BP_main.zip_后向散射_后向散射算法_探地雷达_探地雷达成像_雷达 散射 成像

%---------------------------- % A Fast Back -Projection Algorithm % Based on Cross Correlation for % GPR Imaging: : (Lin zhou) % code by fulei jlu % 2012 04 06 % clear;clc % prepar profile data function [xx yy EA]=BP_main(str,epsr,h_antenna,steps_antenna,x_LD,y_LD,x_RU,y_RU,dx,dy,u) [header fields]=gprmax(strcat(str,'.out')); T(:,:)=fields.ez(:,1,:); NS=header.iterations; NT=header.NSteps; dt=header.dt; NN1=5; [st]=DWR(T,NS,NT,dt,NN1); [Mt Nt]=size(st); % constructure imgae position(A) % epsr=4; % h=0.4; h=h_antenna; % steps=0.01; steps=steps_antenna; % x1=0.2;y1=0; % x2=0.8;y2=0.5; % dx=0.005;dy=0.005; x1=x_LD;y1=y_LD; x2=x_RU;y2=y_RU; xx=x1:dx:x2; yy=y1:dy:y2; xk=x1:steps:x2; [M0 N0]=size(xk); [A_x A_z]=meshgrid(xx,yy); [M N]=size(A_x); EA=zeros(size(A_x)); % find xr and computer tao_a,k switch u case 1 for jn=1:M for in=1:N for kn=1:NT tao_ak=findxr(A_x(jn,in),A_z(jn,in),xk(kn),h,epsr); index=fix(tao_ak/dt); if index <Mt u(kn)=(st(index,kn)); end u0=sum(u); end EA(jn,in)=u0; end end case 2 for jn=1:M for in=1:N for kn=1:NT tao_ak=findxr(A_x(jn,in),A_z(jn,in),xk(kn),h,epsr); index=fix(tao_ak/dt); if index <Mt u(kn)=(st(index,kn)); end u0=sum(u); end EA(jn,in)=u0; end end end imagesc(xx,yy,EA);