matlab滤波器与均衡器设计方案 .docx

精品名师归纳总结封面可编辑资料 - - - 欢迎下载精品名师归纳总结作者： PanHongliang仅供个人学习可编辑资料 - - - 欢迎下载精品名师归纳总结Digital signal andanalysisTitle:A filter and equilizerName:YangxiaoClass:Master of mechanical engineering 1302StudentID:M202170503可编辑资料 - - - 欢迎下载精品名师归纳总结Abstrac:tDesigning somekinds offiltersbyusingmatlab.We can understand thesignal processing offiltermorecomprehensive by analyzingthefilteringpropertiesofdifferentfilters.Designing anadjustable parameter of digital filter which is called equalizer.In this paper, the digital equalizer which is based on MATLAB platform designing has the functions ofaccessing Wav file , filtering and playing.可编辑资料 - - - 欢迎下载精品名师归纳总结Keyword:Matlab,Filter,Equalizer1.PrefaceMATLAB is called Matrix Laborator，ywhich is designed by the可编辑资料 - - - 欢迎下载精品名师归纳总结United States MathWorks company.Its a commercial mathematical software. Matlab can be use for Matrix operations, mapping functionsand data, algorithm, creating the user interface, connect to other programming languages procedures, mainly used in engineering calculations, control design, signal processing and communications, image processing, signal detection, design and financial modeling analysis and other fields. GUI Graphical User Interface, referred to as GUI, known Graphical User Interface is displayed using the graphical user interface of computer operations. Matlab has a powerful GUl tool. In this report, by using matlab GUI tool we could design a signal filter and equalizer.The filter Can be divided into low-pass, high-pass filter, band pass andband-stop filter.Low-pass filter: it allows signal in low frequency or dc可编辑资料 - - - 欢迎下载精品名师归纳总结component through, suppress the high frequency component or the interference and noise.High-pass filter: it allows the signal in high frequency , restrain low frequency or dc component.Band-pass filter: it allows a spectrum of signal through and restrain the signal below or above the spectrum, interference and noise.Band-stop filter: it inhibit the signal within a certain frequency band and pass the signal outside the spectrum.2. IntroduceThe filter which is designed by using matlab have four functions :low- pass,high-pass,band-stop and band-pass .Every function could input the cut-off frequencies.The equalizer could filter the wav file inputted as we want.The interface is that:可编辑资料 - - - 欢迎下载精品名师归纳总结3. Design Principles2.1 Interface可编辑资料 - - - 欢迎下载精品名师归纳总结The task is to design the filter and equalizer which can edit the inputting signal as we want and choose the frequency spectrum to pass.3.1 the standard signal inputWe design a signal generator which is used to generator standard waveform such as sin,square,triangular,sawtooth and noise.And we can decide whether adding different waves .The program is:Fs=10000。可编辑资料 - - - 欢迎下载精品名师归纳总结N=400。x=linspace0,N/Fs,N。t=gethandles.WaveMake,'Value'。f=str2doublegethandles.frequency,'String'。a=str2doublegethandles.amplitude,'String'。 p=0。switch tcase 1y=a*sin2*pi*x*f+p。if gethandles.add,'Value'=0.0 handles.y=y。elsehandles.y=handles.y+y。 endcase 2.case 5y=a*2*randsizex-1 。if gethandles.add,'Value'=0.0 handles.y=y。elsehandles.y=handles.y+y。可编辑资料 - - - 欢迎下载精品名师归纳总结endend handles.inputtype=3。guidatahObject,handles。plothandles.axes1,handles.y。 xlim0 200 。temple=handles.y。f=linspace0,Fs/2,N/2。P=2*ffttemple,N/N 。Pyy=sqrtP.* conjP。plothandles.axes2,f,Pyy1:N/2。The interface is:3.1 the image of waveform3.2 the wave filteringBy choosing the working mode of filter and input cut-off frequencies we can realize the filtering.Theprogram is:y=handles.y。FC=str2doublegethandles.hf,'string'。Fs=22000。n=44100。N=8。Wn=FC/Fs/2。可编辑资料 - - - 欢迎下载精品名师归纳总结% the low-pass program b,a = butterN,Wn,'low' 。z=filterb,a,y 。P=fftz,n 。f=linspace0,Fs/2,n/2。Pyy=2*sqrtP.* conjP/n。plothandles.axes3,z。plothandles.axes4,f,Pyy1:n/2。handles.z=z。guidatahObject,handles。By running the program we can realize low-pass filter3.2 the image of low-pass filter The high-pass program is:b,a = butterN,Wn,'high' 。z=filterb,a,y 。P=fftz,n。f=linspace0,Fs/2,n/2。Pyy =2*sqrtP.* conjP/n。plothandles.axes3,z。plothandles.axes4,f,Pyy1:n/2。handles.z=z。guidatahObject,handles。可编辑资料 - - - 欢迎下载精品名师归纳总结By running the program we can realize high-pass filter3.3 the image of high-pass filter The band-stop program is:b,a = butterN,Wn,'stop'。z=filterb,a,y 。P=fftz,n。f=linspace0,Fs/2,n/2。Pyy=2*sqrtP.* conjP/n。plothandles.axes3,z。plothandles.axes4,f,Pyy1:n/2。handles.z=z。guidatahObject,handles。By running the program we can realize band-stop filter3.4 the image of band-stop filter The band-pass program is:b,a = butterN,Wn,'bandpass'。z=filterb,a,y 。P=fftz,n。f=linspace0,Fs/2,n/2。handles.Pyy=2*sqrtP.* conjP/n 。plothandles.axes3,z。可编辑资料 - - - 欢迎下载精品名师归纳总结plothandles.axes4,f,handles.Pyy1:n/2。handles.z=z。guidatahObject,handles。By running the program we can realize band-pass filter3.5 the image of band-pass filter3.3 the equalizer filteringWe can open a wav file by run this program: filename,pathname=uigetfile'*.wav','select a wavfile' 。if isequalfilename,0disp'the user cancels to select。'elsestr=strcatpathname,filename。dispstrcat'the user select ',str。sethandles.filename,'string',str。end y,Fs,bits=wavreadstr。handles.y=y。handles.z=y。guidatahObject,handles。When we choose a wav file, we can realize equalizer filter by setting the values of The scroll bars and run the program:可编辑资料 - - - 欢迎下载精品名师归纳总结handles.a=handles.y:,1。y=handles.a。l=lengthy 。Fs=44100。%t=0:l-1/Fs 。Y=zerossizey。A1=gethandles.slider1,'value'。b,a=butter2,30/Fs/2,60/Fs/2,'bandpass'。Y=Y+2*A1*filterb,a,y。A2=gethandles.slider2,'value'。b,a=butter2,60/Fs/2,100/Fs/2,'bandpass'。Y=Y+2*A2*filterb,a,y。A3=gethandles.slider3,'value'。b,a=butter2,100/Fs/2,200/Fs/2,'bandpass'。Y=Y+2*A3*filterb,a,y。A4=gethandles.slider4,'value'。b,a=butter2,200/Fs/2,500/Fs/2,'bandpass'。Y=Y+2*A4*filterb,a,y。A5=gethandles.slider5,'value'。b,a=butter2,500/Fs/2,1000/Fs/2,'bandpass'。Y=Y+2*A5*filterb,a,y。A6=gethandles.slider6,'value'。可编辑资料 - - - 欢迎下载精品名师归纳总结b,a=butter2,1000/Fs/2,2000/Fs/2,'bandpass'。Y=Y+2*A6*filterb,a,y。A7=gethandles.slider7,'value'。b,a=butter2,2000/Fs/2,4000/Fs/2,'bandpass'。Y=Y+2*A7*filterb,a,y。A8=gethandles.slider8,'value'。b,a=butter2,4000/Fs/2,8000/Fs/2,'bandpass'。Y=Y+2*A8*filterb,a,y。z=Y 。Fs=44100。ysize=sizehandles.y。N=str2doublenum2strysize1。wavplayz,Fs。P=ffty,N 。Pyy1=2*sqrtP.*conjP/N 。P=fftz,N 。Pyy =2*sqrtP.* conjP/N 。f=linspace0,Fs/2,N/2。%Original wave time=1:lengthy/Fs 。plothandles.axes1,time,y。%Original frequency可编辑资料 - - - 欢迎下载精品名师归纳总结plothandles.axes2,f,Pyy11:N/2。%The equilizer wave plothandles.axes3,time,z。%The equilizer frequencyplothandles.axes4,f,Pyy1:N/2。guidatahObject,handles。The interface is:3.6 the image of equalizerWe can see the equalizer realize the function of frequency filtering well.4 .Exist problemThe interfaces are not enough beautifulThe equlizer cann't realize Pause, fast forward, and so on. The spectrum of music cannot be updated in real time.5. ConclusionWith the complement of the third project, the whole projects in the course have been finished.From the beginning when I dont know the content as well as the soft matlab very much ,in the end when I have complete all the projects with the matlab,it is really not easy.There is no need to say that I can make a simple system with the soft matlab now. The last one ,the filter and equalizer is the combination of可编辑资料 - - - 欢迎下载精品名师归纳总结the knowledge that is obtained from the designing the first two projects.With the basis of knowledge in the course as well as matlab, I will not be afraid of the problem. Nothing is impossible to a willing mind. If we make up our minds to do a thing ,we will solve all the problems in the可编辑资料 - - - 欢迎下载精品名师归纳总结last.References可编辑资料 - - - 欢迎下载精品名师归纳总结1 薛山. MATLAB 基础教程 .M 北京：清华高校出版社， 2021.3版权申明本文部分内容，包括文字、图片、以及设计等在网上搜集整理。版权为潘宏亮个人全部This article includes some parts, including text, pictures, and design. Copyright is Pan Hongliang's personal ownership.用户可将本文的内容或服务用于个人学习、争论或观看，以及其他非商业性或非盈利性用途，但同时应遵守著作权法及其他相关法律的规定，不得侵害本网站及相关权益人的合法权益。除此以 外，将本文任何内容或服务用于其他用途时，须征得本人及相关权益人的书面许可，并支付酬劳。Users may use the contents or services of this article for personal study, research or appreciation, and other non-commercial or non-profit purposes, but at the same time, they shall abide by the provisions of copyright可编辑资料 - - - 欢迎下载精品名师归纳总结law and other relevant laws, and shall not infringe upon the legitimate rights of this website and its relevant obligees. In addition, when any content or service of this article is used for other purposes, written permission and remuneration shall be obtained from the person concerned and the relevant obligee.转载或引用本文内容必需是以新闻性或资料性公共免费信息为使用目的的合理、善意引用，不得对本文内容原意进行曲解、修 改，并自负版权等法律责任。Reproduction or quotation of the content of this article must be reasonable and good-faith citation for the use of news or informative public free information. It shall not misinterpret or modify the original intention of the content of this article, and shall bear legal liability such as copyright.可编辑资料 - - - 欢迎下载