title: Frequency-shifted interferometry--a versatile fiber-optic sensing technique.
abstract: Fiber-optic sensing is a field that is developing at a fast pace. Novel fiber-optic sensor designs and sensing principles constantly open doors for new opportunities. In this paper, we review a fiber-optic sensing technique developed in our research group called frequency-shifted interferometry (FSI). This technique uses a continuous-wave light source, an optical frequency shifter, and a slow detector. We discuss the operation principles of several FSI implementations and show their applications in fiber length and dispersion measurement, locating weak reflections along a fiber link, fiber-optic sensor multiplexing, and high-sensitivity cavity ring-down measurement. Detailed analysis of FSI system parameters is also presented.
authors: The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada. fei.ye@mail.utoronto.ca.
authors: Fei
authors: F
authors: Ye
authors: The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada. yiwei.zhang@mail.utoronto.ca.
authors: Yiwei
authors: Y
authors: Zhang
authors: Quantum Information Science Group, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37830, USA. qib1@ornl.gov.
authors: Bing
authors: B
authors: Qi
authors: The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada. l.qian@utoronto.ca.
authors: Li
authors: L
authors: Qian