Publications de Sheng Wang | EPFL Graph Search

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

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang, Jian Wu, 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

Genetic-optimised aperiodic code for distributed optical fibre sensors

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Simon Adrien Zaslawski, Zhisheng Yang, Jian Wu, Sheng Wang

Distributed optical fibre sensors deliver a map of a physical quantity along an optical fibre, providing a unique solution for health monitoring of targeted structures. Considerable developments over recent years have pushed conventional distributed sensor ...

Nature Research2020

Optical fibre sensing for fast hotspot detection in SFCLs

Bertrand Dutoit, Luc Thévenaz, Bertrand Dutoit, Arooj Akbar, Zhisheng Yang, Sheng Wang

The health monitoring of superconducting fault current limiters (SFCL) is important for their large-scale exploitation in HVDC grids protection. The intrinsic non-homogeneity of critical current along the superconductor length can cause localized points of ...

2020

Study on the signal-to-noise ratio of Brillouin optical-time domain analyzers

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

The signal-to-noise ratio (SNR) of Brillouin optical time-domain analyzers (BOTDA) is modelled and experimentally validated, using direct detection with and without the use of optical pre-amplification. The behavior of SNR as a function of the Brillouin ga ...

2020

Short spatial resolutions retrieval from a long pulse BOTDA trace

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

A novel, to the best of our knowledge, postprocessing technique is proposed to extract with a flexible and variable spatial resolution the information from Brillouin optical time-domain analyzers, obtained using a pulse longer than the acoustic settling ti ...

2020

Short spatial resolutions retrieval from a long pulse BOTDA trace

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

A novel technique is proposed to obtain a flexible and variable spatial resolution from a conventional Brillouin optical time-domain analyzers using a fast post-processing algorithm. The approach is very attractive since a fine spatial resolution can be ob ...

SPIE2019

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

Distributed forward stimulated Brillouin scattering measurement using broadband BOTDR

Luc Thévenaz, Simon Adrien Zaslawski, Zhisheng Yang, 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

Boosting the performance of distributed optical fiber sensors based on adaptive decoder

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

An adaptive decoder is proposed to derive the fiber single-pulse response. This experimentally simple technique simultaneously improves the measurement time and the noise level, boosting to an uncommon degree the overall performance of distributed fiber se ...

Optical Society of America2018