MATLAB的带噪声语音信号处理+滤波器设计
关键词： 数字信号处理；IIR滤波器；FIR滤波器；GUI界面
Speech signal processing with noise based on MATLAB
Abstract ：Digital signal processing is the use of digital signal processor and computer to process signal.It can be achieved by two ways of the software and hardware implementation.Compared with the hardware,Compared with the hardware, software implementation of an economic, a multi-purpose machine, etc., we use the software implementation.This paper carries on processing to the noisy speech signals using MATLAB software.First, we use the theoretical knowledge of digital signal processing in time domain and frequency domain analysis of the signal plus noise.Then two types of filter design, which uses Butterworth, Chebyshev and bilinear reform the infinite impulse response (Infinite Impulse Response design, IIR) filter,To design finite impulse response using window function method (Finite Impulse Response, FIR) filter.The simulation results show, not only using MATLAB signal processing toolbox can be used for signal analysis in time ，but also frequency domain characteristics, and can design to meet the requirements of the FIR and IIR digital filters quickly and efficiently .In this paper, a MATLAB GUI interface of the final design , each function module is integrated in the operating interface. By pressing the button and observe the display window, can be very intuitive to see each program running and operation results.
Keywords： digital filter；Infinite Impulse Response； Finite Impulse Response；GUI interface
目录
1. 绪论 1
1.1. 课题的目的和意义 1
1.2. 国内研究现状 1
1.3. 本课题的主要工作和内容 2
2. 原始语音信号采集与处理 4
2.1. 语音信号的采样理论依据 4
2.2. 语音信号的采集 5
2.3. 程序流程图 5
2.4. 原始语音信号的时域与频域分析 6
2.5. 语音信号加噪与频谱分析 6
3. 数字滤波器的设计 8
3.1. IIR数字滤波器 8
3.1.1. 可供选用的模拟滤波器 8
3.1.2. 双线性变换法 9
3.1.3. 所设计的IIR滤波器的频谱图 13
3.2. FIR数字滤波器 14
3.2.1. 用窗函数法设计FIR滤波器 15
3.2.2. 所设计的IIR滤波器的频谱图 16
3.3. 设计IIR滤波器与FIR滤波器的相同处与不同处 17
4. 进行滤波，比较滤波前后语音信号的波形及频谱 19
4.1. 用IIR滤波器和FIR滤波器滤波 19
4.2. 各个滤波器滤波得到的语音信号频谱图： 19