tex2.m

数字信号处理实验的程序

%Example2
M=80;
N=100;
n=1:M;
xn=cos(0.48*pi*n)+cos(0.52*pi*n);
n1=[0:1:N-1];y1=[xn(1:1:M),zeros(1,N-M)];
figure(1)
   subplot(2,1,1);stem(n1,y1);xlabel('n');
   title('signal x(n),0<=n<=100');
   axis([0,N,-2.5,2.5]);
Y1=fft(y1);magY1=abs(Y1(1:1:N/2+1));
k1=0:1:N/2;w1=2*pi/N*k1;
subplot(2,1,2);
   title('Samples of DTFT Magnitude');
   stem(w1/pi,magY1); axis([0,1,0,10]);
   xlabel('frequency in pi units');