radar2.m

雷达一个点仿真

clear;
Lw=0.03;
B=60e6;
T=2e-6;
k=B/T;
fs=90e6;
t=-T/2:1/fs:T/2-1/fs;
RPF=60;
R=50e3;
v=100;
Ts=3;
t1=-Ts/2:1/RPF:Ts/2-1/RPF;
w=-fs*pi*2/2:fs*pi*2/256:fs*pi*2/2-fs*pi*2/256;
rt=(R*R+(v*t1).^2).^(1/2);
 LFM=exp(i*pi*k*t.^2);
 DOP=exp(-(j*4*pi*rt)/Lw);
 LFM=DOP'*LFM
l=1:length(t);
L=1:256;
for m=1:180;
    f(m,L)=fft(LFM(m,l),256);
    f(m,L)=fftshift(f(m,L));
    f(m,L)=f(m,L).*exp(i*w.^2/(4*pi*k));
    f(m,L)=ifft(f(m,L));
    f(m,L)=ifftshift(f(m,L));
end
ka=-(2*v*v)/(Lw*R);
L=1:256;
wd=-RPF*2*pi/2:RPF*2*pi/256:RPF*2*pi/2-RPF*2*pi/256;
for m=1:256
    f(L,m)=fft(f(1:180,m),256);
    f(L,m)=fftshift(f(L,m));
    f(L,m)=f(L,m).*(exp((i*wd.^2/(4*pi*ka))))';
    f(L,m)=ifft(f(L,m));
    f(L,m)=ifftshift(f(L,m));
end
 subplot(2,1,1);
contour(abs(f));%等高线图，要放大看
subplot(2,1,2);
mesh(abs(f));  %三维图
clear all;