An Adaptive Spectrum-Sensing Algorithm for Cognitive Radio Networks based on the Sample Covariance Matrix

Chhagan Charan; Rajoo Pandey

doi:10.14429/dsj.67.10506

Chhagan Charan Department of Electronics and Communication Engineering, National Institute of Technology, Kurukshetra - 136 119
Rajoo Pandey Department of Electronics and Communication Engineering, National Institute of Technology, Kurukshetra - 136 119

DOI: https://doi.org/10.14429/dsj.67.10506

Keywords: Cognitive radio, Spectrum sensing, Covariance matrices, Adaptive threshold, Signal to noise ratio

Abstract

A novel adaptive threshold spectrum sensing technique based on the covariance matrix of received signal samples is proposed. The adaptive threshold in terms of signal to noise ratio (SNR) and spectrum utilisation ratio of primary user is derived. It considers both the probability of detection and the probability false alarm to minimise the overall decision error probability. The energy- based spectrum sensing scheme shows high vulnerability under noise uncertainty and low SNR. The existing covariance-based spectrum sensing technique overcomes the noise uncertainty problem but its performance deteriorates under low SNR. The proposed covariance-based scheme effectively addresses the low SNR problem. The superior performance of this scheme over the existing covariance-based detection method is confirmed by the simulation results in terms of probability of detection, probability of error, and requirement of samples for reliable detection of spectrum.

Author Biographies

Chhagan Charan, Department of Electronics and Communication Engineering, National Institute of Technology, Kurukshetra - 136 119

Mr Chhagan Charan received his BTech (Electr. Comm. Engg.) and MTech (Microwave and Optical Comm. Engg.) from Delhi Technological University (DTU), Delhi. He is working as an Assistant Professor in the Department of Electronics and Communication Engineering, National Institute of Technology Kurukshetra, India. His research interests include: Cognitive radio, digital communication, microwave engineering, wireless sensor networks, and next generation of communication systems.

Rajoo Pandey, Department of Electronics and Communication Engineering, National Institute of Technology, Kurukshetra - 136 119

Dr Rajoo Pandey received his BE from Government Engineering College, Jabalpur, and MTech from NIT-Kurukshetra (formerly REC Kurukshetra). He received his PhD from Indian Institute of Technology, Roorkee, in 2001. He is presently working as a Professor in the Department of Electronics and Communication Engineering, National Institute of Technology Kurukshetra, India. His research interests include: Signal processing, communication systems, digital signal processing, image processing and cognitive radio etc.