Publications by Suneetha Sebastian

Analytical prediction of the final error due to noise in a ϕ-OTDR system

Luc Thévenaz, Malak Mohamed Hossameldeen Omar Mohamed Galal, Yuting Yang, Li Zhang, Suneetha Sebastian

An analytical expression to estimate the uncertainty on the frequency shift in ϕ-OTDR systems is established and confirmed by actual data. ...

Optica Publishing Group2022

Enhanced Signal-Associated Noise in a φ-OTDR System

Luc Thévenaz, Malak Mohamed Hossameldeen Omar Mohamed Galal, Suneetha Sebastian

Owing to their high sensitivity with respect to external measurands, Rayleigh-based distributed optical fiber sensors (DOFS) find their way into applications in many industrial and academic sectors. To further transcend the limit of these sensors in terms ...

2022

On the Measurement Accuracy of Coherent Rayleigh-based Distributed Sensors

Luc Thévenaz, Malak Mohamed Hossameldeen Omar Mohamed Galal, Li Zhang, Simon Adrien Zaslawski, Suneetha Sebastian

The phase change of back-scattered light due to external perturbations is retrieved in coherent Rayleigh-based distributed sensors by estimating the frequency shift (FS) between the traces of different measurements. The uncertainty associated with the esti ...

2021

Determination of the Measurement Accuracy of a Phase-sensitive OTDR

Luc Thévenaz, Malak Mohamed Hossameldeen Omar Mohamed Galal, Zhisheng Yang, Suneetha Sebastian

This paper presents the measurement accuracy of a phase-sensitive optical time-domain reflectometer (ϕ-OTDR) as a function of SNR and pulse width. A method to determine the absolute SNR of a ϕ-OTDR system is also proposed. ...

OSA2021

FBG Tactile Sensor for Surface Thickness and Shape Measurement

Suneetha Sebastian

In recent years, numerous measurement techniques have been employed to characterize surface textures in the micrometer and nanometer range. Although these techniques have enabled significant advances in surface metrology, larger surface details are not eas ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2021

Distributed Temperature Sensing Based on φ-OTDR Using Back-reflection-enhanced Fiber

Luc Thévenaz, Malak Mohamed Hossameldeen Omar Mohamed Galal, Li Zhang, Suneetha Sebastian

Distributed temperature sensing with 10 dB back-reflection-enhanced fiber is performed based on φ-OTDR. While the temperature sensitivity of such fibers is similar to that of standard single-mode fibers, a 3-times higher temperature resolution is observed. ...

Optical Society of America2021

A Study on MoS2 Nanolayer Coated Etched Fiber Bragg Grating Strain Sensor

Suneetha Sebastian

In this paper, we report on the comprehensive study on Molybdenum disulfide (MoS2) nanolayer coated etched Fiber Bragg Grating (eFBG) strain sensor. MoS2 nanolayer is coated using Physical Vapor Deposition (PVD) of Molybdenum (Mo) on eFBGs followed by sulf ...

2021