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arXiv · 2501.15576

First Real-Time Detection of Ambient Backscatters using Uplink Sounding Reference Signals of a Commercial 4G Smartphone

Ahmed ElSanhoury·Islam Galal·Khaled AlKady·Aml ElKhodary·Dinh-Thuy Phan-Huy·Ayman M. Hassan
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Abstract

Recently, cellular Ambient Backscattering has been proposed for cellular networks. Up to now an Ambient backscatter device, called zero-energy device or tag, broadcasted its message by backscattering ambient downlink waves from the closest Base Station (BS) according to a predefined pattern. A tag was detected by smartphones nearby. This paper presents, for the first time, a novel ambient backscatter communication system exploiting uplink ambient waves from smartphones instead of downlink waves. In this novel system, a BS connected to a smartphone monitors the uplink pilot signals and detects TAGs in proximity. The proposed system is implemented and tested with one prototype of TAG, a commercial off-the shelf 4G smartphone and a 4G Software Defined Radio (SDR) BS. Indoor and outdoor experiments were conducted to assess the proposed technique. These very preliminary experiments exhibit a promising potential. In indoor, a detection probability of more than 90% has been achieved without false alarm when the TAG was 3 meters from the UE, and the BS 20 meters away of them, behind walls and obstacles.

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Ahmed ElSanhoury, Islam Galal, Khaled AlKady, Aml ElKhodary, Dinh-Thuy Phan-Huy, Ayman M. Hassan. 2025-01-26. First Real-Time Detection of Ambient Backscatters using Uplink Sounding Reference Signals of a Commercial 4G Smartphone. https://arxiv.org/abs/2501.15576

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