TDM- AND WDM-BASED FBG SENSOR ARRAY SYSTEM

摘要

In a TDM- and WDM-based FBG sensor array system, a source emits a light covering a selected wavelength range. The light is amplified and then used to generate a series of pulses that are fed into an array of sensor gratings. The propagation of a pulse through the sensor array results in a time-domain-multiplexed output, comprising a series of output pulses in which each output pulse comprises a reflection of the input pulse at a respective grating in the sensor array. Raman amplification is used to amplify both the pulse input into and the time-domain multiplexed output from the sensor array, which is then coupled into an output processing stage for receiving the sensor output and for reconstructing the wavelength output of each grating in the sensor array. The wavelength change for each grating is then used to calculate a physical parameter(s) to be measured, such as temperature and/or strain.

主权项

1. A fiber optic sensor system, comprising:
an input generator comprising a light source for emitting light covering a selected wavelength range, a rare-earth-doped fiber amplifier for amplifying the emitted light, and a modulator for modulating the emitted light to produce a series of light pulses; a sensor stage coupled to the input generator for receiving the series of light pulses as an input, and for transmitting the light pulses through an array of sensor gratings positioned along an optical pathway, wherein the propagation of a pulse through the sensor array results in a time-domain-multiplexed output, comprising a series of output pulses in which each output pulse comprises a reflection of the input pulse at a respective grating in the sensor array,
wherein the sensor stage comprises a Raman amplification means for amplifying both the input into the sensor array and the time-domain multiplexed output coming out of the sensor array; an output processing stage for detecting the output out of the sensor array and for reconstructing the wavelength output of each grating in the sensor array; and a control module for operating the system stages.