Double Stage Energy Detectors for Sensing Spectrum in Cognitive Radio Networks

This paper presents double stage energy detectors for spectrum sensing (SS). The first stage carries fixed threshold (FT) based energy detector (ED), and the second stage carries adaptive double threshold (ADT) based ED. Numerical analysis has been carried out on the basis of results obtained and shows that proposed scheme outperforms the cyclostationary based sensing method and adaptive SS by 12.9% and 15% at -- 8 dB signal-to-noise ratio (SNR), respectively. It also shows that the proposed scheme takes shorter detection time period than cyclostationary detection and adaptive SS scheme in the order of 5 ms and 0.8 ms at - 20 dB SNR , respectively.