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Zhisheng Yang

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Publications associées (49)

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Frequency scanned phase sensitive optical time-domain reflectometry interrogation in multimode optical fibers

Luc Thévenaz, Zhisheng Yang, Alejandro Dominguez Lopez

Standard multimode optical fibers normally support transmission over some 100 modes. Large differences in the propagation constant and the spatial distribution of distinct modes degrade the performance of phase-sensitive optical time-domain reflectometry m ...

AIP2020

On the 2D Post-Processing of Brillouin Optical Time-Domain Analysis

Luc Thévenaz, Zhisheng Yang, Simon Adrien Zaslawski

The benefits and limitations inherent to the 2D post-processing of measurements from Brillouin optical time-domain analyzers are investigated from a fundamental point of view. In a preliminary step, the impact of curve fitting on the precision of the estim ...

IEEE Institute of Electrical and Electronics Engineers2020

Impact of optical noises on unipolar-coded Brillouin optical time-domain analyzers

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Sheng Wang

Noise models for both single-pulse and coded Brillouin optical time-domain analyzers (BOTDA) are established to quantify the actual signal-to-noise ratio (SNR) enhancement provided by pulse coding at any fiber position and in any operating condition. Simul ...

2021

Reaching the ultimate performance limit given by non-local effects in BOTDA sensors

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Alejandro Dominguez Lopez

Non-local effects have been traditionally identified as one of the most limiting factors of the performance of Brillouin optical time-domain analyzers. These phenomena, directly linked with the energy gained/lost by the pump pulse, limit the probe power an ...

SPIE2015

Distributed optomechanical fiber sensing based on serrodyne analysis

Luc Thévenaz, Zhisheng Yang, Simon Adrien Zaslawski

Distributed measurement of forward stimulated Brillouin scattering (FSBS) attracted substantial attention for its ability to probe media surrounding optical fibers. Currently, all techniques extract the information from the FSBS-induced local energy transf ...

2021

High Signal-to-Noise Ratio Stimulated Brillouin Scattering Gain Spectrum Measurement

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Kenny Hey Tow, Flavien Gyger

A technique to measure nonlinear processes, such as stimulated Brillouin scattering, with a very-high signal-to-noise ratio (SNR) is presented. Brillouin gain measurement with 77dB SNR is demonstrated over a 2m-long section of single-mode fiber. ...

Optical Society of America2018

Distributed Acoustic Impedance Measurement Based On Forward Stimulated Brillouin Scattering

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Desmond Chow Ming Chia

A technique to measure the local spectrum of forward stimulated Brillouin scattering (FSBS) along a standard optical fiber is proposed. The local acoustic impedance of surrounding material is retrieved from the measured FSBS resonance linewidth. ...

Optical Society of America2018

Rayleigh-Based Distributed Optical Fiber Sensing Using Least Mean Square Similarity

Luc Thévenaz, Zhisheng Yang, Li Zhang, Flavien Gyger

Large frequency shift errors induced by cross-correlation are investigated in Rayleigh-based distributed sensing. A least mean square method is proposed to reduce those errors, thus increasing the reliability and extending the measurand range. ...

Optical Society of America2018

Hybrid Coding Scheme for Brillouin Optical Time-domain Analysis Based on Golay and Differential Pulses

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang

A hybrid Golay coding method based on differential pulse-pair sequences is proposed for distributed Brillouin sensing. The method provides 1.5 dB signal-to-noise ratio improvement over unipolar Golay with halved measurement time, securing high spatial reso ...

Optical Society of America2018

Optimizing the signal-to-noise ratio for direct-detection BOTDA

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Sheng Wang

The signal-to-noise ratio (SNR) of the measurement for direct-detection Brillouin optical time-domain analyzers is modelled and experimentally validated, with and without the use of optical pre-amplification. Results indicate that preamplification associat ...

SPIE2019

Phase Sensitive OTDR Strain Measurement Using Single Mode Operation in Multimode OM4 Fiber

Luc Thévenaz, Zhisheng Yang, Alejandro Dominguez Lopez

We present the first realization of strain sensing in a multimode OM4 optical fiber using phase-sensitive optical time-domain reflectometry. We demonstrate that single mode operation in an OM4 fiber is achievable and allows the fiber strain to be measured ...

2019

Closed-loop Controlled Brillouin Optical Time-domain Analysis

Luc Thévenaz, Zhisheng Yang

A novel concept to retrieve information in Brillouin distributed fiber sensors is presented, in which the interacting signals are conditioned to track a uniform gain along the fiber, showing 100× faster acquisition at similar accuracy. ...

Optical Society of America2018

Closed-loop technique based on gain balancing for real-time Brillouin optical time-domain analysis

Luc Thévenaz, Zhisheng Yang, Li Zhang, Ana Gabriela Correa Mena

A closed-loop servo control based on balancing the gain of two probing frequencies is proposed for real-time Brillouin optical time-domain analysis (BOTDA) without post-processing. With the most basic BOTDA hardware setup, the system can perform measuremen ...

2022

Distributed forward stimulated Brillouin scattering measurement using broadband BOTDR

Luc Thévenaz, Zhisheng Yang, Simon Adrien Zaslawski, Sheng Wang

Brillouin optical time-domain reflectometry is used to perform distributed forward stimulated Brillouin scattering (FSBS) measurements. This configuration suppresses the need for an additional frequency scanning to evaluate the local Brillouin peak gain wh ...

SPIE2019

Analysis and Reduction of Large Errors in Rayleigh-based Distributed Sensor

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Li Zhang

Commonly, the frequency shift of back-reflection spectra is the key parameter to measure quantitatively local temperature or strain changes in frequency-scanned Rayleigh-based distributed fiber sensors. Cross-correlation is the most common method to estima ...

IEEE Institute of Electrical and Electronics Engineers2019

Distributed measurement of mode group effective refractive index difference in a few mode optical fibers

Luc Thévenaz, Zhisheng Yang, Alejandro Dominguez Lopez

The possibility to perform distributed measurements of the effective refractive index difference between distinct modes in few mode optical fibers is demonstrated using phase sensitive optical time domain reflectometry. Effective refractive index differenc ...

2022

Closed-loop technique using gain balance for fast Brillouin Optical Time-Domain Analysis

Luc Thévenaz, Zhisheng Yang, Li Zhang, Ana Gabriela Correa Mena

A closed-loop servo control based on the gain ratio of two probing frequencies is proposed for fast BOTDA, where the feedback is independent of probe and pump loss, making it robust in harsh environment. ...

Optica Publishing Group2022

High-Resolution Distributed Differential Curvature Measurement Based on Phase-Sensitive Optical Time Domain Reflectometry and Multi-Core Fiber

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Alejandro Dominguez Lopez

A distributed curvature sensor based on multicore fiber and phase-sensitive optical time domain reflectometry is presented, demonstrating a resolution of 10 cm over ~25 m of sensing range. ...

Optical Society of America2018

Closed-loop Controlled Brillouin Optical Time-Domain Analysis

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang

A closed-loop controlled BOTDA distributed optical fibre sensor is proposed for tracking fast temperature-strain evolution. The measurement time is reduced by two orders of magnitude with respect to classical BOTDA sensing, while keeping the same accuracy ...

IEEE2017

High spatial resolution distributed and dynamic strain sensing using direct detection

Luc Thévenaz, Zhisheng Yang, Li Zhang

A distributed dynamic strain sensing system based on frequency-scanned phase-sensitive optical time domain reflectometry is proposed and demonstrated. It demonstrates a record spatial resolution of 20 cm, compared with other direct-detection dynamic strain ...

Optica Publishing Group2021