radar.m

雷达单点成像仿真

clear;
r=3e-2;B=60e6;fs=90e6;prf=60;ls=300;R=50e3;c=3e8;T=2e-6;v=100;ts=ls/(2*v);
pa=r*R/(2*ls);  pr=c/(2*B);  k=B/T;
qt=-T/2:(1/fs):T/2-1/fs;
t=-ts:(1/prf):ts-1/prf;
rt=(R.^2+(v*t).^2).^2;
f=-fs/2:(fs/256):fs/2-fs/256;
hf=exp((i*2*pi*f).^2/(4*pi*k));
lfm=exp(i*pi*k*qt.^2)'*exp(-i*4*pi*rt/r);
[l,L]=size(lfm);
hw1=exp(i*(2*pi*f).^2/(4*pi*k));
ka=-2*v.^2/(r*k);
w=-prf/2:(prf/256):prf/2-prf/256;
hw2=exp(j*w.^2/(4*pi*ka));
s=1:256;
lfm=lfm';
for m=1:L
    s1(m,s)=fft(lfm(m,1:180),256);
    s1(m,s)=fftshift(s1(m,s));
    s1(m,s)=ifft(s1(m,s).*hw1);
    s1(m,s)=ifftshift(s1(m,s));
end
s1=s1';
for k=1:256
          s2(k,s)=fft(s1(k,1:180),256);
          s2(k,s)=fftshift(s2(k,s));
          s2(k,s)=ifft(s2(k,s).*hw2);
          s2(k,s)=ifftshift(s2(k,s));
end
[m,n]=size(s2)
subplot(2,1,1)
contour(abs(s2))
subplot(2,1,2)
mesh(abs(s2))
clear all;