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Related Experiment Video

Updated: Oct 21, 2025

Quasi-light Storage for Optical Data Packets
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Quadratic phase coding for SNR improvement in time-expanded phase-sensitive OTDR.

Miguel Soriano-Amat, Hugo F Martins, Vicente Durán

    Optics Letters
    |September 1, 2021
    PubMed
    Summary
    This summary is machine-generated.

    A new spectral phase coding method enhances time-expanded phase-sensitive optical time-domain reflectometry (TE-ΦOTDR) sensors. This technique improves the signal-to-noise ratio (SNR) by up to 8 dB, offering better performance for fiber optic sensing.

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    Area of Science:

    • Optical sensing
    • Fiber optics
    • Metrology

    Background:

    • Time-expanded phase-sensitive optical time-domain reflectometry (TE-ΦOTDR) is a distributed fiber sensing technique.
    • It offers centimeter-scale resolution and low MHz detection bandwidth.
    • Increasing the signal-to-noise ratio (SNR) is crucial for enhancing sensor performance.

    Purpose of the Study:

    • To present a novel spectral phase coding methodology for TE-ΦOTDR.
    • To improve the SNR of the TE-ΦOTDR sensor beyond existing random phase coding methods.

    Main Methods:

    • Implementation of a specific spectral phase coding methodology using quadratic spectral phase.
    • Precise control of the peak power of dual comb signals in the fiber interrogation process.
    • Experimental validation of the proposed coding technique.

    Main Results:

    • Achieved an SNR improvement of up to 8 dB compared to random phase coding.
    • Demonstrated the effectiveness of quadratic spectral phase coding in enhancing TE-ΦOTDR performance.
    • Successfully controlled peak power of comb signals for improved SNR.

    Conclusions:

    • The proposed quadratic spectral phase coding significantly enhances the SNR of TE-ΦOTDR.
    • This method offers a practical approach to improving distributed optical fiber sensing capabilities.
    • The technique provides a substantial performance gain for fiber optic sensing applications.