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arXiv · 2502.09835

Determining angle of arrival of radio frequency fields using subwavelength, amplitude-only measurements of standing waves in a Rydberg atom sensor

Rajavardhan Talashila·William J. Watterson·Benjamin L. Moser·Joshua A. Gordon·Alexandra B. Artusio-Glimpse·Nikunjkumar Prajapati·Noah Schlossberger·Matthew T. Simons·Christopher L. Holloway
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Abstract

Deep subwavelength RF imaging with atomic Rydberg sensors has overcome fundamental limitations of traditional antennas and enabled ultra-wideband detection of omni-directional time varying fields all in a compact form factor. However, in most applications, Rydberg sensors require the use of a secondary strong RF reference field to serve as a phase reference. Here, we demonstrate a new type of Rydberg sensor for angle-of-arrival (AoA) sensing which utilizes subwavelength imaging of standing wave fields. By placing a metallic plate within the Rydberg cell, we can determine the AoA independent of the strength of incoming RF field and without requiring a secondary strong RF phase reference field. We perform precision AoA measurements with a robotic antenna positioning system for 4.2, 5.0, and 5.7 GHz signals and demonstrate a 1.7 deg polar angular resolution from 0 deg to 60 deg AoA and 4.1 deg over all possible angles.

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Rajavardhan Talashila, William J. Watterson, Benjamin L. Moser, Joshua A. Gordon, Alexandra B. Artusio-Glimpse, Nikunjkumar Prajapati, Noah Schlossberger, Matthew T. Simons, Christopher L. Holloway. 2025-02-14. Determining angle of arrival of radio frequency fields using subwavelength, amplitude-only measurements of standing waves in a Rydberg atom sensor. https://doi.org/10.1063/5.0285778

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