摘要
理论分析了基于白光干涉的保偏光纤偏振模式耦合检测原理,并以迈克尔逊干涉仪对保偏光纤的偏振耦合的耦合强度和耦合点的位置进行了测试。由于机械式扫描干涉仪和信号处理电路会受到环境干扰和各种噪声的影响,限制了系统偏振耦合检测的灵敏度,应用小波变换对检测信号进行了分析,采用软阈值方法降噪处理,有效地去除了各种干扰和噪声,提高了干涉信号的信噪比3.2dB,耦合强度测试灵敏度也相应地得到了提高,增强了测试系统检测微弱偏振耦合的能力。
The principle of the cross coupling in polarization maintaining fiber based on white-light interferometry is presented.The coupling intensity and coupling position are measured by using Michelson-interferometer.The sensitivity of detection system is limited by environmental disturbance and mixture noise in the course of scanning measurement of the mechanical interferometer and signal processing.A wavelet soft threshold denoising method is adopted to process the interference signals.And then the noises are strongly restrained and the signal-to-noise ratio of the output signal is improved about 3.2 dB.The sensitivity increases correspondingly,and the ability of detecting weak coupling is improved.
出处
《光学技术》
CAS
CSCD
北大核心
2011年第3期264-268,共5页
Optical Technique
基金
国家973计划项目(2010CB327806)
天津市高等学校科技发展基金计划项目(20080715)
关键词
偏振耦合
白光干涉
信噪比
小波变换
降噪
polarization coupling
white-light interferometry
signal-to-noise ratio
wavelet transform
denoising
