ex1_2.m

matlab exprience,M文件,实验代码

N=100;
ki=20;
n=0:1:N-1;
heaviside=ones(1,N);
heaviside_right_20=[zeros(1,ki),ones(1,N-ki)];
g_n=heaviside-heaviside_right_20;
yn=0.8.^n;
xn=yn.*g_n;

k=[0:1:N-1];
WN=exp(-j*2*pi/N);
nk=n'*k;WNnk=WN.^nk;
Xk=xn*WNnk;
figure(1)
stem(n,xn)
title('original time data(x(n))')
figure(2)
stem(k,abs(Xk))
title('DTFT[xn]')