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arXiv · 1910.13040

Dispersion independent long-haul photon counting OTDR

Bin Li·Ruiming Zhang·Yong Wang·Hao Li·Lixing You·Zhonghua Ou·Heng Zhou·Yun Ling·Yunxiang Wang·Guangwei Deng·You Wang·Haizhi Song·Kun Qiu·Qiang Zhou
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Abstract

Photon counting optical time-domain reflectometry (PC-OTDR) based on the single photon detection is an effective scheme to attain the high spatial resolution for optical fiber fault monitoring. Currently, due to the spatial resolution of PC-OTDR is proportional to the pulse width of a laser beam, short laser pulses are essential for the high spatial resolution. However, short laser pulses have a large bandwidth, which would be widened by the dispersion of fiber, thereby causing inevitable deterioration in spatial resolution, especially for long-haul fiber links. In this letter, we propose a scheme of dispersion independent PC-OTDR based on an infinite backscatter technique. Our experimental results -with more than 50 km long fiber - show that the spatial resolution of the PC-OTDR system is independent with the total dispersion of the fiber under test. Our method provides an avenue for developing the long-haul PC-OTDR with high performance.

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Bin Li, Ruiming Zhang, Yong Wang, Hao Li, Lixing You, Zhonghua Ou, Heng Zhou, Yun Ling, Yunxiang Wang, Guangwei Deng, You Wang, Haizhi Song, Kun Qiu, Qiang Zhou. 2019-10-29. Dispersion independent long-haul photon counting OTDR. https://arxiv.org/abs/1910.13040

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