Throughput maximization for cognitive radio networks with time-domain combining cooperative spectrum sensing

To improve the sensing performance, cooperation among cognitive users can be utilized to collect space diversity. In this paper, we propose a novel time-domain cooperative spectrum sensing framework, in which the time consumed by reporting for one cognitive user is also utilized for other cognitive users' sensing. For time varying channels, the novel time-domain combining cooperative spectrum sensing is derived. We focus on the optimal sensing settings to maximize the throughput of the secondary network under the constraint that the primary users are sufficiently protected. Some simple algorithms are also derived to calculate the optimal solutions. Simulation results show that fundamental improvement of the achievable throughput can be obtained by optimal sensing settings. In addition, the novel time-domain cooperative spectrum sensing scheme shows a much larger throughput than cooperative sensing based on general frame structure.