Statistical Model of Time-varying Backscatter Power of Monostatic RF Sensing Channels in Urban Canyons

Dmitry Chizhik; Jakub Sapis; John Drogo; Abhishek Adhikari; Manuel Almendra; Jinfeng Du; Reinaldo A. Valenzuela; Gil Zussman; Mauricio Rodriguez; Rodolfo Feick

arXiv · 2605.04292

Statistical Model of Time-varying Backscatter Power of Monostatic RF Sensing Channels in Urban Canyons

Dmitry Chizhik·Jakub Sapis·John Drogo·Abhishek Adhikari·Manuel Almendra·Jinfeng Du·Reinaldo A. Valenzuela·Gil Zussman·Mauricio Rodriguez·Rodolfo Feick

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Abstract

We present a measurement-based statistical model for the backscatter power ratio of monostatic RF sensing in urban canyons with moving clutter, suitable for large-scale system level performance evaluation of RF sensing in 6G networks. A narrowband (CW) 140 GHz sounder used a monostatic radar arrangement with an omnidirectional transmit antenna illuminating streets and a spinning horn 2o receive antenna offset vertically (less than 1 m away) collecting backscattered power as a function of azimuth and time below building height in Manhattan and Valparaiso, Chile. A concise outdoor deterministic model of average backscattered power dependent on distance to nearest building-wall reproduces observations with 3.3 dB RMS error or better. Distribution of power variation in azimuth around this average is reproduced within 0.5 dB by a random azimuth spectrum with a lognormal distribution. Temporal fluctuations for various antenna aims and locations were found to be well modeled by a Rician distribution, with lognormally distributed K-factor, with 0.47-0.73 correlation coefficient to backscatter power deviation from mean. The statistical model does not require a detailed environmental description, aiming to reproduce backscatter clutter statistics (as opposed to a deterministic response) faithfully and efficiently, essential for large-scale system-level performance evaluation.

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Dmitry Chizhik, Jakub Sapis, John Drogo, Abhishek Adhikari, Manuel Almendra, Jinfeng Du, Reinaldo A. Valenzuela, Gil Zussman, Mauricio Rodriguez, Rodolfo Feick. 2026-05-05. Statistical Model of Time-varying Backscatter Power of Monostatic RF Sensing Channels in Urban Canyons. https://arxiv.org/abs/2605.04292

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