第20卷第3期 2012年3月
文章编号
1004-924X(2012)03-0468-09
光学精密工程
Optics and Precision Engineering
双Mach-Zehnder光纤干涉传感系统中
的偏振衰落控制
曾周末，张溪默*，封皓，靳世久，安阳
（天津大学精密测试技术及仪器国家重点实验室，天津300072）
Vol.20No.3
Mar.2012
摘要：针对偏振衰落现象导致信号关联的二义性使分布式双Mach-Zehnder光纤干涉传感系统难以实现高精度定位的向题，提出了一种控制偏振衰落的方法来保持系统检测信号的稳定性。利用系统的偏振模型分析了偏振衰落的来源，指出
偏振态、搜索偏振态工作点的抗偏振衰落思想。在此基础上通过分析输人偏振态的两个参量对信号相关系数的作用进一步明确了偏振控制对算法的要求，并利用模拟退火算法进行了验证。现场实验表明，该算法可快速搜索偏振态工作点，持续稳定系统检测信号的相关性；结果证实了提出的偏振衰落控制方法可行且有效，
词：相干光学；Mach-Zehnder干涉仅；干沙传感；偏振衰落；偏振控制；相关系数；模拟退火算法
键关
中图分类号：TH744.3;O436.3
文献标识码：A
doi;10.3788/OPE.20122003.0468
ControlofpolarizationfadingfordualMach-Zehnderfiber
interferometricsensingsystem
ZENG Zhou-mo,ZHANG Xi-mo',FENG Hao,JIN Shi-jiu,AN Yang(StateKeyLaboratory ofPrecisionMeasuringTechnologyand Instruments,
TianjinUniversity,Tianjin 300072,China)
*Correspondingauthor，E-mail：zxm2514@163.com
Abstract: In a dual Mach-Zehnder fiber interferometric sensing system, the high locating accuracy is hardly obtained due to the discrepancy of two detection signals resulting from polarization fading. To keep the stability of the detection signals, a method to control the polarization fading was proposed in this paper. A optical polarization model was established to analyze the origin of polarization fading in the system. It points out that the basic reason for the discrepancy of the detection signal correlation is from that the inconsistency of the polarization characteristics between two sensing fibers results in the effect of the input polarization on detection signals. Based on the analysis, the solutions of controlling the input polarization and searching for the working points of polarization state were put forward to e liminate the polarization fading.Furthermore,the requirements of polarization control were further determined by analyzing the relation between signal correlation coefficients and two parameters of in
收稿日期：2011-08-26；修订日期：2011-10-27.
基金项目：国家自然科学基金资助项目（No.60974110)；国家教育部博士点基金资助项目（No.200800560020）