Cooperative spectrum sensing has been widely used to detect the primary user with a high agility and accuracy. However, the limitation of control channel bandwidth is a challenge of cooperative spectrum sensing when the number of cognitive users becomes very large. In this paper, weighted-clustering algorithm is proposed to avoid the congestion on the control channel and lessen the sensing delay. Multi-threshold mechanism is used to reduce transmission overhead and improve the sensing performance. Furthermore, algorithm flow and algorithm exception processing are both studied and the analytical performance results are given. Numerical results show that the sensing performance is improved significantly as opposed to conventional sensing algorithm.