基于长周期光纤光栅线性边缘滤波的地震波解调系统  

Seismic wave interrogation system based on the linear edge filter chracteristics of long period fiber grating

作　　者：周锐[1] 乔学光[1,2] 王若晖[1] 高宏[1] 杨扬[1] 张敬花[1] 

机构地区：[1]西北大学,陕西西安710069 [2]西安石油大学光电油气测井与检测教育部重点实验室,陕西西安710065

出　　处：《光电子．激光》2011年第7期987-991,共5页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金资助项目(60727004;61077060);国家"863"计划资助项目(2007AA03Z413;2009AA06Z203);科技部国际科技合作资助项目(2008CR1063);教育部科技创新工程重大项目(Z08119);陕西省重大科技创新项目(2009ZKC01-19;2008ZDGC-14);西北大学研究生创新教育资助项目(09YZZ53)

摘　　要：设计一种针对地震波信号的解调系统,讨论了长周期光纤光栅(LPFG)制作时参数的控制方法,选用边缘特性良好的LPFG做线性边缘滤波器,在1 550.35~1 553.14 nm间具有0.998 96的线性拟合度,功率灵敏度达1.692 dBm/nm。在信号处理中,采用参考光路与滤波光路比较,消除本底信号的影响;利用LabVIEW软件代替部分硬件,并作为信号采集及信号分析处理功能模块,使系统解调检测波长灵敏度达到1.13 pm/mV,在低频段(2~150 Hz),动态分辨率为0.08 pm/(Hz)^(1/2),动态范围为50~60 dB。本文解调系统操作简单、灵敏度高、稳定性好、性价比高且响应速度快,可以用于地震勘探。In the interrogation system designed for seismic sensing,the parameter control of long period fiber grating（LPFG） during fabrication is discussed,and the LPFG is employed as a linear edge filter because of its high slope efficiency of 0.998 96 from 1 550.35 nm to 1 553.14 nm and power sensitivity of 1.692 dBm/nm.The background noise is eliminated by comparing the reference signal with the filtered signal.LabVIEW is used as processing function module to acquire and analyze data.The sensitivity of detecting wavelength can reach over 1.13 pm/mV（2-150 Hz in frequency domain）,the dynamic range is 50-60 dB,and the resolution can reach 0.08 pm/Hz）^（1/2）.The results show that this interrogation system has high sensitivity,good stability,and fast speed,and it can be used for seismic exploration.

关 键 词：光纤地震波勘探 信号解调 长周期光纤光栅(LPFG) 边缘滤波 

分 类 号：TN253[电子电信—物理电子学]