Conference Paper

Spectrum Sensing via Energy Detector in Low SNR

Dept. of Electr. & Comput. Eng., Univ. of Alberta, Edmonton, AB, Canada
DOI: 10.1109/icc.2011.5963316 Conference: Communications (ICC), 2011 IEEE International Conference on
Source: IEEE Xplore

ABSTRACT As required in the IEEE 802.22 proposal, spectrum sensing techniques should be capable enough to sense the primary signal with very low receiver sensitivity such as at -116 dBm. In this paper, the detection performance of an energy detector used for spectrum sensing in cognitive radio networks is investigated under such very low signal-to-noise ratio (SNR) levels. The analysis focuses on the derivation of a closed-form expression for the average missed-detection probability over Rayleigh fading and Nakagami-m fading channels. Subsequently, the detection threshold is optimized for minimizing the total error rate. The analysis is validated by numerical and simulation results. The sensing requirements defined in IEEE 802.22 are also discussed with numerical examples.

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