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DWT Based Energy Detection Spectrum Sensing Method for Cognitive Radio System

AbstractIn this paper a new blind energy detection spectrumsensing method based on Discreet Wavelet Transform (DWT) is proposed. The method utilizes the DWT sub-band to collect the received energy. The proposed method recognizes the Primary User (PU) signal from noise only signal by using the differences in the collected energy in first and last sub-bands of one DWT level. The simulation results show that in the AWGN channel, the proposed method improves detection probability by a factor of 40% at Signal to Noise Ratio (SNR) equals -13 dB compared to Conventional Energy Detector (CED). Furthermore, the proposed method reduces the number of sensed samples to 50% on what in the traditional method. Thus, the proposed method achieves shorter sensing time and consumes lower Energy which makes it suitable for Cognitive Radio ( CR) applications where only limited energy like device battery is available.