Rapid and precise distance measurement using balanced cross-correlation of a single frequency-modulated electro-optic comb

Zijian Wang; Zhuoren Wan; Jingwei Luo; Yuan Chen; Mei Yang; Qi Wen; Xiuxiu Zhang; Zhaoyang Wen; Shimei Chen; Ming Yan; Heping Zeng

arXiv · 2507.13206

Rapid and precise distance measurement using balanced cross-correlation of a single frequency-modulated electro-optic comb

Zijian Wang·Zhuoren Wan·Jingwei Luo·Yuan Chen·Mei Yang·Qi Wen·Xiuxiu Zhang·Zhaoyang Wen·Shimei Chen·Ming Yan·Heping Zeng

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Abstract

Ultra-rapid, high-precision distance metrology is critical for both advanced scientific research and practical applications. However, current light detection and ranging technologies struggle to simultaneously achieve high measurement speed, accuracy, and a large non-ambiguity range. Here, we present a time-of-flight optical ranging technique based on a repetition-frequency-modulated femtosecond electro-optic comb and balanced nonlinear cross-correlation detection. In this approach, a target distance is determined as an integer multiple of the comb repetition period. By rapidly sweeping the comb repetition frequency, we achieve absolute distance measurements within 500 ns and real-time displacement tracking at single-pulse resolution (corresponding to a refresh rate of 172 MHz). Furthermore, our system attains an ultimate ranging precision of 5 nm (with 0.3 s integration time). Our method uniquely integrates nanometer-scale precision, megahertz-level refresh rates, and a theoretically unlimited ambiguity range within a single platform, while also supporting multi-target detection. These advances pave the way for high-speed, high-precision ranging systems in emerging applications such as structural health monitoring, industrial manufacturing, and satellite formation flying.

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Zijian Wang, Zhuoren Wan, Jingwei Luo, Yuan Chen, Mei Yang, Qi Wen, Xiuxiu Zhang, Zhaoyang Wen, Shimei Chen, Ming Yan, Heping Zeng. 2025-07-17. Rapid and precise distance measurement using balanced cross-correlation of a single frequency-modulated electro-optic comb. https://arxiv.org/abs/2507.13206

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