相位敏感光时域反射系统数字正交解调算法分析及改进研究

对相位敏感光时域反射系统数字正交解调算法进行了研究。分析了正交解调算法中数字滤波器群延时对系统定位精度的影响, 提出采用重定位方法矫正定位误差; 同时, 研究了系统空间分辨率受正交解调算法中数字滤波器的影响, 并通过仿真和实验,验证并分析了上述问题。结果表明, 重定位方法可消除正交解调算法中数字滤波器造成的定位误差, 系统空间分辨率由系统结构与数字滤波器共同决定, 且由数字滤波器决定的空间分辨率随数字滤波器阶数的增加而增加。实验中解调选择112阶滤波器较佳。

Abstract

The digital quadrature demodulation algorithm of phase sensitive optical time domain reflectometer is investigated. The influence of the group delay of the digital filter in quadrature demodulation algorithm on the positioning accuracy is analyzed, and the relocation method is proposed to correct the positioning error. Meanwhile, the influences of the digital filter in the quadrature demodulation algorithm on the spatial resolution of the system is simulated and experimented. The results show that the relocation method can eliminate the positioning error caused by the digital filter in the quadrature demodulation algorithm. The spatial resolution of the system is determined by the system structure and the digital filter, and the spatial resolution of the digital filter improves with the increase of the order of the digital filter. In this experiment, the demodulation is appropriate to select 112 order filter.

参考文献

[1] 吕月兰, 行永伟. 相位光时域反射计瑞利散射波形特性研究［J］. 光学学报, 2011, 31(8): 0819001.

Lü Yuelan, Xing Yongwei. Investigation on rayleigh scattering waveform in phase optical time domain reflectometer［J］. Acta Optica Sinica, 2011,31(8): 0819001.

[2] He H J, Shao L Y, Li Z L, et al. Self-mixing demodulation for coherent phase-sensitive OTDR system［J］. Sensors, 2016, 16(5): 681-691.

[3] Wang Z N, Zhang L, Wang S, et al. Coherent φ-OTDR based on I/Q demodulation and homodyne detection［J］. Optics Express, 2016, 24(2): 853-858.

[4] Martins H F, Martin-Lopez S, Corredera P, et al. Phase-sensitive optical time domain reflectometer assisted by first-order Raman amplification for distributed vibration sensing over >100 km［J］. Journal of Lightwave Technology, 2014, 32(8): 1510-1518.

[5] Tayler H F, Lee C E. Apparatus and method for fiber optic intrusion sensing: 5194847［P］. 1993-3-16.

[6] Li Y, Zhou Y, Zhang L, et al. Phase-sensitive optical time-domain reflectometry amplified by gated Raman pump［J］. Photonic Sensors, 2015, 5(4): 345-450.

[7] 周俊, 潘政清, 叶青, 等. 基于多频率综合鉴别φ-OTDR 系统中干涉衰落假信号的相位解调技术［J］. 中国激光, 2013, 40(9): 0905003.

Zhou Jun, Pan Zhengqing, Ye Qing, et al. Phase demodulation technology using a multi-frequency source for discrimination of interference-fading induced false alarms in a φ-OTDR system［J］. Chinese J Lasers, 2013, 40(9): 0905003.

[8] Wang Z Y, Pan Z Q, Fang Z J, et al. Ultra-broadband phase-sensitive optical time-domain reflectometry with a temporally sequenced multi-frequency source［J］. Optics Letters, 2015, 40(22): 5192-5195.

[9] Zhang M, Wang S, Zheng Y W, et al. Enhancement for φ-OTDR performance by using narrow linewidth light source and signal processing［J］. Photonic Sensors, 2016, 6(1): 58-62.

[10] 梁可桢, 潘政清, 周俊, 等. 一种基于相位敏感光时域反射计的多参量振动传感器［J］. 中国激光, 2012, 39(8): 0805004.

Liang Kezhen, Pan Zhengqing, Zhou Jun, et al. Multi-parameter vibration detection system based on phase sensitive optical time domain reflectometer［J］. Chinese J Lasers, 2012, 39(8): 0805004.

[11] Pan Z Q, Liang K Z, Ye Q, et al. Phase-sensitive OTDR system based on digital coherent detection［C］. SPIE, 2011, 8311: 83110S.

[12] Pang F F, He M T, Liu H H, et al. A fading-discrimination method for distributed vibration sensor using coherent detection of φ-OTDR［J］. IEEE Photonics Technology Letters, 2016, 28(23): 2752-2755.

王旭, 刘珉含, 于淼, 常天英, 崔洪亮, 罗政纯, 付群健, 白杨. 相位敏感光时域反射系统数字正交解调算法分析及改进研究[J]. 中国激光, 2017, 44(12): 1210002. Wang Xu, Liu Minhan, Yu Miao, Chang Tianying, Cui Hongliang, Luo Zhengchun, Fu Qunjian, Bai Yang. Analysis and Improvement for Digital Quadrature Demodulation Algorithm on Phase-Sensitive Optical Time-Domain Reflectometric System[J]. Chinese Journal of Lasers, 2017, 44(12): 1210002.

相位敏感光时域反射系统数字正交解调算法分析及改进研究

关于本站 Cookie 的使用提示

全站搜索

相位敏感光时域反射系统数字正交解调算法分析及改进研究

相关论文

相关资讯

关于本站 Cookie 的使用提示

全站搜索