Question

matlab画图的问题、、

t=-10:0.00001:10;
w=-20000:0.1:20000;
Id=17;
fc=1000+100*Id;
w0=100*pi;
wc=2*pi*fc;
f=0.05*sin(w0*t)./(w0*t);
f1=f.*cos(wc*t);
f2=100*f1;
f3=f2.*cos(wc*t);
F=pi/w0*(u(w+w0)-u(w-w0));
F1=100*0.5*pi/w0*(u(w+wc+w0)-u(w+wc-w0)+u(w-wc+w0)-u(w-wc-w0));
F2=100*0.5*pi/w0*(u(w+w0)-u(w-w0))+100*0.25*pi/w0*(u(w+2*wc+w0)-u(w+2*wc-w0)+u(w-2*wc+w0)-u(w-2*wc-w0));
subplot(231);
plot(t,f);
xlabel('x');
axis([-0.1,0.1,-0.1,0.1])
title('调制信号波形');
subplot(232);
plot(t,f2);
xlabel('x');
axis([-0.01,0.01,-10,10]) ;
title('已调信号波形');
subplot(233);
plot(t,f3);
xlabel('x');
axis([-0.01,0.01,-10,10]) ;
title('解调信号波形');
subplot(234);
xlabel('w');
plot(w,F);
axis([-500,500,0,0.015]);
title('调制信号频谱');
subplot(235);
xlabel('w');
plot(w,F1);
axis([-20000,20000,0,1]);
title('已调信号频谱');
subplot(236);
xlabel('w');
plot(w,F2);
axis([-100000,100000,0,1]);

title('解调信号频谱');
为什么最后一幅图不对呢。应该还有两个小的图啊、、、

Answer 1

http://www.21ic.com/jszt/matlab.htmMATLAB各种资料，教程。。有需要可以看一下。