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tutorial: added RCS calculations to RCS_Sphere example 

This still needs testing and validation!

Signed-off-by: Thorsten Liebig <Thorsten.Liebig@gmx.de>
pull/1/head
Thorsten Liebig 2012-07-18 16:04:05 +02:00
parent ef8ef75032
commit e4eee538d6
1 changed files with 32 additions and 4 deletions
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36
matlab/Tutorials/RCS_Sphere.m
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@ -1,8 +1,6 @@
% %
% Tutorials / radar cross section of a metal sphere % Tutorials / radar cross section of a metal sphere
% %
% This tutorial is unfinished!
%
% Describtion at: % Describtion at:
% http://openems.de/index.php/Tutorial:_RCS_Sphere % http://openems.de/index.php/Tutorial:_RCS_Sphere
% %
@ -20,11 +18,11 @@ clc
physical_constants; physical_constants;
unit = 1e-3; % all length in mm unit = 1e-3; % all length in mm
sphere.rad = 160; sphere.rad = 200;
% size of the simulation box % size of the simulation box
SimBox = 1000; SimBox = 1000;
PW_Box = 500; PW_Box = 750;
%% setup FDTD parameter & excitation function %% setup FDTD parameter & excitation function
f_start = 200e6; % start frequency f_start = 200e6; % start frequency
@ -64,6 +62,11 @@ start = [mesh.x(1) mesh.y(1) 0];
stop = [mesh.x(end) mesh.y(end) 0]; stop = [mesh.x(end) mesh.y(end) 0];
CSX = AddBox(CSX, 'Et', 0, start, stop); CSX = AddBox(CSX, 'Et', 0, start, stop);
%%nf2ff calc
start = [mesh.x(1) mesh.y(1) mesh.z(1)];
stop = [mesh.x(end) mesh.y(end) mesh.z(end)];
[CSX nf2ff] = CreateNF2FFBox(CSX, 'nf2ff', start, stop);
% add 8 lines in all direction as pml spacing % add 8 lines in all direction as pml spacing
mesh = AddPML(mesh,8); mesh = AddPML(mesh,8);
@ -87,3 +90,28 @@ RunOpenEMS( Sim_Path, Sim_CSX);
%% %%
disp('Use Paraview to display the elctric fields dumped by openEMS'); disp('Use Paraview to display the elctric fields dumped by openEMS');
%%
freq = 500e6;
EF = ReadUI( 'et', Sim_Path, freq ); % time domain/freq domain voltage
Pin = 0.5*norm(E_dir)^2/Z0 .* abs(EF.FD{1}.val).^2;
%%
nf2ff = CalcNF2FF(nf2ff, Sim_Path, freq, [-180:2:180]*pi/180, [0 90]*pi/180,'Mode',1);
RCS = 4*pi./Pin(1).*nf2ff.P_rad{1}(:,1);
polar(nf2ff.theta,RCS);
xlabel('z -->');
ylabel('x -->');
hold on
grid on
%%
disp( 'calculating 3D far field pattern and dumping to vtk (use Paraview to visualize)...' );
thetaRange = (0:2:180);
phiRange = (0:2:360) - 180;
nf2ff = CalcNF2FF(nf2ff, Sim_Path, freq, thetaRange*pi/180, phiRange*pi/180,'Verbose',1,'Outfile','3D_Pattern.h5','Mode',1);
RCS = 4*pi./Pin(1).*nf2ff.P_rad{1};
DumpFF2VTK([Sim_Path '/3D_Pattern.vtk'],RCS,thetaRange,phiRange,1e-3);
disp('Use Paraview to display the 3D scattering pattern');