Fiber optical sensor demodulation research based on asymmetric 3×3 coupler
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摘要: 为了解决3×3耦合器相位解调中，输出的3路信号分光比不均匀和相位差不能严格满足120°的非对称问题，采用了一种新型的3×3耦合器解调方案，并进行了理论分析和实验验证。利用均值算法对输出的任意两路信号分别进行预处理，压缩原始3路输出信号之间的功率与相位的偏差，使经过矫正后新的3路信号近似为对称状态输出。根据仿真与实验的结果，分析了耦合器输出的对称性条件和新型解调方案的抗噪声能力。结果表明，该新型解调方案可以有效矫正3×3耦合器3路输出信号的非对称性，新方案的噪声水平约为10-4mW，信噪比约为50dB, 与传统的解调方案相比，可以得到准确度与信噪比更高的待测信号。这一结果对光纤相位解调领域有很好的指导作用，加速了光纤传感技术的实用化进程。Abstract: In the fiber optical sensor demodulation based on asymmetric 3×3 coupler, the fiber-optic median phase shift 3×3 adder due to the limitation of the manufacturing process and the susceptibility to external environmental interference, and then the three-way signal output has an uneven splitting ratio and an asymmetric phenomenon that the phase difference cannot meet 120°, which causes a problem that could not be accurately corrected. In order to solve these problems, a new 3×3 replacer was used, and theoretical analysis and experimental verification were performed. The mean two algorithms were used to pre-process any two signals output, and compressed the original three signals. The power and phase difference between the output signals of the two channels make the new three-channel signals after correction to be approximately symmetrical output, and then perform a symmetric algorithm operation. Simulation and experimental results show that the new scheme can effectively correct the asymmetry of the three output signals of the positive 3×3 converter, and classify it. Noise level of the new scheme is about 10-4mW and signal-to-noise ratio is about 50dB. Compared with the traditional alternative scheme, the new structure can obtain higher accuracy and signal-to-noise ratio of the signal under test. In addition, according to the simulation and experimental results, the symmetry conditions of the output of the replacer and the anti-noise capability of the new superposition scheme are analyzed. The result has a good guiding role in the field of optical fiber polarizers and accelerates the practical process of optical fiber sensing technology.
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Keywords:
- optoelectronics /
- phase demodulation /
- mean algorithm /
- 3×3 coupler
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Figure 3. Simulated Lissajous signal with a phase deviation of 8°
a—figures of Lissajous of the first and second channels b—figures of Lissajous of the first and third channels c—figures of Lissajous of the second and third channels
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Figure 4. A new demodulation scheme with a phase deviation of 8° simulates three Lissajous signals
a—figures of Lissajous of the first and second channels b—figures of Lissajous of the first and third channels c—figures of Lissajous of the second and third channels
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Figure 5. Figures of Lissajous formed by using three signals of traditional demodulation scheme
a—figures of Lissajous of the first and second channels b—figures of Lissajous of the first and third channels c—figures of Lissajous of the second and third channels
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Figure 6. The experimental results obtained by using the traditional demodulation scheme
a—time domain signal diagram b—frequency domain signal diagram
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Figure 7. Figures of Lissajous formed by using three signals of the new demodulation scheme
a—figures of Lissajous of the first and second channels b—figures of Lissajous of the first and third channels c—figures of Lissajous of the second and third channels
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[1] LU Y, ZHU T, CHENG L, et al. Distributed vibration sensor based on coherent detection of phase-OTDR[J]. Journal of Lightwave Technology, 2010, 28(22): 3243-3249. http://www.opticsinfobase.org/JLT/abstract.cfm?uri=JLT-28-22-3243
[2] PENG F, DUAN N, RAO Y, et al. Real-time position and speed monitoring of trains using phase-sensitive OTDR[J]. IEEE Photonics Technology Letters, 2014, 26(20): 2055-2057. DOI: 10.1109/LPT.2014.2346760
[3] ZHANG B, ZHANG E T, HU X Ch, et al. Amplification charactcristics of multiwavelength crbium-doped fiber laser amplifiers[J]. Laser Technology, 2018, 42(3): 325-330(in Chinese). http://www.zhangqiaokeyan.com/academic-journal-cn_laser-technology_thesis/0201236224191.html
[4] BAO X, ZHOU D P, BAKER C, et al. Recent development in the distributed fiber optic vibration and ultrasonic detection[J]. Journal of Lightwave Technology, 2016, 35(16): 3256-3267. http://ieeexplore.ieee.org/document/7572132
[5] LIU Sh, HAN X Y, XIONG Y Ch. Distributed vibration detection system based on weak fiber grating array[J]. Chinese Journal of Lasers, 2017, 44(2): 0210001(in Chinese). http://en.cnki.com.cn/Article_en/CJFDTotal-JJZZ201702035.htm
[6] YING C. Quantitative detection of phase-demodulation techniques for phase-sensitive optical time domain reflectometry[D]. Hangzhou: Zhejiang University, 2018: 13-23(in Chinese).
[7] ZHANG X, SUN Z, SHAN Y, et al. A high performance distributed optical fiber sensor based on φ-OTDR for dynamic strain measurement[J]. IEEE Photonics Journal, 2017, 9(3): 1-12. http://ieeexplore.ieee.org/document/7917232
[8] XU N, DAI M. Distributed optical fiber temperature and pressure sensor design[J]. Chinese Optics, 2015, 8(4): 629-635(in Chinese).
[9] LIU L. Research on light reflector based on helium pulse[D]. Shanghai: Shanghai Jiao Tong University, 2015: 17-47(in Chinese).
[10] WU G X, DUAN F J. Avalanche photodiode electric heterodyne mixing technology and its parameter optimization[J]. Laser Technology, 2015, 39(6):803-804(in Chinese). http://www.opticsjournal.net/abstract.htm?id=OJ151130000300VsYu25
[11] QIAO J P, DENG L W, HE J, et al. Optimization of fast image encryption algorithm based on chaotic mapping[J]. Laser Technology, 2017, 41(6): 897-903(in Chinese). http://en.cnki.com.cn/Article_en/CJFDTotal-JGJS201706026.htm
[12] XU G, HE Ch Ch, ZHANG L N, et al. Research of position technology of Mach-Zehnder interferometer[J]. Laser Technology, 2019, 43(2): 195-200(in Chinese).
[13] SU B L. Investigation on quasi-lossless transmission system based on pumping Raman amplification[J]. Laser Technology, 2017, 41(2): 265-269(in Chinese). http://en.cnki.com.cn/Article_en/CJFDTotal-JGJS201702024.htm
[14] QIAN X L, KONG Y, DU T Y, et al. Study on full-sensitivity to vibration of phase sensitive optical time-domain reflectometers[J].Laser Technology, 2019, 43(5): 608-613(in Chinese). http://en.cnki.com.cn/Article_en/CJFDTotal-JGJS201905004.htm
[15] CHEN K, ZHENG J Y, ZHOU J H, et al. Design of real-time fast polarization control algorithm[J]. Laser Technology, 2017, 41(5): 738-742(in Chinese). http://en.cnki.com.cn/Article_en/CJFDTotal-JGJS201705024.htm
[16] KOYAMADA Y, IMAHAMA M, KUBOTA K, et al. Fiber-optic distributed strain and temperature sensing with very high measurand resolution over long range using coherent OTDR[J]. Journal of Lightwave Technology, 2009, 27(9): 1142-1146. http://www.osapublishing.org/jlt/abstract.cfm?uri=jlt-27-9-1142
[17] LV Y L, XING Y W. Study on rayleigh scattering waveform characteristics of phase light time domain reflectometer[J]. Acta Optica Sinica, 2011, 31(8): 0819001(in Chinese). http://en.cnki.com.cn/Article_en/CJFDTOTAL-GXXB201108042.htm
[18] HUANG Zh H, WANG Y L, LI G F, et al. Adaptive frequency-domain equalization for few-mode fiber transmission systems[J]. Laser Technology, 2017, 41(1): 124-128(in Chinese). http://www.jgjs.net.cn/EN/Y2017/V41/I1/124
[19] GAO H, LIU J M, YANG Ch, et al. Compact solid-state lasers with high peak power used for remote laser rangefinders[J]. Laser Technology, 2019, 43(5): 597-600(in Chinese). http://en.cnki.com.cn/Article_en/CJFDTotal-JGJS201905002.htm
[20] XU S H, XIAO Sh L. Research on reverse modulation optical communication system based on acousto-optic modulation[J]. Laser Technology, 2015, 39(5): 599-600(in Chinese). http://en.cnki.com.cn/Article_en/CJFDTotal-JGJS201505004.htm
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