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arXiv · 2510.22499

Rapidly Tunable Synthetic Wavelength Ranging with an RFSoC

Shawn M. P. McSorley·Benjamin P. Dix-Matthews·Andrew M. Lance·David R. Gozzard·Sascha W. Schediwy
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Abstract

Measurements of optical range and time-of-flight are crucial for a variety of high-precision technologies. Competitive optical measurement techniques have been developed that balance precision with accuracy and system complexity. Here, we present a continuous-wave synthetic wavelength interferometry technique that employs digitally tunable electro-optic frequency combs. With a software-defined radio, our approach can dynamically sweep the synthetic wavelength and measure absolute optical range. We demonstrate this digital approach over a free-space optical delay line of 1 m and over an 40 km fiber link. The best obtained precision over the delay line is better than 60 nm (0.2 fs). Through a 40 km fiber spool, this precision degrades to 15 um (50 fs), which is a fractional error on the order of 2e-10 m/m. Our design is simple to implement, and only relies on continuous-wave interference, decreasing system complexity.

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Shawn M. P. McSorley, Benjamin P. Dix-Matthews, Andrew M. Lance, David R. Gozzard, Sascha W. Schediwy. 2025-10-26. Rapidly Tunable Synthetic Wavelength Ranging with an RFSoC. https://arxiv.org/abs/2510.22499

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