Optical Fiber Temperature Measurement Signal Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Optical fiber temperature distribution measurement devices using code modulation, such as Golay code, face inaccuracies due to deviations at temperature and loss variation points, especially when the light source and driving circuit features are temperature-dependent, leading to measurement errors.
Innovation Solution
A storage system that corrects deviations in measured signals using pre-stored correction data, which is used by a corrector to adjust demodulated signals from the optical fiber temperature distribution measurement device, improving measurement accuracy by accounting for temperature variations and loss changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If code modulation using Golay code is performed for the train of light pulses to improve dynamic range, then measurement dynamic range is improved, but measurement accuracy degrades at temperature variation points and loss variation points due to deviation in the measured signal
Solution Approach 1:
The patent applies preliminary action by pre-storing correction data that compensates for deviations in the measured signal at temperature variation points and loss variation points. This correction data is prepared in advance and applied during the measurement process to eliminate accuracy degradation caused by code modulation, thereby resolving the contradiction between improved dynamic range and degraded measurement precision.
Solution Approach 2:
The patent implements feedback by using the stored correction data to adjust and correct the measured signal. The correction data provides feedback information that compensates for the deviation introduced by code modulation, allowing the system to maintain high measurement accuracy while benefiting from the extended dynamic range provided by Golay code modulation.
2Measurement precision
If correction data is stored and used to correct measured signals, then measurement accuracy is improved, but device complexity increases due to additional storage and correction components
Solution Approach 1:
The patent applies copying by creating and storing correction data that replicates the expected deviation pattern in the measured signal. This correction data is a simplified representation of the deviation characteristics, which can be easily stored and applied without requiring complex real-time calculation systems, thereby improving measurement accuracy while minimizing the increase in device complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively corrects temperature and loss-related deviations, enhancing the accuracy of temperature distribution measurements along the optical fiber by using stored correction data to refine the demodulated signals, thereby improving measurement precision.
Implementation Method 1
measure a temperature distribution along a longitudinal direction of the optical fiber by measuring Raman back scattering light (Stokes light and anti-Stokes light) generated in the optical fiber
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
An optical fiber temperature distribution measurement device for measuring a temperature distribution along a longitudinal direction of an optical fiber is provided. The device includes: a light transmitter configured to input a train of code-modulated light pulses into the optical fiber; a light receiver configured to receive Raman back scattering lights generated by inputting the train of code-modulated light pulses into the optical fiber; a demodulator configured to perform a correlation processing between a measured signal output from the light receiver and a code string associated with a type of the code modulation performed by the light transmitter, and to demodulate the measured signal; a storage storing a correction data to be used to correct a distortion of the measured signal output from the light receiver when an impulsive pulsed light is output from the light transmitter; and a corrector configured to perform a correction to one of the measured signal output from the light receiver and a demodulated signal output from the demodulator, using the correction data stored in the storage.