Dispersed chirp-z transform-based spectrum sensing and utilisation in cognitive radio networks

• Published in: IET signal processing Vol. 8; no. 4; pp. 320 - 329
• Main Authors: Namdar, Mustafa, Ilhan, Haci, Durak-Ata, Lutfiye
• Format: Journal Article
• Language: English
• Published: Stevenage The Institution of Engineering and Technology 01.06.2014; Institution of Engineering and Technology; The Institution of Engineering & Technology
• Subjects: additive white Gaussian noise; Applied sciences; AWGN; AWGN channels; Channels; closed‐form expressions; cognitive radio; cognitive radio networks; Derivation; Detection; dispersed chirp‐z transform based spectrum sensing; Dispersion; distributed fading channels; energy detection method; Exact sciences and technology; Fading; fading channels; Information, signal and communications theory; Networks; optimal detection; radio spectrum management; Rayleigh channels; receiver operating characteristics; Rician channels; Signal and communications theory; Signal representation. Spectral analysis; Signal, noise; spectral efficiency; Telecommunications and information theory; Thresholds; Transforms; radio spectrum management; optimal detection; AWGN; receiver operating characteristics; Rayleigh channels; transforms; closed-form expressions; energy detection method; cognitive radio networks; AWGN channels; cognitive radio; fading channels; dispersed chirp-z transform based spectrum sensing; Rician channels; spectral efficiency; additive white Gaussian noise; distributed fading channels; Fading channels; Performance evaluation; Chirp; Error rate; Optimal detection; Simulation; Z transformation; Spectrum analysis; Frequency spectrum; Signal analysis; Radio communication; Software radio
• ISSN: 1751-9675; 1751-9683; 1751-9683
• DOI: 10.1049/iet-spr.2013.0127

The authors propose novel spectrum sensing and utilisation schemes for cognitive radio networks using the chirp-z transform. To improve the spectral efficiency, a dispersed chirp-z transform is introduced with the energy detection method. The dispersed chirp-z transform enables one to analyse the dispersed frequency spectrum of any frequency range of interest. The analysis is first focused on the sensing part, including the derivations of closed-form expressions for the optimal detection thresholds minimising the total error rate over additive white Gaussian noise (AWGN), Rayleigh, Rician and log-normally distributed fading channels. Then, the performance analysis of the proposed system is investigated for efficient spectrum utilisation over AWGN and fading channels by presenting the receiver operating characteristics. Conventional and segmented chirp-z transform-based spectrum utilisation techniques are also introduced for performance comparison purposes. Finally, the theoretical framework and the optimal threshold derivations through simulations are verified. The analyses reveal that the proposed schemes have a considerable potential to improve the non-cooperative spectrum sensing and utilisation performance.