www.pudn.com > programradarsystemdisign.zip > fig5_14.m

% use this program to reproduce Fig. 5.14 of text 
clear all 
eps = 1.5e-5; 
t = 0:0.001:.5;                  
y = chirp(t,0,.25,20); 
figure(1) 
plot(t,y); 
yfft = fft(y,512) ; 
ycomp = fftshift(abs(ifft(yfft .* conj(yfft)))); 
maxval = max (ycomp); 
ycomp = eps + ycomp ./ maxval;  
figure(1) 
del = .5 /512.; 
tt = 0:del:.5-eps; 
plot (tt,ycomp,'k') 
axis tight 
xlabel ('Relative delay - seconds'); 
ylabel('Normalized compressed pulse') 
grid 
%change center frequency 
y1 = chirp (t,0,.25,21); 
y1fft = fft(y1,512); 
y1comp = fftshift(abs(ifft(y1fft .* conj(yfft)))); 
maxval = max (y1comp); 
y1comp = eps + y1comp ./ maxval;  
figure(2) 
plot (tt,y1comp,'k') 
axis tight 
xlabel ('Relative delay - seconds'); 
ylabel('Normalized compressed pulse') 
grid 
%change pulse width 
t = 0:0.001:.45;                  
y2 = chirp (t,0,.225,20); 
y2fft = fft(y2,512); 
y2comp = fftshift(abs(ifft(y2fft .* conj(yfft)))); 
maxval = max (y2comp); 
y2comp = eps + y2comp ./ maxval;  
figure(3) 
plot (tt,y2comp,'k') 
axis tight 
xlabel ('Relative delay - seconds'); 
ylabel('Normalized compressed pulse') 
grid