mti_fft8.m

这是雷达动目标检测的matlab实现方法

clear;
clc;
close all;
fr=1.6e3;%脉冲重复频率
tr=1/fr;%脉冲重复周期
fs=1e6;%采样频率
ts=1/fs;%采样周期

f_doppler=800;%多普勒频率

t=0:1/fs:tr-1/fs;%一个脉冲重复时间轴

x=ones(1,2);%回波中目标的回波

n=length(x);
N=fs/fr;
x_1=[zeros(1,120),x,zeros(1,N-120-n)];%一个脉冲回波
x_10=repmat(x_1,1,10);%10个脉冲回波,其中两个为填充脉冲,一个相关处理间隔为10*tr
t_10=(0:length(x_10)-1)*ts;
s_doppler=exp(j*2*pi*f_doppler*t_10);%多普勒调制信号
 %s_doppler=cos(2*pi*f_doppler*t_10);%多普勒调制信号
randn('state', sum(100*clock));%Initialize randn to a different state each time
s_noise_i=0.1*randn(1,length(s_doppler));
randn('state', sum(100*clock));%Initialize randn to a different state each time
s_noise_q=0.1*randn(1,length(s_doppler));
y=x_10.*s_doppler+s_noise_i+s_noise_q*j;%附带多普勒的动目标回波
 %y=x_10;
 subplot(211)
 plot(t_10,real(y));
 subplot(212)
 plot(t_10,imag(y));
%%%%%%%%%%%%%%固定杂波对消处理%%%%%%%%%%%%%%%%%%%%
yt=reshape(y,length(y)/10,10)';
for i=1:8
      s_mti(i,:)=yt(i,:)+yt(i+2,:)-2*yt(i+1,:);%三脉冲对消
%      s_mti(i,:)=yt(i,:)-yt(i+1,:);%两脉冲对消
end
% s_mti=s_mti/max(max(s_mti));
% s_mti=yt(1:8,:);
%%%%%%%%%%%%%%%%%%%%采用FFT进行MTD处理%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
M=8;
L=length(s_mti);
for i=1:L
    % s_temp=s_mti(:,i);%不加权
  s_temp=s_mti(:,i).*hamming(M);%Hamming 加权FFT
  %     s_temp=s_mti(:,i).*chebwin(M);%切比雪夫 加权FFT
    s_mtd(:,i)=fft(s_temp,M);
end;
figure
t=0:ts:(length(s_mtd)-1)*ts;
subplot(241),plot(t,abs(s_mtd(1,:))),title('（第0通道）');
subplot(242),plot(t,abs(s_mtd(2,:))),title('（第1通道）');
subplot(243),plot(t,abs(s_mtd(3,:))),title('（第2通道）');
subplot(244),plot(t,abs(s_mtd(4,:))),title('（第3通道）');
subplot(245),plot(t,abs(s_mtd(5,:))),title('（第4通道）');
subplot(246),plot(t,abs(s_mtd(6,:))),title('（第5通道）');
subplot(247),plot(t,abs(s_mtd(7,:))),title('（第6通道）');
subplot(248),plot(t,abs(s_mtd(8,:))),title('（第7通道）');

figure
plot(max(abs(s_mtd)))
figure
plot(0:7,(max(abs(s_mtd'))))