Page 19 - 《应用声学》2023年第6期

第 42 卷 第 6 期 Vol. 42, No. 6
2023 年 11 月 Journal of Applied Acoustics November, 2023

⋄ 研究报告 ⋄

光纤声传感反正切解调的采样率与信号幅度关系 ∗

安秉文 1,2 吴先梅 1,2† 张金英 3

(1 中国科学院声学研究所 声场声信息国家重点实验室 北京 100190)
(2 中国科学院大学 北京 100049)
(3 北京理工大学光电学院 北京 100081)

摘要：针对光纤光栅声传感系统反正切解调算法中采样率与声场幅度相关这一现象，计算分析了正弦声信号、
高斯脉冲声信号在 3 种不同反正切算法下幅度与采样率的关系，用脉冲声信号进行了实验验证，并从相位展开
方式的判据出发予以机理解释，以期望在应用前可根据声场、传感器灵敏度等选择恰当的采样率。数值计算和
实验结果表明，这 3 种方式需要的采样率均与信号幅度呈线性关系，分别需要一个声周期内采样点数为信号幅
度的 8 倍、4 倍和 2 倍。此外，还将 3 种方式与微分 -交叉相乘算法在软件计算时的实时性和计算精度进行了比
较，在满足采样率要求时三者均较微分 -交叉相乘算法的表现更佳。
关键词：光纤声传感；反正切解调；3 × 3 耦合器
中图法分类号: TB551; O426.9; TN247 文献标识码: A 文章编号: 1000-310X(2023)06-1129-10
DOI: 10.11684/j.issn.1000-310X.2023.06.003

Relationship between sampling rate and signal amplitude of arctangent

demodulation algorithm in optical fiber acoustic sensing system

AN Bingwen 1,2 WU Xianmei 1,2 ZHANG Jinying 3

(1 State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China)
(2 University of Chinese Academy of Sciences, Beijing 100049, China)
(3 School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China)

Abstract: Aiming at the phenomenon that the sampling rate is related to the amplitude of sound field
when using an arctangent algorithm, the quantitative relationship between the sampling rate and the signal
amplitude is studied by calculating and analyzing situations of sinusoidal signal and Gaussian pulse signal
under three different algorithms, which helps select an appropriate sampling rate according to sound field
and sensor sensitivity before application. Simulation and experimental results indicate that there exist linear
relationships between sampling rates and signal amplitude under three algorithms, that sampling points per
wavelength need to be 8, 4 and 2 times of signal amplitude, respectively. In addition, compared with differential
cross-multiplying (DCM) algorithm, arctangent algorithms all perform better on real time and accuracy when
satisfying sampling rate requirements.
Keywords: Fiber-optic acoustic sensing; Arctangent demodulation; 3 × 3 coupler

2022-07-18 收稿; 2022-09-02 定稿
国家自然科学基金项目 (11674351)
∗
作者简介: 安秉文 (1998– ), 女, 辽宁铁岭人, 硕士研究生, 研究方向: 检测声学。
通信作者 E-mail: wuxm@mail.ioa.ac.cn
†