Title :
Wideband Spectrum Sensing for Cognitive Radios With Correlated Subband Occupancy
Author :
Hossain, Khalid ; Champagne, Benoît
Author_Institution :
Dept. of Electr. & Comput. Eng., McGill Univ., Montreal, QC, Canada
Abstract :
In this letter, we consider wideband spectrum sensing in the presence of correlation between the occupancies of frequency subbands. We begin by formulating the maximum a posteriori (MAP) estimator of channel occupancy based on measurements from multiple frequency subbands. Since the MAP estimator´s complexity grows exponentially with the number of subbands, we propose an alternative structure, in which the subband energy measurements are linearly combined according to a minimum mean-square error (MMSE) criterion to form a sufficient statistic for binary detection in each subband. Through analysis and numerical simulations, we show that the proposed frequency-coupled detector can significantly outperform the traditional decoupled one.
Keywords :
cognitive radio; correlation methods; energy measurement; least mean squares methods; maximum likelihood estimation; radio spectrum management; spectral analysis; wireless channels; MAP estimator; MMSE criterion; binary detection; channel occupancy; cognitive radio; correlated subband occupancy; frequency-coupled detector; maximum a posteriori estimator; minimum mean-square error criterion; multiple frequency subband; numerical simulation; subband energy measurement; wideband spectrum sensing; Channel estimation; Cognitive radio; Correlation; Detectors; Probability; Wideband; Channel occupancy estimation; cognitive radio; hypothesis-testing; spectrum sensing;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2010.2091405