A Fiber-Optic Interferometric Tri-Component Geophone for Ocean Floor Seismic Monitoring

Jiandong Chen; Tianying Chang; Qunjian Fu; Jinpeng Lang; Wenzhi Gao; Zhongmin Wang; Miao Yu; Yanbo Zhang; Hong-Liang Cui

doi:10.3390/s17010047

A Fiber-Optic Interferometric Tri-Component Geophone for Ocean Floor Seismic Monitoring

Sensors (Basel). 2016 Dec 28;17(1):47. doi: 10.3390/s17010047.

Authors

Jiandong Chen¹, Tianying Chang^{2

3}, Qunjian Fu⁴, Jinpeng Lang⁵, Wenzhi Gao⁶, Zhongmin Wang⁷, Miao Yu⁸, Yanbo Zhang⁹, Hong-Liang Cui¹⁰

Affiliations

¹ College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China. chenjd13@mails.jlu.edu.cn.
² College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China. tchang@jlu.edu.cn.
³ Institute of Automation, Shandong Academy of Sciences, Jinan 250014, China. tchang@jlu.edu.cn.
⁴ College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China. fuqj16@mails.jlu.edu.cn.
⁵ College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China. langjp14@mails.jlu.edu.cn.
⁶ College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China. gaowz15@mails.jlu.edu.cn.
⁷ Institute of Automation, Shandong Academy of Sciences, Jinan 250014, China. gezhb@sdas.org.
⁸ College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China. miaoyu14@mails.jlu.edu.cn.
⁹ Institute of Automation, Shandong Academy of Sciences, Jinan 250014, China. zhangyb@sdas.org.
¹⁰ College of Instrumentation & Electrical Engineering, Jilin University, Changchun 130061, China. hcui@jlu.edu.cn.

Abstract

For the implementation of an all fiber observation network for submarine seismic monitoring, a tri-component geophone based on Michelson interferometry is proposed and tested. A compliant cylinder-based sensor head is analyzed with finite element method and tested. The operation frequency ranges from 2 Hz to 150 Hz for acceleration detection, employing a phase generated carrier demodulation scheme, with a responsivity above 50 dB re rad/g for the whole frequency range. The transverse suppression ratio is about 30 dB. The system noise at low frequency originated mainly from the 1/f fluctuation, with an average system noise level -123.55 dB re rad / Hz ranging from 0 Hz to 500 Hz. The minimum detectable acceleration is about 2 ng / Hz , and the dynamic range is above 116 dB.

Keywords: fiber optic Michelson interferometer; geophone; phase generated carrier; vibration sensor.