Quadrature Operating Point Stabilizing Technique for Fiber-Optic Fabry-Perot Sensors Using Vernier-Tuned Distributed Bragg Reflectors Laser

Ang Li, Zhenguo Jing, Yueying Liu, Qiang Liu, Zhiyuan Huang, Yang Cheung, Yang Zhang, Ming Han, Wei Peng

Research output: Contribution to journalArticlepeer-review

6 Scopus citations

Abstract

Drift of Quadrature operating point (Q-point) due to variations in ambient temperature restricts the demodulation accuracy of fiber-optic extrinsic Fabry-Perot interferometer (EFPI) sensors. To overcome this challenge, in this paper, we propose and demonstrate a self-stabilizing Q-point system based on Vernier-tuned distributed Bragg reflectors (VT-DBR) laser, the laser wavelength is locked to a point with the maximum slope on the interference spectrum of fiber-optic EFPI sensor. Taking advantage of large-tuning range (40nm) and fast wavelength switching capability (<20ns), we develop a robust EFPI acoustic sensor system with stable Q-point operation. When the EFPI sensor is subject to ambient temperature variations, we use an FPGA to implement the fast laser wavelength switching of the laser and automatic Q-point locking that ensure Q-point stability. The operating point drift from Q-point is obtained by dc voltage output changes. Experimental results indicate that stabilizing Q-point of the EFPI sensor is effectively realized during the temperature changes between 27-32°C. Without the stabilization method, the deviation is up to 85.5% of dc voltage output at operating point from Q-point value. With the stabilization method, the deviation is less than 0.68%. This self-stabilizing Q-point method based on VT-DBR laser has a strong ability to resist ambient temperature variations, and provides a novel solution to Q-point drift of fiber-optic EFPI sensors.

Original languageEnglish (US)
Article number9169674
Pages (from-to)2084-2091
Number of pages8
JournalIEEE Sensors Journal
Volume21
Issue number2
DOIs
StatePublished - Jan 15 2021
Externally publishedYes

Keywords

  • Fabry-Perot interferometer
  • Q-point
  • VT-DBR laser
  • acoustic sensing system

ASJC Scopus subject areas

  • Instrumentation
  • Electrical and Electronic Engineering

Fingerprint

Dive into the research topics of 'Quadrature Operating Point Stabilizing Technique for Fiber-Optic Fabry-Perot Sensors Using Vernier-Tuned Distributed Bragg Reflectors Laser'. Together they form a unique fingerprint.

Cite this