MATLAB信號(hào)處理實(shí)習(xí)報(bào)告楊越

MATLAB信號(hào)處理實(shí)習(xí)218-MATLAB信號(hào)處理實(shí)習(xí)報(bào)告實(shí)習(xí)名稱MATLAB信號(hào)處理實(shí)習(xí)題目數(shù)字信號(hào)處理專業(yè)班級(jí)電子1142姓名楊越學(xué)號(hào)1104451237成績(jī)?cè)u(píng)定考核內(nèi)容設(shè)計(jì)表現(xiàn)設(shè)計(jì)報(bào)告設(shè)計(jì)成果和答辯綜合評(píng)定成績(jī)成績(jī)電氣與信息學(xué)院二零一四年六月

實(shí)習(xí)考核和成績(jī)?cè)u(píng)定辦法1、實(shí)習(xí)的考核由指導(dǎo)教師根據(jù)設(shè)計(jì)表現(xiàn)（出勤、遵守紀(jì)律情況等）、設(shè)計(jì)報(bào)告、設(shè)計(jì)成果、答辯等幾個(gè)方面，給出各項(xiàng)成績(jī)或權(quán)重，綜合后給出實(shí)習(xí)總成績(jī)。該設(shè)計(jì)考核須經(jīng)教研室主任審核，主管院長(zhǎng)審批備案。2、成績(jī)?cè)u(píng)定采用五級(jí)分制，即優(yōu)、良、中、及格和不及格。3、參加本次設(shè)計(jì)時(shí)間不足三分之二或曠課三天以上者，不得參加本次考核，按不及格處理。4、實(shí)習(xí)結(jié)束一周內(nèi)，指導(dǎo)教師提交成績(jī)和設(shè)計(jì)總結(jié)。5、設(shè)計(jì)過(guò)程考核和成績(jī)?cè)诮處熓謨?cè)中有記載。注意：1、實(shí)習(xí)任務(wù)書和指導(dǎo)書在實(shí)習(xí)前發(fā)給學(xué)生，設(shè)計(jì)任務(wù)書放置在設(shè)計(jì)報(bào)告封面后和正文目錄前。2、為了節(jié)省紙張，保護(hù)環(huán)境，便于保管設(shè)計(jì)報(bào)告，統(tǒng)一采用A4紙，實(shí)習(xí)報(bào)告建議雙面打印（正文采用宋體五號(hào)字）或手寫，左側(cè)裝訂。MATALB信號(hào)處理實(shí)習(xí)報(bào)告一、實(shí)習(xí)目的“數(shù)字信號(hào)處理”是電子信息工程專業(yè)的主干課程，其理論性較強(qiáng)，學(xué)生通過(guò)理論課的系統(tǒng)學(xué)習(xí)后，應(yīng)通過(guò)MATLAB語(yǔ)言對(duì)其所涉及的算法進(jìn)行仿真，這不僅能幫助學(xué)生理解其抽象的物理概念，工程概念和復(fù)雜算法，加強(qiáng)感性認(rèn)識(shí)，而且能激發(fā)學(xué)生更進(jìn)一步地在該領(lǐng)域的學(xué)習(xí)和探索熱情。二、實(shí)習(xí)任務(wù)及功能概述1.FT與DFT關(guān)系的MATLAB仿真任務(wù)要求：任設(shè)一個(gè)長(zhǎng)度為N的實(shí)序列；編寫MATLAB代碼，實(shí)現(xiàn)該序列的傅立葉變換和離散傅立葉變換；調(diào)試運(yùn)行代碼，得到仿真圖形；（4）通過(guò)仿真圖形觀察二者的關(guān)系，并得出結(jié)論。實(shí)驗(yàn)源程序function[X,Xk]=yydft(x,N)w=2*pi*(0:127)/128;X=x*exp(-j*[1:length(x)]'*w);subplot(211)plot(w,abs(X))title('電子1142楊越')k=0:N-1;XK=x*exp(-j*[1:length(x)]'*(2*pi*k)/N);subplot(212)stem(k,abs(XK))title('FT與DFT關(guān)系的MATLAB仿真')endDFT的快速算法FFT的仿真任務(wù)要求：在熟悉FFT算法原理的基礎(chǔ)上，對(duì)所給的時(shí)域信號(hào)進(jìn)行分析；對(duì)信號(hào)做時(shí)域分析時(shí)要注意混疊現(xiàn)象的發(fā)生；對(duì)混合信號(hào)做快速傅立葉變換FFT運(yùn)算，其中、、自設(shè)，變換點(diǎn)數(shù)根據(jù)所設(shè)的情況自定；對(duì)變換結(jié)果做分析。實(shí)驗(yàn)源程序function[x,xfft]=yyfft(f1,f2,f3,fs,n)t=0:1/fs:1;x=sin(2*pi*f1*t)+sin(2*pi*f2*t)+sin(2*pi*f3*t);subplot(211)plot(t,x)title('DFT的快速算法FFT的仿真')subplot(212)xfft=fft(x,n)f=fs*(0:n/2-1)/n;plot(f,abs(xfft(1:n/2)))title('電子1142楊越')endf1=20f2=40f3=60fs=120n=643.利用MATLAB信號(hào)處理工具箱設(shè)計(jì)FIR濾波器要求如下：(1)熟悉FIR濾波器的工作原理；(2)設(shè)計(jì)一個(gè)N階高通數(shù)字濾波器，階數(shù)和截止頻率自定；(3)設(shè)計(jì)一個(gè)N階帶通數(shù)字濾波器，階數(shù)和截止頻率自定；設(shè)計(jì)一個(gè)N階低通數(shù)字濾波器，階數(shù)和截止頻率自定；有完整的MATLAB代碼。實(shí)驗(yàn)源代碼帶通：function[h,s,sf]=yyFIRbandpassfilter(f1,f2,f3,fs)m=(0.3*f1)/(fs/2);M=round(8/m);N=M-1;b=fir1(N,[0.8*f2/(fs/2)1.2*f2/(fs/2)]);[h,f]=freqz(b,1,512);axes('position',[0.10.760.33.2])plot(f*fs/(2*pi),20*log10(abs(h)))xlabel('frequency/Hz','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')t=0:1/fs:1;s=sin(2*pi*f1*t)+sin(2*pi*f2*t)+sin(2*pi*f3*t);axes('position',[0.10.430.33.2])plot(t,s);xlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')sf=filter(b,1,s);axes('position',[0.10.10.33.2])plot(t,sf)axis([0.2.5xlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')endf1=10f2=20f3=30fs=60低通：function[h,s,sf]=yyFIRlowpassfilter(f1,f2,fs)m=(0.3*f1)/(fs/2);M=round(8/m);N=M-1;b=fir1(N,0.9*f2/(fs/2));[h,f]=freqz(b,1,512);plot(f*fs/(2*pi),20*log10(abs(h)))xlabel('frequency/Hz','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')figuresubplot(211)t=0:1/fs:1;s=sin(2*pi*f1*t)+sin(2*pi*f2*t);plot(t,s);xlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')subplot(212)SK=fft(s,512);SXK=abs(SK);f=(0:255)*fs/512;plot(f,SXK(1:256))xlabel('Frequency/Hz','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')figuresf=filter(b,1,s);%filterssubplot(211)plot(t,sf)%drawfilteredsignalsfxlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')axis([0.2.5-22])subplot(212)SFK=fft(sf,512);SFXK=abs(SFK);f=(0:255)*fs/512;plot(f,SFXK(1:256))xlabel('Frequency/Hz','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')end高通：function[h,s,sf]=yyFIRbandpassfilter(f1,f2,f3,fs)m=(0.3*f1)/(fs/2);M=round(8/m);N=M-1;b=fir1(N,[0.8*f2/(fs/2)1.2*f2/(fs/2)]),'high';[h,f]=freqz(b,1,512);axes('position',[0.10.760.33.2])plot(f*fs/(2*pi),20*log10(abs(h)))weight','bold')set(gca,'fontsize',8,'fontweight','bold')t=0:1/fs:1;s=sin(2*pi*f1*t)+sin(2*pi*f2*t)+sin(2*pi*f3*t);axes('position',[0.10.430.33.2])plot(t,s);xlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')sf=filter(b,1,s);axes('position',[0.10.10.33.2])plot(t,sf)axis([0.2.5-22])xlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')endxlabel('frequency/Hz','fontsize',8,'font4.利用MATLAB信號(hào)處理工具箱設(shè)計(jì)IIR濾波器要求如下：熟悉IIR數(shù)字濾波器的工作原理；設(shè)計(jì)一個(gè)N階高通數(shù)字濾波器，階數(shù)和截止頻率自定；設(shè)計(jì)一個(gè)N階帶通數(shù)字濾波器，階數(shù)和截止頻率自定；設(shè)計(jì)一個(gè)N階高通數(shù)字濾波器，階數(shù)和截止頻率自定；有完整的MATLAB代碼。實(shí)驗(yàn)源程序低通：function[x,m,xf,mf]=yylowIIRfilter(f1,f2,fs,n)subplot(411)t=0:1/fs:.5;x=sin(2*pi*f1*t)+sin(2*pi*f2*t);plot(t,x)subplot(412)y=fft(x,n);m=abs(y)/max(abs(y));f=fs*(0:n/2-1)/n;plot(f,m(1:n/2));[b,a]=ellip(6,.1,40,.5*(f1+f2)/(fs/2));xf=filter(b,a,x);subplot(413)plot(t,xf);subplot(414)yf=fft(xf,n);mf=abs(yf)/max(abs(yf));f=fs*(0:n/2-1)/n;plot(f,mf(1:n/2));endf1=100f2=200fs=400n=32高通：function[x,m,xf,mf]=yyhighIIRfilter(f1,f2,fs,n)subplot(411)t=0:1/fs:.5;x=sin(2*pi*f1*t)+sin(2*pi*f2*t);plot(t,x)subplot(412)y=fft(x,n);m=abs(y)/max(abs(y));f=fs*(0:n/2-1)/n;plot(f,m(1:n/2));[b,a]=ellip(6,.1,40,.5*(f1+f2)/(fs/2),'high');xf=filter(b,a,x);subplot(413)plot(t,xf);subplot(414)yf=fft(xf,n);mf=abs(yf)/max(abs(yf));f=fs*(0:n/2-1)/n;plot(f,mf(1:n/2));endf1=100,f2=200,fs=400,n=32帶通function[x,m,xf,mf]=yypassIIRfilter(f1,f2,fs,n)subplot(411)t=0:1/fs:.5;x=sin(2*pi*f1*t)+sin(2*pi*f2*t);plot(t,x)subplot(412)y=fft(x,n);m=abs(y)/max(abs(y));f=fs*(0:n/2-1)/n;plot(f,m(1:n/2));[b,a]=ellip(6,.1,40,[0.8*f2/(fs/2)1.2*f2/(fs/2)],'high');xf=filter(b,a,x);subplot(413)plot(t,xf);subplot(414)yf=fft(xf,n);mf=abs(yf)/max(abs(yf));f=fs*(0:n/2-1)/n;plot(f,mf(1:n/2));end5.利用所設(shè)計(jì)的濾波器對(duì)混合信號(hào)進(jìn)行濾波要求如下:（1）設(shè)計(jì)一個(gè)IIR或FIR數(shù)字濾波器，將混合信號(hào)中的、或選擇出來(lái)，、、自定，濾波器類型自定；（2）有完整的MATALB代碼；（3）仿真結(jié)果；（4）結(jié)果分析。實(shí)驗(yàn)源程序使用function定義一個(gè)帶通FIR濾波器ftxuanpinfilters=sin(2*pi*f1*t)+sin(2*pi*f2*t)+sin(2*pi*f3*t);通過(guò)帶通分別選出三個(gè)頻率f1,f2,f3.function[h,s,sf]=ftxuanpinfilter(f1,f2,f3,fs)m=(0.3*f1)/(fs/2);%definetransitionbandwidthM=round(8/m);%definelengthofhammingwindowN=M-1;%defineorderofFIRfilterb=fir1(N,[0.8*f1/(fs/2)1.2*f1/(fs/2)]);%上下限截止頻率分別取f1的0.8和1.2[h,f]=freqz(b,1,512);axes('position',[0.10.730.8.2])plot(f*fs/(2*pi),20*log10(abs(h)))title('濾波器頻譜圖')xlabel('frequency/Hz','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')t=0:1/fs:1;s=sin(2*pi*f1*t)+sin(2*pi*f2*t)+sin(2*pi*f3*t);axes('position',[0.10.40.8.2])plot(t,s);title('原始信號(hào)f(t)的波形圖')xlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')sf=filter(b,1,s);axes('position',[0.10.080.8.2])plot(t,sf)title('選出f(t)中的f1的波形圖')axis([0.2.5-22])xlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')figureb1=fir1(N,[0.8*f2/(fs/2)1.2*f2/(fs/2)]);%上下限截止頻率分別取f2的0.8和1.2[h1,f1]=freqz(b1,1,512);axes('position',[0.10.730.8.2])plot(f1*fs/(2*pi),20*log10(abs(h)))title('濾波器頻譜圖')xlabel('frequency/Hz','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')axes('position',[0.10.40.8.2])plot(t,s);title('原始信號(hào)f(t)的波形圖')xlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')sf=filter(b1,1,s);axes('position',[0.10.080.8.2])plot(t,sf)title('選出f(t)中的f2的波形圖')axis([0.2.5-22])xlabel('time/Second','fontsize',8,'fontweight','bold')set(gca,'fontsize',8,'fontweight','bold')figureb2=fir1(N,[0.8*f3/(fs/2)1.2*f3/(fs/2)]);%上下限截止頻率分別取f3的0.8和1.2[h2,f2]=freqz(b2,1,512);axes('position',[0.10.730.8.2])plot(f2*fs