Zahoor, R.; Vallifuoco, R.; Zeni, L.; Minardo, A. Distributed Temperature Sensing through Network Analysis Frequency-Domain Reflectometry. Sensors2024, 24, 2378.
Zahoor, R.; Vallifuoco, R.; Zeni, L.; Minardo, A. Distributed Temperature Sensing through Network Analysis Frequency-Domain Reflectometry. Sensors 2024, 24, 2378.
Zahoor, R.; Vallifuoco, R.; Zeni, L.; Minardo, A. Distributed Temperature Sensing through Network Analysis Frequency-Domain Reflectometry. Sensors2024, 24, 2378.
Zahoor, R.; Vallifuoco, R.; Zeni, L.; Minardo, A. Distributed Temperature Sensing through Network Analysis Frequency-Domain Reflectometry. Sensors 2024, 24, 2378.
Abstract
In this paper, we propose and demonstrate a network analysis optical frequency domain reflectometer (NA-OFDR) for distributed temperature measurements at high spatial (down to 3 cm) and temperature resolution. The system makes use of a frequency-stepped, continuous-wave (cw) laser, whose output light is modulated using a vector network analyzer. The latter is also used to demodulate the amplitude of the beat signal obtained by coherently mixing the Rayleigh backscattered light with a local oscillator. The system is capable of high measurand resolution (50 mK at 3-cm spatial resolution), thanks to the high sensitivity of coherent Rayleigh scattering to temperature. Furthermore, compared to the conventional optical-frequency domain reflectometry (OFDR), the proposed system does not rely on the use of a tunable laser, therefore it is less prone to limitations related to the laser coherence or sweep nonlinearity. Two configurations are analyzed, both numerically and experimentally, based on either a double sideband or single sideband modulated probe light. The results confirm the validity of the proposed approach.
Keywords
Distributed temperature sensing; Rayleigh scattering; Optical Frequency-Domain Reflectometry.
Subject
Engineering, Electrical and Electronic Engineering
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
