Optimization of multi-cluster multi-group based cooperative sensing in cognitive radio networks

In cognitive radio (CR) networks, there are two parameters associated with spectrum sensing: probability of detection (PoD) and probability of false alarm (PoF). The higher the PoD, the better the primary users (PUs) are protected. On the other hand, the lower the PoF, the more the throughput of secondary users (SUs) can be achieved. When the cooperative spectrum sensing is used, the performance of these two parameters depends heavily on the fusion scheme. In this paper, the multi-cluster multi-group based cooperative spectrum sensing scheme is proposed. By using k-out-of-N fusion rule, we obtain the optimal number of groups which minimizes the error rate of a cluster. Computer simulations show that the significant improvement of the total error rate in CR networks can be achieved when optimized parameters from the k-out-of-N fusion rule are used.