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diff --git a/openEMS/matlab/Tutorials/Patch_Antenna_Array.m b/openEMS/matlab/Tutorials/Patch_Antenna_Array.m
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+function [port nf2ff] = Patch_Antenna_Array(Sim_Path, postproc_only, show_structure, xpos, caps, resist, active )
+% [port nf2ff] = Patch_Antenna_Array(Sim_Path, postproc_only, show_structure, xpos, caps, resist, active )
+%
+% Script to setup the patch array as described in [1].
+% Run main script in Patch_Antenna_Phased_Array.m instead!
+%
+% Sim_Path: Simulation path
+% postproc_only: set to post process only 0/1
+% show_structure: show the strucuture in AppCSXCAD 0/1
+% xpos: the x-position for each antenna is defined
+% caps: the port capacity (will override active port)
+% resist: port resitance
+% active: switch port active
+%
+% References:
+% [1] Y. Yusuf and X. Gong, “A low-cost patch antenna phased array with
+%   analog beam steering using mutual coupling and reactive loading,” IEEE
+%   Antennas Wireless Propag. Lett., vol. 7, pp. 81–84, 2008.
+%
+% Tested with
+%  - Matlab 2011a
+%  - openEMS v0.0.31
+%
+% (C) 2013 Thorsten Liebig <thorsten.liebig@gmx.de>
+
+% example
+% xpos = [-41 0 41];
+% caps = [0.2e-12 0 0.2e-12];
+% active = [0 1 0];
+% resist = [50 50 50];
+
+%% setup the simulation
+physical_constants;
+unit = 1e-3; % all length in mm
+
+% patch geometry setup
+patch.W  = 35;  % width
+patch.L = 28.3; % length
+patch.Ws = 3.8; % width of feeding stub
+patch.Gs = 1;   % width of feeding gab
+patch.l = 6;    % length of feeding stub
+patch.y0 = 10;  % depth of feeding stub into into patch
+
+% patch resonance frequency
+f0 = 3e9;
+
+%substrate setup
+substrate.name = 'Ro3003';
+substrate.epsR   = 3;
+substrate.kappa  = 0.0013 * 2*pi*f0 * EPS0*substrate.epsR;
+substrate.thickness = 1.524;
+substrate.cells = 4;
+
+substrate.width = patch.W + max(xpos) - min(xpos) + 4*patch.l;
+substrate.length = 3*patch.l + patch.L;
+
+% size of the simulation box
+AirSpacer = [50 50 30];
+
+edge_res = [-1/3 2/3]*1;
+
+%% setup FDTD parameter & excitation function
+fc = 2e9; % 20 dB corner frequency
+FDTD = InitFDTD( 'EndCriteria', 1e-4 );
+FDTD = SetGaussExcite( FDTD, f0, fc );
+BC = [1 1 1 1 1 1]*3;
+FDTD = SetBoundaryCond( FDTD, BC );
+
+%% setup CSXCAD geometry & mesh
+CSX = InitCSX();
+
+mesh.x = [];
+mesh.y = [];
+mesh.z = [];
+
+%% create patch
+CSX = AddMetal( CSX, 'patch' ); % create a perfect electric conductor (PEC)
+
+for port_nr=1:numel(xpos)
+    start = [xpos(port_nr)-patch.W/2           patch.l         substrate.thickness];
+    stop  = [xpos(port_nr)-patch.Ws/2-patch.Gs patch.l+patch.L substrate.thickness];
+    CSX = AddBox(CSX,'patch',10, start, stop);
+    mesh.x = [mesh.x xpos(port_nr)-patch.W/2-edge_res];
+
+    start = [xpos(port_nr)+patch.W/2           patch.l         substrate.thickness];
+    stop  = [xpos(port_nr)+patch.Ws/2+patch.Gs patch.l+patch.L substrate.thickness];
+    CSX = AddBox(CSX,'patch',10, start, stop);
+    mesh.x = [mesh.x xpos(port_nr)+patch.W/2+edge_res];
+
+    mesh.y = [mesh.y patch.l-edge_res patch.l+patch.L+edge_res];
+
+    start = [xpos(port_nr)-patch.Ws/2-patch.Gs patch.l+patch.y0 substrate.thickness];
+    stop  = [xpos(port_nr)+patch.Ws/2+patch.Gs patch.l+patch.L  substrate.thickness];
+    CSX = AddBox(CSX,'patch',10, start, stop);
+
+    % feed line
+    start = [xpos(port_nr)-patch.Ws/2 patch.l+patch.y0 substrate.thickness];
+    stop  = [xpos(port_nr)+patch.Ws/2 0                substrate.thickness];
+    CSX = AddBox(CSX,'patch',10, start, stop);
+
+    mesh.x = [mesh.x xpos(port_nr)+linspace(-patch.Ws/2-patch.Gs,-patch.Ws/2,3) xpos(port_nr)+linspace(patch.Ws/2,patch.Ws/2+patch.Gs,3)];
+
+    start = [xpos(port_nr)-patch.Ws/2 0 0];
+    stop  = [xpos(port_nr)+patch.Ws/2 0 substrate.thickness];
+    if (caps(port_nr)>0)
+        CSX = AddLumpedElement(CSX, ['C_' num2str(port_nr)], 2, 'C', caps(port_nr));
+        CSX = AddBox(CSX,['C_' num2str(port_nr)],10, start, stop);
+
+        [CSX port{port_nr}] = AddLumpedPort(CSX, 5 ,port_nr ,inf, start, stop, [0 0 1], 0);
+    else
+        % feed port
+        [CSX port{port_nr}] = AddLumpedPort(CSX, 5 ,port_nr, resist(port_nr), start, stop, [0 0 1], active(port_nr));
+    end
+end
+
+%% create substrate
+CSX = AddMaterial( CSX, substrate.name );
+CSX = SetMaterialProperty( CSX, substrate.name, 'Epsilon', substrate.epsR, 'Kappa', substrate.kappa );
+start = [-substrate.width/2 0                0];
+stop  = [ substrate.width/2 substrate.length substrate.thickness];
+CSX = AddBox( CSX, substrate.name, 0, start, stop );
+
+mesh.x = [mesh.x start(1) stop(1)];
+mesh.y = [mesh.y start(2) stop(2)];
+
+% add extra cells to discretize the substrate thickness
+mesh.z = [linspace(0,substrate.thickness,substrate.cells+1) mesh.z];
+
+%% create ground (same size as substrate)
+CSX = AddMetal( CSX, 'gnd' ); % create a perfect electric conductor (PEC)
+start(3)=0;
+stop(3) =0;
+CSX = AddBox(CSX,'gnd',10,start,stop);
+
+%% finalize the mesh
+% generate a smooth mesh with max. cell size: lambda_min / 20
+mesh = SmoothMesh(mesh, 2, 1.3);
+mesh.x = [mesh.x min(mesh.x)-AirSpacer(1) max(mesh.x)+AirSpacer(1)];
+mesh.y = [mesh.y min(mesh.y)-AirSpacer(2) max(mesh.y)+AirSpacer(2)];
+mesh.z = [mesh.z min(mesh.z)-AirSpacer(3) max(mesh.z)+2*AirSpacer(3)];
+
+mesh = SmoothMesh(mesh, c0 / (f0+fc) / unit / 20, 1.3);
+
+%% add a nf2ff calc box; size is 3 cells away from MUR boundary condition
+start = [mesh.x(4)     mesh.y(4)     mesh.z(4)];
+stop  = [mesh.x(end-3) mesh.y(end-3) mesh.z(end-3)];
+[CSX nf2ff] = CreateNF2FFBox(CSX, 'nf2ff', start, stop);
+
+mesh = AddPML(mesh,(BC==3)*8);
+CSX = DefineRectGrid(CSX, unit, mesh);
+
+%% prepare simulation folder
+Sim_CSX = 'patch_array.xml';
+
+if (postproc_only==0)
+    [status, message, messageid] = rmdir( Sim_Path, 's' ); % clear previous directory
+    [status, message, messageid] = mkdir( Sim_Path ); % create empty simulation folder
+
+    %% write openEMS compatible xml-file
+    WriteOpenEMS( [Sim_Path '/' Sim_CSX], FDTD, CSX );
+
+    %% show the structure
+    if (show_structure>0)
+        CSXGeomPlot( [Sim_Path '/' Sim_CSX] );
+    end
+
+    %% run openEMS
+    RunOpenEMS( Sim_Path, Sim_CSX);
+end
+