数字信号处理(DSP)实验报告(精)

实验四M10.1Plotthemagnituderesponseofalinear-phaseFIRhighpassfilterbytruncatingtheimpulseresponsehHP[n]oftheidealhighpassfilterofEq.(10.17tolengthN=2M+1fortwodifferentvaluesofM,andshowthatthetruncatedfilterexhibitsoscillatorybehavioronbothsidesofthecutofffrequency.Code:M=800;n=-M:M;hn=-sin(0.4*pi*n./(pi*n;%hn=-0.4*sinc(0.4*n;hn(M+1=0.6;[H,w]=freqz(hn,1;plot(n,hnfigure,plot(w/pi,abs(HM10-1M10-2M11-1UsingProgram11-1,determinethefirst30samplesoftheimpulseresponsecoeFfiicientsofthefollowingfilters:(aFilter-oderellipticlowpassfilterdevelopedinExample9.14,(bFourth-oderType1ChebyshevhighpassfilterdevelopedinExample9.15,(cEight-oderButterworthbandpassfilterdevelpedinExample9.16.Code:N=8;xa=input('8点xa=';xb=input('8点xb=';xak=fft(xa,N;xbk=fft(xb,N;f=ifft(xak.*xbk,N;figure(1;subplot(5,1,1;stem(0:N-1,xa;title('xa(n';subplot(5,1,2;stem(0:N-1,xb;title('xb(n';subplot(5,1,3;stem(0:N-1,f;title('xa(n⊙xb(n';xak1=fft(xa,2*N;xbk1=fft(xb,2*N;h=ifft(xak1.*xbk1,2*N;subplot(5,1,4;stem(0:2*N-2,h(1:2*N-1;title('xa*xb';h=conv(xa,xb;subplot(5,1,5;stem(0:2*N-2,h(1:2*N-1;M11-1实验体会通过本次实验，通过此次DSP上机实验，进一步掌握和巩固了数字信号的相关知识，以及Matlab的相关操作，体验了将实际问题用软件进行实际应用的方法，为今后的学习和毕设夯实基础。使我对具有线性相位的有限长数字低通滤波器的设计原理、设计方法和设计步骤有了更进一步掌握。通过题目中给定的滤波器的指标，分别选择不同的窗函数形式，利用窗函数法设计FIR数字滤波器。由结果我们可以看出其他窗函数在边沿处比矩形窗变化要平滑而缓慢，逼近误差更小。对无限长单位冲激响应数字滤波器与有限长数字滤波器之间的不同点有了更进一步的理解和加深。