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arXiv · 2511.18400

High-Spatial-Resolution Optical Correlation-Domain Reflectometry with 100-km Measurement Range

Takaki Kiyozumi·Soshi Yoshida·Yuta Higa·Keisuke Motoda·Sze Yun Set·Shinji Yamashita·Yosuke Mizuno
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Abstract

In the maintenance of optical fiber networks, there is a growing demand for high-precision measurement of optical loss distribution and fault locations over long distances. In this study, we propose an OCDR method incorporating periodic pseudo-random modulation (PPRM), and demonstrate that it enables the acquisition of loss distribution based on Rayleigh scattering and the positions of reflection points in an approximately 100-km optical fiber, with a spatial resolution of about 19 cm and a measurement time of about 20 seconds.

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Takaki Kiyozumi, Soshi Yoshida, Yuta Higa, Keisuke Motoda, Sze Yun Set, Shinji Yamashita, Yosuke Mizuno. 2025-11-23. High-Spatial-Resolution Optical Correlation-Domain Reflectometry with 100-km Measurement Range. https://arxiv.org/abs/2511.18400

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