Performance Analysis of Cooperative Spectrum Sensing under Urban Environments

In cognitive radio networks, cooperative spectrum sensing is employed to detect the presence of primary user quickly and accurately. In this paper, we derive a novel numerical model for the scheme of cooperative sensing based on cooperative relay, and study the impacts of different parameters on the improvement of spectrum sensing performance under urban environments, while there is power constrain for relay user. The ratio of environment factor between the channel from primary user to cognitive user (lambda(1)) and the channel from cognitive user to cognitive user (lambda(2)) angle phi between the primary user and two cognitive users are considered. Numerical results show that, under the urban environment, the improvement on sensing performance is very sensitive to lambda(2)/lambda(1).