Optimal Non-Identical Sensing Setting for Multi-Channel Cooperative Sensing

In this paper, optimal multiple channels cooperative spectrum sensing setting in non-identical environment is investigated. In previous work on cooperative sensing, all the secondary users have the same detection threshold and the noise received is independent identically distributed random variable. Thus researchers often assume that identical sensing time is assigned to the channels for spectrum sensing. In our paper, secondary users cooperatively sense the channel and send the binary results to the common receiver where energy detection with hard decision rule is employed. We assume that secondary users can assign individual sensing time to the channel with possibly different noise powers and detection thresholds. An iterative algorithm with polynomial complexity is established to determine the optimal sensing sequence for the secondary users to assign the mini-slots to the channels, such that the throughput increase can be maximized in each iteration. Furthermore, a new performance metric delay sensitivity is introduced to evaluate how long the authorized transmitting users need to wait for data transmission. Simulation results show that this iterative algorithm can yield better performance in cooperative spectrum sensing than other schemes with identical sensing setting in terms of both achievable throughput and delay sensitivity.