Abstract-In cognitive radio networks, the first cognitive a filterbank for wid.eband, sensing [4] , but this architecture task preceding any form of dynamic spectrum management requires an increased, number of components and the filter is the sensing and identification of spectrum holes in wireless range of each BPF is preset. In future networks where specenvironments. This paper develops a wavelet approach to efficient spectrum sensing of wideband channels. The signal spectrum trum utilization is high (above 20%), the significant spectrum over a wide frequency band is decomposed into elementary scarcity would call for different spectrum sharing mechanisms building blocks of subbands that are well characterized by local such as ultra-wideband cognitive radios [7] , which in turn irregularities in frequency. As a powerful mathematical tool entail different sensing tasks for spectrum overlay. for analyzing singularities and edges, the wavelet transform is In this paper, we focus on the wideband spectrum sensing employed to detect and estimate the local spectral irregular task without resoring to multiple narrowband BPFs. Our structure, which carries important information on the frequency tas toidentify to fe ultionsofbndoBPping locations and power spectral densities of the subbands. Along goal is to identify the frequency locations of non-overlapping this line, a couple of wideband spectrum sensing techniques are spectrum bands and categorize these bands into black, gray developed based on the local maxima of the wavelet transform or white spaces, corresponding to the power spectral density modulus and the multi-scale wavelet products. The proposed (PSD) levels being high, medium or low [3] . In a peer-tosensing techniques provide an effective radio sensing architecture to identify and locate spectrum holes in the signal spectrum. peer network adoptig the equal-sharing spectrum allLocation paradigm, white spaces are treated as spectrum holes that can
Wavelet detection uses the wavelet transform to detect discontinuities in the power spectrum density (PSD) of the signal received by a CR, thus defining the frequency boundaries in the primary signal REF .
A Wavelet Approach to Wideband Spectrum Sensing for Cognitive Radios
2006 1st International Conference on Cognitive Radio Oriented Wireless Networks and Communications
2006 1st International Conference on Cognitive Radio Oriented Wireless Networks and Communications
Mathematics Computer Science