武汉理工大学信号与系统实验答案.docx

武汉理工大学信号与系统实验答案
clear
close all
dt=;( dt=;)
t=-2:dt:2;
x=sin(2*pi*t);
plot(t,x Columns 7 through 12
- - + - - +
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Columns 13 through 18
+ - - + - +
- - -
Columns 19 through 21
- - + +
3-2
b=input('b=');
a=input('a=');
[H,w]=freqs(b,a);
Hm=abs(H);
phai=angle(H);
hr=real(H);
Hi=imag(H);
subplot(221)
plot(w,Hm)
grid on
title('Magnitude response');
xlabel('Frequency in rad/sec');
subplot(223)
plot(w,phai)
grid on
title('Phase response')
xlabel('Frequency in rad/sec');
subplot(222)
plot(w,hr),
grid on
title('Real part of frequency response')
xlabel('Frequency in rad/sec');
subplot(224)
plot(w,Hi),
grid on
title('Imaginary part of frequency response') xlabel('Frequency in rad/sec');
运行过程：
1．b=[1,0]
a=[1,1,25]

2．
b=[1,-1]
a=[1,1]

3．
b=[262]
a=[1,10,48,148,306,401,262]

4-1
clear
close all
a=-0::5;
b=-20::20;
[a,b]=meshgrid(a,b);
c=a+i*b;
c=(1-exp(-2*(c+eps)))./(c+eps);
c=abs(c);
subplot(211)
mesh(a,b,c);
surf(a,b,c);
view(-60,20)
axis([0,5,-20,20,0,2]);
title('The Laplace transform of the rectangular pulse'); w=-20::20;
Fw=(2*sin(w+eps).*exp(i*(w+eps)))./(w+eps); subplot(212)
plot(w,abs(Fw))
title('The Fourier transform of the rectangular pulse')
xlabel ('Frequency w')

4-2
clear
close all
b=[0,1/16,0,1];
a=[1,2,2,1];
splane(b,a)
title('The zero-pole diagram') 附：
funct