Name of the Speaker: Neethu Sasikumar (EE18D043)
Guide: Dr. Balaji Srinivasan
Venue/Online meeting link: meet.google.com/qwg-vbqo-uio
Date/Time: 29th July, 11:00 am
Rayleigh Scattering based Distributed Acoustic Sensors are capable of both detecting and quantifying dynamic perturbations such as vibrations along the complete length of the sensing fiber. They are widely used in intrusion sensing, pipeline monitoring, structural health monitoring and in seismology fields. The basic working principle of a distributed sensing system is the same as that of Phase OTDR, which extracts the phase of the backscattered signal from an optical fiber. The phase of the signal varies with position of the fiber as well as with time due to refractive index variations induced by dynamic strains. Extracting the phase for consecutively obtained OTDR traces can give the relative phase change at any point along the fiber with time.
In this talk, we discuss the modeling of a DAS based on Rayleigh scattering, analysis of different phase extraction methods through simulation and experimental studies on phase extraction using coherent detection. Challenges and limitations in this field and performance enhancing techniques are also discussed.