Abstract
The frequency-modulated continuous-wave (FMCW) technique, which was originally investigated in radar technology, has been successfully used to construct various fiber-optic interferometers or sensors [1-3]. The advantages of this technology include compact and low-power laser sources, no ambiguous-fringe-counting problems, absolute measurement and simple signal processing. The application of the FMCW technique to rotation sensing has also been proposed by B. Culshaw et al [4]. They employ a heterodyne arrangement consisting of two independent Mach-Zehnder interferometers to sense the rotation speed. The limitation of such configuration is that the length of the fiber coil largely depends on the coherence length of the light source, because the fiber coil is employed as one of the arms of the Mach-Zehnder interferometers. For the available single-mode laser diode, for example, the coherence length is about 10 meters; and therefore, the maximum length of the fiber coil is limited to around 10 meters. This, of course, hardly provides enough rotation sensitivity for navigational applications.
© 2003 Optical Society of America
PDF ArticleMore Like This
Jesse Zheng
CThII3 Conference on Lasers and Electro-Optics (CLEO:S&I) 2004
Jesse Zheng
FWO7 Frontiers in Optics (FiO) 2005
Jesse Zheng
FTuA4 Frontiers in Optics (FiO) 2007