@article {VazquezValcarceTSP11,
	title = {Spectrum Sensing Exploiting Guard Bands and Weak Channels},
	journal = {IEEE Trans. on Signal Processing},
	volume = {59},
	number = {12},
	year = {2011},
	month = {12/2011},
	pages = {6045-6057},
	abstract = {<div>We address the problem of primary user detection\&nbsp;in Cognitive Radio from a wideband signal comprising multiple\&nbsp;primary channels, exploiting a priori knowledge about the\&nbsp;primary network: channelization and spectral shape of primary\&nbsp;transmissions. Using this second-order statistical information, a\&nbsp;multichannel Gaussian model is formulated. In order to obtain\&nbsp;a Generalized Likelihood Ratio Test, we first address Maximum\&nbsp;Likelihood (ML) estimation of the power levels at the different\&nbsp;channels, as well as of the noise variance. The ML conditions\&nbsp;suggest a suboptimal closed-form estimate, which takes the form\&nbsp;of a constrained Least Squares estimator whose asymptotic\&nbsp;efficiency is shown for flat bandpass spectra in white noise, a\&nbsp;case of practical importance. The resulting detectors exploit those\&nbsp;frequency bins corresponding to guard bands and to primary\&nbsp;channels perceived as weak to improve noise variance estimation.\&nbsp;Analytical expressions for the probabilities of detection and false\&nbsp;alarm are presented. Performance is evaluated via simulations\&nbsp;in the setting of a terrestrial TV primary network with realistic\&nbsp;channelization parameters.</div>},
	keywords = {cognitive radio, dynacs, spectrum sensing},
	doi = {10.1109/TSP.2011.2167615},
	author = {Gonzalo V{\'a}zquez-Vilar and R. L{\'o}pez-Valcarce}
}
