A directly seeking spectrum holes algorithm by compressive sampling

Abstract

Summary The method of cognitive radio (CR) is a promising solution to the problem of spectrum scarcity. One of the crucial tasks in the CR is the spectrum hole (SH) detection. The energy detection (ED) method is the most dominant spectrum sensing approach owing to its low computational complexity and the ability to identify SHs without requiring a priori knowledge of primary transmission characteristics. But it will be accompanied by some problems such as the high sampling rates, the difficult setting for detection threshold, and the complexity. An improved algorithm with directly seeking SHs from compressive sampling via compressive sensing algorithm is proposed in this paper. The sampling rate is decreased by the process of the compressive sampling, and the computation complexity is reduced for the elimination of the construction stage in the proposed algorithm. Besides, the detection threshold is not needed to be set for the method of relative comparison. The simulation results show that the proposed algorithm has a similar probability of detection (POD) of SHs to the traditional ED algorithm and the compressive spectrum sensing algorithm with minimum sampling numbers and lower computation complexity on the condition that the signal noise ratio is beyond 0 dB. It means the proposed algorithm obtains the balance between computing complexity and the sampling rate, and the performance of SH detection is maintained at the same time.