Performance analysis of Group based Cooperative Sensing Schemes

With the growing demand for wireless applications, there is an incalculable rise in bandwidth consumption that in turn leads to the spectrum scarcity. The conflict between spectrum underutilization and spectrum scarcity is solved by a well-known technology called Cognitive Radio (CR). The main aim of CR is to exploit unutilized spectrum of licensed users/Primary Users (PUs) and enable opportunistic communications for unlicensed users/Secondary Users (SUs). CR communications need a primary technique called Spectrum Sensing which enables the CR users to accustom to their environment by finding frequency bands of PU that are idle (Spectrum Holes-SHs). There is a need to develop a technique that increases the accuracy of sensing not at the cost of sensing efficiency, as majority of the existing cooperative sensing schemes do not pose the benefit of cooperation. Our proposed work presents a Group based Cooperative Sensing Scheme (GCSS) to make a balance between accuracy and efficiency of sensing. An analytical model has been developed in both time-invariant and time-variant channel conditions using which sensing parameters like efficiency and accuracy are analyzed. An optimization scheme to achieve maximum throughput is developed. Extensive simulations demonstrate that GCSS outperforms as compared to the other existing schemes.