Interrogation of a Dual-Fiber-Bragg-Grating Sensor Using an Arrayed Waveguide Grating

• Published in: IEEE transactions on instrumentation and measurement Vol. 56; no. 6; pp. 2641 - 2645
• Main Authors: Robertson, D., Niewczas, P., McDonald, J.R.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-12-2007; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Arrayed waveguide gratings; Arrayed waveguide gratings (AWGs); Bandwidth; Bragg gratings; Error detection; fiber Bragg gratings (FBGs); Fiber gratings; Fibers; Filters; Instrumentation; Interrogation; Optical fiber sensors; Photodetectors; Sensor arrays; sensor interrogation; Sensors; Signal processing; Solid state circuits; Strain measurement; strain sensors; Waveguides; Wavelengths
• ISSN: 0018-9456; 1557-9662
• DOI: 10.1109/TIM.2007.908156

In this paper, we consider the possibility of improving the accuracy of a solid-state fiber Bragg grating (FBG) interrogation system by using two, instead of one, FBGs inscribed on the same location of the fiber, with a small difference in the peak wavelength that each reflects. Signal processing can be applied to the outputs of the photodetectors that are connected to an arrayed waveguide grating to provide a linear response from the sensor. We demonstrate here that this method reduces errors when compared to the setup employing a single FBG with the same bandwidth as the dual sensor.