Distributed Fiber Optic Interferometric Geophone System Based on Draw Tower Gratings

• 来源期刊: 光子传感器（英文版）
• 关键词: Fiber optic sensing vibrating sensing draw tower grating interferometric geophone
• 年，卷（期）: 2017,（3）
• 页码范围: 246-252
• 页数: 7页
• 语种: 英文
• DOI: 10.1007/s13320-017-0408-2

摘要

A distributed fiber optic interferometric geophone array based on draw tower grating (DTG) array is proposed.The DTG geophone array is made by the DTG array fabricated based on a near-contact exposure through a phase mask during the fiber drawing process.A distributed sensing system with 96 identical DTGs in an equal separation of 20 m and an unbalanced Michelson interferometer for vibration measurement has been experimentally validated compared with a moving-coil geophone.The experimental results indicate that the sensing system can linearly demodulate the phase shift.Compared with the moving coil geophone,the fiber optic sensing system based on DTG has higher signal-to-noise ratio at low frequency.