基于Matlab滤波器设计演示

b
FIR FILTERS EQUIRIPPLE OPTIMUM:
Fpass1 1000Hz Fstop 1200Hz
Apass 1dB
Astop 80dB
6
SPEECH SIGNAL PROCESSING
In this part, we mainly use the Window method, Equiripple Optimum, in addition we simulate a Highpass filter to make a comparison.
In this part, we mainly use Butterworth，Chebyshev and Elliptic Method, which contains three kinds of filters below.
IIR FILTERS
b
CHEBYSHEV:
Fpass1 1000Hz Fstop 1200Hz
Mixed Instrument
GUITAR
2012 GRADUATES
VIOLIN
2013 GRADUATES
In this part, we mix the sound of guitar（low frequency） and violin （high frequency）and filter them from each other with a lowpass filter and highpass filter. Thus we can obtain clear sound after processing。
It’s hard to choose a better one filter but when we really need some properties of a certain filter. And a speech signal is consist of
a variety of frequencies, which cause it not that easy to get a ideal speech signal, thus we have use more kinds of filters like bandpass or use them at a same time
c
FIR FILTERS HIGHPASS:
Fpass 750Hz Apass 1dB
Fstop 700Hz
Astop 80dB
7
SPEECH SIGNAL PROCESSING
In this part, we mainly use Butterworth，Chebyshev and Elliptic Method, which contains three kinds of filters below.
Mixed Instrument
GUITAR
2012 GRADUATES
VIOLIN
2013 GRADUATES
In this part, we mix the sound of guitar（low frequency） and violin （high frequency）and filter them from each other with a lowpass filter and highpass filter. Thus we can obtain clear sound after processing。
1 0.9 0.8 0.7 0.6 0.3 0.5 0.4 0.2 0.3 0.2 0.1 0 0 0 500 1000 1500 2000 Frequency(Hz) 2500 3000 0.1 0.4 0.5
0
500
1000
1500 2000 Frequency(Hz)
2500
3000
Frequency analysis of Guitar
IIR FILTERS
a
BUTTERWORTH:
Fpass 700Hz Apass 1dB Fstop 750Hz
Astop 80dB
Speech signal processing&digit al signal processing
IIR
8
SPEECH SIGNAL PROCESSING
1
Membes
BU DONG WU Speech Signal Processing On Matlab
14th ,Dec, 2012
2
SPEECH SIGNAL PROCESSING
Abstract
A s w e a ll kn o w ，filte r is a vita l im p le m e n ta tio n o f d ig ita l sig n a l p ro c e s s in g . T o d a y w e w ill u s e M a tla b to p ro c e s s a vo ic e file w ith se v e ra l filte rs d e s ig n e d , b y w h ic h to m a k e a co m p a ris o n , a n d d ra w so m e p ro p e rtie s o f th e m .
Apass 1dB
Astop 80dB
Speech signal processing&digit al signal processing
IIR
9
SPEECH SIGNAL PROCESSING
In this part, we mainly use Butterworth，Chebyshev and Elliptic Method, which contains three kinds of filters below.
* DIGITAL SIGNAL PROCESSING
Above is all about our presentation
SPEECH SIGNAL PROCESSING
THANKS!
滤波信号波形
原始信号波形 2.5 2 1.5 1 0.5 0 0 2000 4000 6000 0.2 0 0.6 0.4
0
2000
4000
6000
Before Highpass Processing
After Highpass Processing
12
SPEECH SIGNAL PROCESSING
IIR
Instrument NOISE
FIR
3
4
SPEECH SIGNAL PROCESSING
In this part, we mainly use the Window method, Equiripple Optimum, in addition we simulate a Highpass filter to make a comparison.
A SIMPLE GUI INTERFACE
3
SPEECH SIGNAL PROCESSING
[
contents
]
Speech signal by FIR filter Speech signal by IIR filter Remix instrument process Comparisons
Frequency analysis of Violin
11
SPEECH SIGNAL PROCESSING
Mixed Instrument
GUITAR
2012 GRADUATES
VIOLIN
2013 GRADUATES
In this part, we mix the sound of guitar（low frequency） and violin （high frequency）and filter them from each other with a lowpass filter and highpass filter. Thus we can obtain clear sound after processing。
IIR FILTERS
c
ELLIPTIC:
Fpass 1000Hz Fstop 1200Hz
Apass 1dB
Astop 80dB
Speech signal processing&digit al signal processing
IIR
百度文库
10
SPEECH SIGNAL PROCESSING
a
FIR FILTERS WINDOW:
Fpass 1000Hz Fstop 1200Hz
Apass 1dB
Astop 50dB
5
SPEECH SIGNAL PROCESSING
In this part, we mainly use the Window method, Equiripple Optimum, in addition we simulate a Highpass filter to make a comparison.
滤波信号波形
原始信号波形 1 1
0.5
0.5
0
0
1000
2000
3000
0
0
1000
2000
3000
Before Lowpass Processing
After Lowpass Processing
13
SPEECH SIGNAL PROCESSING
COMPARISON
FIR filter：high orders obvious sidelobes good linear property IIR filter：low orders attenuated sidelobes bad linear property