sinky.m

进行ISAR运动补偿的程序 kylsdone 方法来消除越距离单元走动,注释完整

function [s,V] = sinky(z,rho,theta)
% function SINKY.M
% Shannon reconstruction algorithm
%
% Usage: [s,V]=sinky(z,rho,theta)
% Where: z=M by N matrix with samples in frequency domain
% rho,theta=radius and angles of data points
% s=interpolated matrix
% V=vector that includes [X0 dkx dky fl]

% Variables
bursts=size(z,1); pul_burst=size(z,2);
thetav=theta(:,1).'; dtheta=thetav(2)-theta(1);
ac = max(thetav) - min(thetav);
ca = (max(thetav) + min(thetav)) / 2;
rho = rho .* (4 * pi / 3e8);	     %% frequency matrix in rad/mt
rhov = rho(1,:); X0=pi/(rhov(2)-rhov(1));
rhoc = linspace(min(rhov), max(rhov) * cos(ac / 2), pul_burst);
drho=rhov(2)-rhov(1); s=zeros(size(rho)); s2=s;

% Interpolation in X direction
close all; flops(0); dx=drho; dkx=dx;
for a=1:length(thetav),a
   rhox=rhoc./cos(thetav(a)-ca);
   for n=1:length(rhox),
      arg=rhox(n)*ones(1,length(rhox))-rhov;
      s(a,n)=sum(z(a,:).*sinc(arg/dx));
end;end;

% Interpolation in Y direction
a=rhoc(1)*tan(min(thetav)-ca);
n=rhoc(1)*tan(max(thetav)-ca);
rhoyi=linspace(a,n,length(thetav));
dy=rhoyi(2)-rhoyi(1); dky=dy;
for a=1:length(rhoc),a
   rhoyd=rhoc(a).*tan(thetav-ca);
   for n=1:length(thetav),
      arg=rhoyi(n)*ones(1,length(rhoyd))-rhoyd;
      s2(n,a)=sum((s(:,a).').*sinc(arg/dy));
end;end;
s=s2; fl=flops

V=[X0 dkx dky fl];