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Updated: Oct 20, 2025

Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping

Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping

Published on: March 20, 2017

Frequency multiplexed coherent φ-OTDR.

Hannah M Ogden¹, Matthew J Murray², Joseph B Murray²

¹U.S. Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC, 20375, USA. hannah.ogden.ctr@nrl.navy.mil.

Scientific Reports

|September 10, 2021

Summary

This study introduces a novel frequency multiplexed phase-measuring distributed fiber optic sensor. The advanced system significantly reduces noise and improves linearity for enhanced strain detection over long distances.

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Area of Science:

Optoelectronics
Fiber Optic Sensing
Photonics

Background:

Distributed fiber optic sensing is crucial for structural health monitoring.
Traditional phase-measuring reflectometry (φ-OTDR) faces challenges with noise and fading.

Purpose of the Study:

To analyze a frequency multiplexed phase-measuring φ-OTDR sensor platform.
To enhance sensor performance through increased power and diverse measurements.

Main Methods:

Utilized a train of frequency-shifted pulses for increased injected power.
Combined simulations, numerical analysis, and experimental measurements.
Investigated sensor dependence on pulse train length and characterized performance versus range.

Main Results:

Demonstrated lower noise and mitigated interference fading.
Achieved improved sensor linearity.
Showcased operation from 1 to 50 km with a minimum detectable strain of 0.6 pε.

Conclusions:

The frequency multiplexed φ-OTDR platform offers state-of-the-art performance.
The system exhibits low crosstalk, high linearity, and excellent sensitivity.
This approach provides a robust solution for long-range, high-resolution strain sensing.