matlab序列的运算.docx

实验三 序列的运算一、实验内容1、序列的乘积：仿真并完成例题1.222、序列的移位：编写seqshift()函数，实现序列的移位，并作图验证。3、序列的卷积：编写convwthn()函数，实现具体序列的卷积，并且进行理论计算，比较结果。4、序列的相关：仿真并完成例题1.24二、MATLAB仿真1、序列的乘积 解： function y,n = seqadd(x1,n1,x2,n2) n=min(n1),min(n2):max(n1):max(n2); y1=zeros(1,length(n);y2=y1; y1(find(n=min(n1)&(n=min(n2)&(n=min(n1)&(n=min(n2)&(n=ns1)&(n=ns2)&(n=nf2)=1)=x2;ya=y1+y2;ym=y1.*y2;subplot(221);stem(n1,x1,*,r);ylabel(x1(n);grid;subplot(223);stem(n2,x2,*,r);xlabel(n);ylabel(x2(n);grid;subplot(222);stem(n,ya,*,r);ylabel(y1(n)+y2(n);grid;subplot(224);stem(n,ym,*,r);xlabel(n);ylabel(y1(n)*y2(n);grid;如图1所示。clc;clear all;x1=1,3,5,7,6,4,2,1;ns1=-3;x2=4,0,2,1,-1,3;ns2=1;nf1=ns1+length(x1)-1;nf2=ns2+length(x2)-1;n1=ns1:nf1;n2=ns2:nf2;ya,n = seqadd(x1,n1,x2,n2);ym,n = seqmult(x1,n1,x2,n2);subplot(221);stem(n1,x1,*,r);ylabel(x1(n);grid;subplot(223);stem(n2,x2,*,r);xlabel(n);ylabel(x2(n);grid;subplot(222);stem(n,ya,*,r);ylabel(y1(n)+y2(n);grid;subplot(224);stem(n,ym,*,r);xlabel(n);ylabel(y1(n)*y2(n);grid;图12、序列的移位解： function y,ny = seqshift(x,nx,m)ny = nx+m;y = x;代码：clc;clear allx=1,2,3,4,5;nx=-2:2;m=2; %向右移2个单位y,ny = seqshift(x,nx,m);subplot(211);stem(nx,x,*,r);title(原序列x(n);xlabel(n);ylabel(x(n);subplot(212);stem(ny,y,*,r);title(移位后序列y(n);xlabel(n);ylabel(y(n);grid;如下图2所示：图23、序列的卷积解： function y,ny = convwthn(x,nx,h,nh)ny1 = nx(1)+nh(1);ny2 = nx(end)+nh(end);y = conv(x,h);ny = (ny1:ny2);代码：clc;clear all;x = 1,2,3,-1,-2;nx = -1:3;h = 2,2,1,-1,4,-2;nh = -3:2;y,ny = convwthn(x,nx,h,nh);stem(ny,y,*,r);xlabel(n);ylabel(y(n);grid;x(n)与h(n)相卷积得到的图形如图3所示：图34、序列的相关解： function y,ny = convwthn(x,nx,h,nh)ny1 = nx(1)+nh(1);ny2 = nx(end)+nh(end);y = conv(x,h);ny = (ny1:ny2);代码：clc;clear allx = 2,1,3,2,1,5,1;nx = 1:7;y = 2,1,3,4;ny = 1:4;N1 = length(x)-1;N2 = length(y)-1;rxy = convwthn(fliplr(y),-ny,x,nx);k = -(N2):N1;stem(k,rxy,*,r);xlabel(n);ylabel(rxy(n);title( x(n)与y(n)之间的互相关);axis(-N2,N1,0,35);grid;图4 三、实验小结通过这次实验使我知道序列的卷积可以通过matlab实现。Matlab里本身有丰富的库函