Beijing University of Posts and Telecommunications
With the rapid development of wireless communication networks, more and more spectrum resources are required and the scarcity in spectrum has become a serious concern. Cognitive Radio (CR) technology, which enables Secondary User (SU) to access the idle frequency bands known as the spectrum hole, has been proposed to improve the current severely underutilized spectrum. However, due to imperfect channel condition, i.e. shadowing, high penetration loss or multipath fading, it is difficult for a SU to obtain fast and accurate sensing result by implementing spectrum sensing alone. To overcome this drawback, cooperative spectrum sensing, which makes multiple Secondary Users (SUs) conduct spectrum sensing cooperatively, is proposed to improve sensing performance.