Investigation on Spectrum Sensing Techniques in Wireless Communication

摘要

Evolving Wireless systems and applications needs huge bandwidths. Bandwidth needs to be efficiently utilized by proper frequency band usage. Available fixed frequency allocation technique is not effective as there will be spectrum which may not be effectively used by primary users (PU) to whom it is allocated. It is essential to explore the methods to utilize spectrum without compromising on performance of any systems. Cognitive radio (CR) is effective solution to solve this problem which effectively sense part of the spectrum availability and measure the usage pattern licensed users in specified band and let secondary applications to use it when free. It is of interest to study different spectral sensing algorithms that goes into CR and understand their performance. In this paper, simulation of energy detection technique is performed using Fast Fourier Transform (FFT), Discrete Cosine transform (DCT) and Discrete Wavelet transform (DWT). A comparison of performance between FFT, DCT and DWT has been done using MATLAB by computing Detection probability (Pd), Misdetection probability (Pm), False alarm probability (Pfa)). It is observed that DWT method has better performance compared to DCT and FFT methods.