数字信号处理实验的代码,仅参考

grid on;

subplot(4,2,2);

plot(W/(2*pi*1000),Xa*1000); ylabel('Xa(w)'); grid on; Ts1=0.0002; n1=-25:1:25;

x1=exp(-1000*abs(n1*Ts1)); Ts2=0.001; n2=-5:1:5;

x2=exp(-1000*abs(n2*Ts2)); N=500; k=0:1:N; w=pi*k/N;

X1=x1*exp(-j*n1'*w); X1=real(X1);

X2=x2*exp(-j*n2'*w); X2=real(X2);

w=[-fliplr(w),w(2:N+1)]; X1=[fliplr(X1),X1(2:N+1)]; X2=[fliplr(X2),X2(2:N+1)]; subplot(4,2,3);

stem(n1*Ts1*1000,x1); ylabel('x1(n)');

legend('抽样频率f1='); grid on;

subplot(4,2,4); plot(w/pi,X1); ylabel('X1(w)'); grid on;

subplot(4,2,5);

stem(n2*Ts2*1000,x2); ylabel('x2(n)');

legend('抽样频率f2='); subplot(4,2,6); plot(w/pi,X2); ylabel('X2(w)'); Fs1=1/Ts1; nTs1=n1*Ts1;

xa1=x1*sinc(Fs1*(ones(length(n1),1)*t-nTs1'*ones(1,length(t)))); subplot(4,2,7); plot(t*1000,xa1); ylabel('xa1(t)'); grid on;