Improved energy detector with weights for primary user status changes in cognitive radios networks

The spectrum sensing performance is significantly degraded by the primary user´s status changes as arriving or leaving randomly in cognitive radio networks. This paper presents an improved energy detector (ED) with weights to improve detection performance in this situation. The idea is derived from the concept of unequal scale sampling such that the sampling points in the sensing period are endowed with monotonic weights. Numerical simulation results show that the proposed ED offers better detection performances with a reduced probability of false alarm compared to conventional ED.