spectrum usage and management as the electromagnetic radio spectrum is as the most precious Natural resource when there is discussion about wireless networks. The existing policies of spectrum management are based on static spectrum allocation for a specific technology and service controlled by regulation agencies like the Federal Communications Commission (FCC) And the European Telecommunications Standards Institute (ETSI). After the appearance of wireless personal communications technologies it became unreasonable to use these policies and rely on static spectrum allocation due to economic and technical considerations. Cognitive radio Technology was introduced to mitigate fixed spectrum allocation problem. Cognitive radio is a radio that adapts to the conditions of the environment by analysing, observing and learning. The cognitive network makes use of these adaptations for future decisions. Cognitive radio is basically used for maximum utilization of the radio bandwidth. The core of the performance Accurate detection of available spectrum is the main problem in cognitive radio. Performance of cognitive radio mainly depends on its detection accuracy. A cognitive radio should detect any type of radio signal available to its radio environment. In this project a survey detection probability for different modulation schemes has been presented. A cognitive radio should have fast processing speed and able to take fast decision. For that its design structure should be less complex. So for that purpose, improvement on existing Eigen value based spectrum sensing is also presented and probability of detection are calculated for TV band and mobile communication band communication.