Page 74 - 《应用声学》2022年第1期

第 41 卷 第 1 期 Vol. 41, No. 1
2022 年 1 月 Journal of Applied Acoustics January, 2022

⋄ 研究报告 ⋄

采用子带二值加权累积的经验格林函数提取 ∗

郭启超 1,2 李风华 1† 杨习山 1

(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)

摘要：提出一种采用子带二值加权累积的海洋环境噪声互相关函数 (NCF) 提取经验格林函数 (EGF) 方法。
首先将每一快拍 NCF 在频域划分为多个子带，每个子带内根据 “累积后提取的 EGF 信噪比增加” 的准则，确
定各快拍 NCF 的加权系数为 0 或 1，将各子带的加权累积结果谱白化后在频域拼接，再反傅里叶变换得到时
域 EGF。子带二值加权累积方法实现了每一快拍 NCF 累积前的频率自动选择，相比于已有的原始累积方法
与时域二值加权累积算法，可以有效提高从较宽频率带宽的海洋环境噪声中提取 EGF 的信噪比。海试实验数
据验证了该方法的有效性与优越性。
关键词：经验格林函数；噪声互相关函数；子带二值加权
中图法分类号: P714.1 文献标识码: A 文章编号: 1000-310X(2022)01-0070-07
DOI: 10.11684/j.issn.1000-310X.2022.01.008

Empirical Green’s function extraction based on binary sub-band
weighted stacking

GUO Qichao 1,2 LI Fenghua 1 YANG Xishan 1

(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)

Abstract: A method to extract empirical Green’s function (EGF) from oceanic ambient noise cross-correlation
function (NCF) based on sub-band binary weighted stacking is proposed. Firstly, each snapshot of NCF is
divided into multiple sub-bands in the frequency domain. In each sub-band, the weighting coefficient of each
snapshot NCF is determined to be 0 or 1 according to an increase in the signal-to-noise ratio of extracted EGF
after stacking. The stacked sub-band results are spectral whitened and spliced in the frequency domain, and
then the inverse Fourier transform is used to obtain the time domain EGF. The sub-band binary weighted
stacking method realizes the adaptive selection of the frequency of each snapshot of NCF before stacking.
Compared with the original stacking method and the time-domain binary stacking algorithm, the proposed
method can effectively improve the signal-to-noise ratio of EGF extracted from oceanic ambient noise with a
relatively wide frequency bandwidth. The sea trial data verifies the effectiveness and superiority of the proposed
method.
Keywords: Empirical Green’s function; Noise cross-correlation function; Sub-band binary weighted stacking

2021-03-15 收稿; 2021-04-09 定稿
国家自然科学基金项目 (11974017, 11874061)
∗
作者简介: 郭启超 (1993– ), 男, 山东聊城人, 博士研究生, 研究方向: 水声物理。
通信作者 E-mail: lfh@mail.ioa.ac.cn
†