An Image Processing Approach to Wideband Spectrum Sensing of Heterogeneous Signals

• Published in: Cognitive Radio Oriented Wireless Networks Vol. 261; pp. 211 - 221
• Main Authors: Nguyen, Ha Q., Nguyen, Ha P. K., Nguyen, Binh T.
• Format: Book Chapter
• Language: English
• Published: Switzerland Springer International Publishing AG 2019; Springer International Publishing
• Series: Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering
• Subjects: Blob extraction; Frequency hopping; Image morphology; Spectrogram; Time-frequency analysis; Waterfall image; Wideband spectrum sensing; Wireless signal detection
• ISBN: 9783030054892; 3030054896
• ISSN: 1867-8211; 1867-822X
• DOI: 10.1007/978-3-030-05490-8_20

We introduce a simple yet efficient framework for the localization and tracking of fixed-frequency and frequency-hopping (FH) wireless signals that coexist in a wide radio-frequency band. In this spectrum sensing scheme, an energy detector is applied to each Short-time Fourier Transform of the wideband signal to produce a binary spectrogram. Bounding boxes for narrowband signals are then identified by using image processing techniques on a block of the spectrogram at a time. These boxes are also tracked along the time axis and fused with the newly detected boxes to provide an on-line system for spectrum sensing. Fast and highly accurate detection is achieved in simulations for various FF signals and FH signals with different hopping patterns and speeds. In particular, for the SNR of 4 dB over a bandwidth of 50 MHz, 97.98% of narrowband signals were detected with average deviations of about \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$0.02\,\mathrm{ms}$$\end{document} in time and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$2.15\,\mathrm{KHz}$$\end{document} in frequency.