Page 37 - 《应用声学》2020年第6期
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第 39 卷 第 6 期                                                                       Vol. 39, No. 6
             2020 年 11 月                         Journal of Applied Acoustics                 November, 2020

             ⋄ 研究报告 ⋄



                         浅海波导中简正波干涉特征频率增强                                                      ∗






                                           孟瑞洁     1,2   周士弘     1†   戚聿波     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：针对浅海波导中水平线列阵接收的低频宽带低信噪比信号，提出了一种利用多拍信号相干累加来提高
                干涉简正波特征频谱信噪比的方法。这种方法主要针对未知距离和声源形式的运动声源，对不同时刻 (或接收
                距离) 处阵列输出信号进行 warping 变换，根据干涉简正波的特征频率不变性，通过搜索距离与径向速度的比
                值来对齐未知距离下 warping 变换后的谱峰频率，进而通过相干累加来增强信号干涉简正波的特征频率。仿
                真和海上实验数据分析均验证了方法的性能。
                关键词：浅海波导；warping 变换；简正波干涉特征频率；相干累加；特征增强
                中图法分类号: O427.9          文献标识码: A          文章编号: 1000-310X(2020)06-0831-08
                DOI: 10.11684/j.issn.1000-310X.2020.06.005




                 Enhancement of characteristic frequency of coherent normal mode pairs in
                                              shallow water waveguides




                                       MENG Ruijie  1,2  ZHOU Shihong 1  QI Yubo 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: Aiming at the low-frequency and low signal-to-noise ratio signals received by a horizontal line array
                 in shallow-water waveguides, an approach to enhance the signal-to-noise ratio of characteristic spectra of the
                 coherent normal mode pairs is proposed based on coherent accumulation of multiple snapshot signals. For a
                 moving sound source without knowledge of range and waveform, warping transform is performed on the array
                 output signals at different time or receiving ranges. According to the characteristic frequency invariability of the
                 coherent normal modes, the peak frequency after warping transform at unknown range is aligned by searching
                 the ratio of range to radial velocity. And then, coherent accumulation is used to enhance the characteristic
                 frequency of the coherent normal mode pairs. The simulation and the analysis of marine experimental data
                 verify the performance of the approach.
                 Keywords: Shallow water waveguide; warping transform; Characteristic frequency of coherent normal mode
                 pairs; Coherent accumulation; Feature enhancement



             2020-03-25 收稿; 2020-04-26 定稿
             中国科学院前沿科学重点研究项目 (QYZDY-SSW-SLH005), 国家自然科学基金项目 (11804362, 11804364)
             ∗
             作者简介: 孟瑞洁 (1991– ), 女, 陕西渭南人, 博士研究生, 研究方向: 水声物理。
             †  通信作者 E-mail: shih_zhou@mail.ioa.ac.cn
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