Fiber-Optic Sensing Using Frequency-Shifted Interferometry

Fei Ye

The Edward S. Rogers Sr. Department of Electrical and Computer Engineering (Photonics)

Abstract:

Fiber-optic sensors are playing an increasingly important role in sensing technologies. Made of dielectric materials, fiber-optic sensors are immune to electromagnetic interference. They are spark-free and chemically inert, which enables fiber-optic sensors to withstand hazardous or corrosive environments. With various kinds of components such as couplers, circulators, and amplifiers developed for fiber-optic communications, fiber-optic sensors can be linked together to form sensor networks. The capability of measuring multiple sensing points with one sensing system is a unique feature of fiber-optic sensing. Conventional fiber-optic sensor multiplexing methods such as time-division-multiplexing (TDM) and wavelength-division-multiplexing (WDM) either require a pulsed light source with fast electronics (TDM) or prohibit the use of spectrally-overlapped sensors (WDM). In this talk, a novel fiber-optic sensor multiplexing scheme will be explained. Referred to as frequency-shifted interferometry (FSI), the technique only needs a tunable continuous-wave laser, a slow detector, and an acousto-optic modulator. FSI is able to address the sensors from their locations, and therefore allows spectral overlap. Its applications in strain monitoring and chemical gas sensing will be presented.

 

Biography:

Fei Ye received his B.Sc. degree in applied physics in 2006, and M.A.Sc. degree in electrical engineering in 2008, both from the University of Toronto, where he is currently working toward the Ph.D. degree in photonics at the Department of Electrical and Computer Engineering. His research includes fiber-optic sensors and their multiplexing. Mr. Ye is a student member of the Optical Society of America (OSA) and the president of the OSA Student Chapter at the University of Toronto.