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arXiv · 2005.02571

Identifying Unused RF Channels Using Least Matching Pursuit

Emre Gönültaş·Milad Taghavi·Sweta Soni·Alyssa B. Apsel·Christoph Studer
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Abstract

Cognitive radio aims at identifying unused radio-frequency (RF) bands with the goal of re-using them opportunistically for other services. While compressive sensing (CS) has been used to identify strong signals (or interferers) in the RF spectrum from sub-Nyquist measurements, identifying unused frequencies from CS measurements appears to be uncharted territory. In this paper, we propose a novel method for identifying unused RF bands using an algorithm we call least matching pursuit (LMP). We present a sufficient condition for which LMP is guaranteed to identify unused frequency bands and develop an improved algorithm that is inspired by our theoretical result. We perform simulations for a CS-based RF whitespace detection task in order to demonstrate that LMP is able to outperform black-box approaches that build on deep neural networks.

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Emre Gönültaş, Milad Taghavi, Sweta Soni, Alyssa B. Apsel, Christoph Studer. 2020-05-06. Identifying Unused RF Channels Using Least Matching Pursuit. https://arxiv.org/abs/2005.02571

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