Device, method and system for quantifying a change in environmental conditions along the length of an optical fiber
AssigneeBundesrepublik Deutschland, vertreten durch den Bundesminister für Wirtschaft und Klimaschutz
InventorXin Lu
Life of this patent
Estimating the term…
Abstract
A device (100) for quantifying a change in environmental conditions along the length of an optical fiber (130) includes a frequency-scanning optical pulse generator (110) to generate pulse sequences of optical pulses; an optical component (120) coupled with the pulse generator (110) to inject the optical pulses into an optical fiber (130) and to redirect the backscattered optical signal from the optical fiber (130); and a receiver module (150) coupled with the optical component (120). The receiver module (150) includes an interferometer (170) for determining phase information of the backscattered optical signal as a function of time and optical frequency.
Claims20
A device for quantifying a change in environmental conditions along the length of an optical fiber, comprising:
- a frequency-scanning optical pulse generator configured to generate pulse sequences of optical pulses with variable optical frequencies;
- an optical component coupled with the frequency-scanning optical pulse generator for injecting the optical pulses into an optical fiber and for redirecting the backscattered optical signal from the optical fiber;
- and
- a receiver module coupled with the optical component, the receiver module including
- an interferometer and photo detectors, the interferometer having an input for receiving the backscattered optical signal and a coupler for providing optical signal outputs with shifted phases, wherein each optical signal output of the coupler is coupled with one of the photo detectors for providing electrical signals;
- and
- a data processing device coupled with the photo detectors for receiving the electrical signals, the data processing device being configured to derive phase information of the backscattered optical signal from the electrical signals as a function of time and optical frequency.
A system for quantifying a change in environmental conditions along the length of an optical fiber, comprising:
- a device for quantifying a change in environmental conditions along the length of an optical fiber, the device including:
- a frequency-scanning optical pulse generator configured to generate pulse sequences of optical pulses with variable optical frequencies;
- an optical component coupled with the frequency-scanning optical pulse generator for injecting the optical pulses into an optical fiber and for redirecting the backscattered optical signal from the optical fiber;
- and
- a receiver module coupled with the optical component, the receiver module including
- an interferometer and photo detectors, the interferometer having an input for receiving the backscattered optical signal and a coupler for providing optical signal outputs with shifted phases, wherein each optical signal output of the coupler is coupled with one of the photo detectors for providing electrical signals;
- and
- a data processing device coupled with the photo detectors for receiving the electrical signals, the data processing device being configured to derive phase information of the backscattered optical signal from the electrical signals as a function of time and optical frequency, and
- an optical fiber coupled with the optical component of the device.
A method for determining changes of parameters of interest along an optical fiber for low and high frequency measurement, the method comprising the steps of:
- providing optical pulses of different optical frequencies;
- injecting the optical pulses into an optical fiber;
- receiving an optical signal Rayleigh backscattered from the optical fiber;
- splitting the optical signal into two optical split signals;
- detecting one of the two optical split signals as intensity of the backscattered optical signal as a function of time to obtain reflection spectra along the optical fiber;
- introducing the other of the two optical signals into an interferometer and detecting the output of the interferometer as a phase of the optical signal backscattered from the optical fiber as a function of time;
- and
- calculating a spectral frequency based on correlation of the reflection spectrum along the optical fiber for low frequency measurement and a phase difference based on the output of the interferometer for high frequency measurement.
18-21. (canceled)
Dependencies are inferred from the claim text.