Throughput optimization of a cognitive radio system based on cooperative sensing with soft combination

In order to maximize the throughput for a cognitive radio network,the cognitive radio network based on cooperative sensing with equal gain combination are taken as an example to establish a throughput optimization model,with the constraint that the primary users are sufficiently protected.The optimization parameters are local sensing time and the number of cooperative users.We have proved that the throughput is a concave function of the local sensing time by the optimization theory.Based on the conclusion,a searching method is proposed to obtain the maximal throughput.Simulation results have validated the theoretical results,and the maximal throughput and the corresponding parameters are given under different sensing overheads.