目前,LabVIEW
广泛应用于自动化、通信、电路设 计和生产、过程控制等各种工业领域中,用来提高应用系统的开发效率,但很少应用于宽频的声音信号系统中。
本设计以LabVIEW为主要软件开发环境,搭建声音振动信号采集测试平台。该平台经过了多组给定频率信号的测 试,证明系统的正确性。利用麦克和计算机声卡作为声音信号采集的硬件,在LabVIEW环境下开发了计算机音频采集分析系统.本系统能够采集各种工况环境的声音信号,并具有信号保存、调用、回放等功能,同时实现了对声音信号的各种数字分析,为声音振动研究和工况状态识别提供了有效的工具。最后完成对声音信号采集的硬件设计,包括传感器的选型、采集通道的设计、仿真程序的编写、用户采集界面的生成。通过搭建的测试平台设计出良好的人机界面。
关键词:虚拟仪器;LabVIEW
;声音信号;时频分析;数字滤波器
At present, LabVIEW is widely used in automation, communication, circuit design and production, process control and other industrial fields, used to improve the application system development efficiency, but rarely used in broadband voice signal system.
The design of LabVIEW as the main software development environment, set up a sound vibration signal acquisition test platform. The platform has been tested with multiple sets of frequency signals to prove the correctness of the system. Using the microphone and computer sound card as the sound signal acquisition hardware, in the LabVIEW environment developed a computer audio acquisition and analysis system. The system can collect the sound signal of various working conditions, and has the functions of signal preservation, call, playback and so on. At the same time, it can realize various digital analysis of sound signal, which provides effective tool for sound vibration research and condition state identification The Finally, the hardware design of the sound signal acquisition is completed, including the selection of the sensor, the design of the acquisition channel, the preparation of the simulation program and the generation of the user acquisition interface. Through the construction of the test platform to design a good man-machine interface.
Key words: virtual instrument; LabVIEW; sound signal; time-frequency analysis; digital filter
摘 要 I
Abstract I
目 录 III
第1章 绪 论 1
1.1 引言 1
1.2 声音信号处理的发展及应用 2
1.3 本课题研究任务及章节安排 3
第2章 系统设计方案 4
2.1系统基本概述 4
2.2系统总体实现 5
2.3系统框图 6
第3章 声音信号的采集 7
3.1 声音信号的采集方法 7
3.2 声卡的相关介绍及参数设置 9
3.2.1 LabVIEW中的相关声卡函数 9
3.2.2声卡的参数及设置 11
3.3 读取历史声音信号的设计 13
第4章 基于LabVIEW的声音信号分析的实现 14
4.1声音信号的时域分析 14
4.1.1声音信号的预处理 14
4.1.2声音信号的短时能量和短时平均幅度函数 16
4.1.3声音信号的短时自相关函数和短时平均幅度差函数 17
4.2声音信号的频域分析 17
4.3滤波器的设计及滤波实现 19
4.4声音信号的综合实现 22
4.4.1声音分析系统的整体设计 22
4.4.2声音信号的时频分析 23
第5章 总结 24
参考文献 25
致 谢 26
附 录 27