Robust Spectrum Sensing Based on Hyperbolic Tangent in Gaussian and Non-Gaussian Noise Environments

Simple and reliable spectrum sensing schemes are important for cognitive radio (CR) to avoid interference to the primary users (PUs). At present, most of the existing sensing schemes are proposed in Gaussian noise. Nevertheless, in practice, CR suffers from non-Gaussian noise such as man-made impulsive noise, ultra-wideband interference and co-channel interference. In this article, to handle the detection performance degradation in non-Gaussian impulsive noise environments, a robust spectrum sensing scheme namely hyperbolic tangent based energy detector (HT-ED) is proposed. The proposed HT-ED is a semi-blind method which does not require any a priori knowledge about the primary user's signals. Furthermore, the HT-ED can provide a superior detection performance compared with the conventional energy detector (ED) in a wide range of non-Gaussian noises. The simulation results show that the proposed HT-ED is very robust against impulsive noises which are modeled as the Laplace or alpha-stable noises. Moreover the detection performance of HT-ED is much better than those of the traditional ED and FLOM-based methods.