Page 72 - 《应用声学》2020年第4期

第 39 卷 第 4 期 Vol. 39, No. 4
2020 年 7 月 Journal of Applied Acoustics July, 2020

⋄ 研究报告 ⋄

超声换能器对线性调频信号脉冲压缩性能的

影响分析 ∗

王 强 1,2 毛 捷 1,2† 廉国选 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：该文研究了不同编码带宽下超声换能器对编码信号脉冲压缩后信噪比与轴向分辨率的影响关系。将脉
冲压缩后的时域峰值转化为频域积分的形式，得到考虑换能器影响的脉冲压缩信噪比公式。以线性调频信号
为例，仿真与实验结果表明，编码激励相对于方波激励的信噪比增益随编码带宽的减小而增大，因为受换能器
带宽限制，编码激励的轴向分辨率随编码带宽的增大先减小后趋于稳定。该研究为编码激励方法更有效地应
用于超声检测的背景中提供了参考。
关键词：脉冲压缩；信噪比；轴向分辨率
中图法分类号: TB553 文献标识码: A 文章编号: 1000-310X(2020)04-0558-05
DOI: 10.11684/j.issn.1000-310X.2020.04.009

Analysis of the influence of ultrasonic transducer on pulse compression
performance of chirp signal

WANG Qiang 1,2 MAO Jie 1,2 LIAN Guoxuan 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: In this paper, the effects of ultrasonic transducer on the signal-to-noise ratio and axial resolution
of coded signals after compression are studied under different coding bandwidths. The pulse-compressed time
domain peak is converted into the form of frequency domain integral, and the pulse compression signal-to-noise
ratio formula considering the influence of the transducer is obtained. Taking the chirp signal as an example,
the simulation and experimental results show that the signal-to-noise ratio gain of the coded excitation relative
to the square wave excitation increases with the decrease of the coding bandwidth. Because of the limitation of
transducer bandwidth, the axial resolution of coded excitation method decreases first and then stabilizes with
the increase of coding bandwidth. The research in this paper provides a reference for the application of coded
excitation method in the background of ultrasonic detection.
Keywords: Pulse compression; Signal-to-noise ratio; Axial resolution

2019-08-27 收稿; 2019-11-28 定稿
中科院创新基金项目 (CXJJ-16Z220)
∗
作者简介: 王强 (1991– ), 男, 山东潍坊人, 博士研究生, 研究方向: 信号与信息处理。
† 通信作者 E-mail: maojie@mail.ioa.ac.cn