US 11,946,799 B2
Distributed fiber-optic acoustic sensing system and signal processing method using the same
Haiwen Cai, Shanghai (CN); Bin Lu, Shanghai (CN); Zhaoyong Wang, Shanghai (CN); Lei Ye, Shanghai (CN); Qing Ye, Shanghai (CN); and Ronghui Qu, Shanghai (CN)
Assigned to Shanghai Institute of Optics And Fine Mechanics, Chinese Academy of Sciences, Shanghai (CN)
Filed by Shanghai Institute of Optics And Fine Mechanics, Chinese Academy of Sciences, Shanghai (CN)
Filed on Jun. 7, 2021, as Appl. No. 17/340,529.
Application 17/340,529 is a continuation of application No. PCT/CN2020/092792, filed on May 28, 2020.
Claims priority of application No. 202010068189.3 (CN), filed on Jan. 21, 2020.
Prior Publication US 2021/0293612 A1, Sep. 23, 2021
Int. Cl. G01H 9/00 (2006.01); G01D 5/353 (2006.01)
CPC G01H 9/004 (2013.01) [G01D 5/35383 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A distributed fiber-optic acoustic sensing system, comprising
a distributed fiber-optic acoustic sensor comprising a plurality of sensing units along an axial direction, wherein the distributed fiber-optic acoustic sensor comprises
a distributed fiber-optic sensor based on a sweep frequency pulse and a pulse compression technology,
an optical frequency domain reflectometer, and
one or more of phase-sensitive optical time-domain reflectometers based on an ultra-narrow pulse or coherent detection, and
a sensing optical fiber,
wherein the distributed fiber-optic acoustic sensor is connected to the sensing optical fiber and is used for emitting a detection light pulse to the sensing optical fiber, collecting and demodulating sound fields of signal sources sensed along the sensing optical fiber;
a total number of the sensing units in the axial direction of the distributed fiber-optic acoustic sensor is L, the sensing units are divided into M subunits in the axial direction, and the number of the sensing units in each subunit is N, L=M×N, and the sensing units in each subunit are used for spatially coherent combination of sound field signals obtained by detection; and
spatial resolution of the distributed fiber-optic acoustic sensor is centimeter-level or higher.