SNR Wall Effect Alleviation by Generalized Detector Employed in Cognitive Radio Networks

Sensors (Basel). 2015 Jul 3;15(7):16105-35. doi: 10.3390/s150716105.

Abstract

The most commonly used spectrum sensing techniques in cognitive radio (CR) networks, such as the energy detector (ED), matched filter (MF), and others, suffer from the noise uncertainty and signal-to-noise ratio (SNR) wall phenomenon. These detectors cannot achieve the required signal detection performance regardless of the sensing time. In this paper, we explore a signal processing scheme, namely, the generalized detector (GD) constructed based on the generalized approach to signal processing (GASP) in noise, in spectrum sensing of CR network based on antenna array with the purpose to alleviate the SNR wall problem and improve the signal detection robustness under the low SNR. The simulation results confirm our theoretical issues and effectiveness of GD implementation in CR networks based on antenna array.

Keywords: SNR wall; antenna array; cognitive radio (CR); energy detector (ED); generalized detector (GD); noise uncertainty; sample complexity; spectrum sensing.