Affiliation:
1. Nanjing Normal University
Abstract
We propose a time and wavelength division multiplexing (TWDM)-assisted passive quadrature phase demodulation mechanism in this Letter. Combining wavelength division multiplexers (WDMs) with a programmable modulated grating Y-branch (MG-Y) laser, this method realizes both fast switching of discrete wavelengths and fast activation of multiple sensing paths simultaneously. Deploying it on a fiber-optic dual-cavity Fabry–Perot (F-P) ultrasound sensor array, we achieve high-precision localization of partial discharge (PD) signal sources in a two-dimensional (2D) plane with a maximum distance error of 1.53 cm and a maximum angle error of about 3.02°. This demodulation scheme can balance the relationship between sensitivity, sampling rate, and time-delay-induced errors, and provides an innovative solution for high-frequency phase demodulation applications of sensor arrays, which is especially significant for high-frequency detection in specific environments like partial discharges, industrial nondestructive testing, and so on.
Funder
National Natural Science Foundation of China
Fundamental Research Funds for the Central Universities
Subject
Atomic and Molecular Physics, and Optics