174 / 2015-11-26 14:08:21

Hilbert Transform based edge detection approach for Wideband Spectrum Sensing in Cognitive Radios

Cognitive radios,Edge detection,soft de-noising,Hilbert transform

Cognitive radio is now come into attention for researchers as a new source of mitigating the fast growing bandwidth demand. Spectrum sensing is a major problem for dynamic spectrum management in cognitive radio networks. This paper introduces a simple Hilbert transform based approach for efficient spectrum sensing of wideband channel in which soft de-noising is used to suppress the noise level. In this approach the effect of noise is suppressed first by averaging PSD of the received signal then de-noised by soft thresholding. Frequency boundaries of bands are found by Hilbert transform and characterized by vacant or occupied by determining the average PSD of the consecutive bands which is shown in simulation result. Our proposed method has also improved performance in low SNR region than the conventional methods which is also portrayed by simulation result.