scholarly journals Prevention of false peak detection of Brillouin gain spectrum by using peak tracking and trend analysis

2020 ◽  
Vol 103 (1-4) ◽  
pp. 3-9
Author(s):  
Osamu Furukawa
Keyword(s):  
Trend Analysis ◽  
Peak Detection ◽  
Gain Spectrum ◽  
Peak Tracking ◽  
Brillouin Gain ◽  
False Peak

scholarly journals Measurement Improvement of Distributed Optical Fiber Sensor via Lorenz Local Single Peak Fitting Algorithm

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1166
Author(s):  
Bin Liu ◽  
Jianping He ◽  
Shihai Zhang ◽  
Yinping Zhang ◽  
Jianan Yu ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Frequency Shift ◽  
Optical Fiber Sensor ◽  
Gain Spectrum ◽  
Fiber Sensor ◽  
Peak Fitting ◽  
Fitting Algorithm ◽  
Distributed Optical Fiber Sensor ◽  
Brillouin Gain ◽  
Distributed Optical Fiber

Brillouin frequency shift (BFS) of distributed optical fiber sensor is extracted from the Brillouin gain spectrum (BGS), which is often characterized by Lorenz type. However, in the case of complex stress and optical fiber self damage, the BGS will deviate from Lorenz type and be asymmetric, which leads to the extraction error of BFS. In order to enhance the extraction accuracy of BFS, the Lorenz local single peak fitting algorithm was developed to fit the Brillouin gain spectrum curve, which can make the BSG symmetrical with respect to the Brillouin center frequency shift. One temperature test of a fiber-reinforced polymer (FRP) packaged sensor whose BSG curve is asymmetric was conducted to verify the idea. The results show that the local region curve of BSG processed by the developed algorithm has good symmetry, and the temperature measurement accuracy obtained by the developed algorithm is higher than that directly measured by demodulation equipment. Comparison with the reference temperature, the relative measurement error measured by the developed algorithm and BOTDA are within 4% and 8%, respectively.

Simulating and Designing Brillouin Gain Spectrum in Single-Mode Fibers

2004 ◽  
Vol 22 (2) ◽  
pp. 631-639 ◽  
Author(s):  
Y. Koyamada ◽  
S. Sato ◽  
S. Nakamura ◽  
H. Sotobayashi ◽  
W. Chujo
Keyword(s):  
Single Mode ◽  
Gain Spectrum ◽  
Brillouin Gain

scholarly journals Fast Measurement of Brillouin Frequency Shift in Optical Fiber Based on a Novel Feedforward Neural Network

Photonics ◽  
2021 ◽  
Vol 8 (11) ◽  
pp. 474
Author(s):  
Fen Xiao ◽  
Mingxing Lv ◽  
Xinwan Li
Keyword(s):  
Neural Network ◽  
Optical Fiber ◽  
Frequency Shift ◽  
Brillouin Scattering ◽  
Principal Component ◽  
Feedforward Neural Network ◽  
Gain Spectrum ◽  
Fiber Sensors ◽  
Brillouin Gain ◽  
Distributed Optical Fiber

Brillouin scattering-based distributed optical fiber sensors have been successfully employed in various applications in recent decades, because of benefits such as small size, light weight, electromagnetic immunity, and continuous monitoring of temperature and strain. However, the data processing requirements for the Brillouin Gain Spectrum (BGS) restrict further improvement of monitoring performance and limit the application of real-time measurements. Studies using Feedforward Neural Network (FNN) to measure Brillouin Frequency Shift (BFS) have been performed in recent years to validate the possibility of improving measurement performance. In this work, a novel FNN that is 3 times faster than previous FNNs is proposed to improve BFS measurement performance. More specifically, after the original Brillouin Gain Spectrum (BGS) is preprocessed by Principal Component Analysis (PCA), the data are fed into the Feedforward Neural Network (FNN) to predict BFS.

Distributed temperature and strain measurement based on Brillouin gain spectrum and Brillouin beat spectrum

2021 ◽  
pp. 1-1
Author(s):  
Jianqin Peng ◽  
Yuangang Lu ◽  
Zelin Zhang ◽  
Zhengnan Wu ◽  
Yuyang Zhang
Keyword(s):  
Strain Measurement ◽  
Gain Spectrum ◽  
Brillouin Gain

Brillouin gain spectrum characterization in Ge-doped large-mode-area fibers

2021 ◽  
Author(s):  
Xia-Xia Niu ◽  
Yi-Feng Yang ◽  
Zhao Quan ◽  
Chun-Lei Yu ◽  
Qin-Ling Zhou ◽  
...  
Keyword(s):  
Gain Spectrum ◽  
Large Mode Area ◽  
Brillouin Gain ◽  
Mode Area

scholarly journals Stimulated Brillouin Scattering Enhanced Fibers for Narrow-Band Filtering by Tailoring Brillouin Gain Spectrum

2017 ◽  
Vol 9 (6) ◽  
pp. 1-11
Author(s):  
Zhen Guo ◽  
Changjian Ke ◽  
Chen Xing ◽  
Yibo Zhong ◽  
Guo Yin ◽  
...  
Keyword(s):  
Narrow Band ◽  
Brillouin Scattering ◽  
Stimulated Brillouin Scattering ◽  
Gain Spectrum ◽  
Brillouin Gain ◽  
Stimulated Brillouin

scholarly journals The Influence of Laser Linewidth on the Brillouin Shift Frequency Accuracy of BOTDR

2018 ◽  
Vol 9 (1) ◽  
pp. 58 ◽  
Author(s):  
Qing Bai ◽  
Min Yan ◽  
Bo Xue ◽  
Yan Gao ◽  
Dong Wang ◽  
...  
Keyword(s):  
Probe Pulse ◽  
Measurement Accuracy ◽  
Signal To Noise Ratio ◽  
Gain Spectrum ◽  
Laser Source ◽  
Laser Linewidth ◽  
Optical Time Domain Reflectometer ◽  
Brillouin Gain ◽  
Optical Time ◽  
Shift Frequency

This paper analyzes the influence of laser linewidth on the measurement accuracy of a frequency-scanning Brillouin optical time domain reflectometer (FS-BOTDR), allowing for both the width of Brillouin gain spectrum and the signal-to-noise ratio (SNR) of the BOTDR system. The measurement accuracy of the Brillouin frequency shift (BFS) is theoretically investigated versus the duration of the probe pulse and the linewidth of the laser source, by numerically simulating how a FS-BOTDR works and evaluating the Brillouin gain spectrum (BGS) width and the system SNR. The simulation results show that the BFS accuracy is improved as the laser linewidth becomes narrower when the probe pulse width is fixed. We utilize five types of lasers with respective linewidths of 1.05 MHz, 101 kHz, 10.2 kHz, 3.1 kHz, and 98 Hz to compare the BFS measurement accuracy over a ~10 km optical sensing fiber. The experimental results demonstrate that the root-mean-square error (RMSE) of BFS decreases with the laser linewidth narrowing from 1.05 MHz to 3.1 kHz, which is in good agreement with the numerical simulation. However, the RMSE of BFS increases when the laser linewidth is less than 3.1 kHz, which may arise from the coherent Rayleigh noise due to a too narrow laser linewidth. The results can provide a theoretical basis and experimental guidance for choosing the appropriate laser linewidth in BOTDR.

Sign in / Sign up

Export Citation Format

Share Document