Physical optics (PO) programs version 2.3     

nonGUI Programs:
---------------
pomonostatic.m - monostatic RCS of bodies composed of triangular facets 
pobistatic.m - bistatic RCS of bodies composed of triangular facets

GUI Programs:
------------
pofacets.m - launches GUI windows for: 
mono.m - monostatic RCS of bodies composed of triangular facets and 
bistat.m - bistatic RCS of bodies composed of triangular facets 

Overview:
--------

The theory and operation is described briefly in the Microsoft Word document 
pocodes.doc.  More details are available in the references cited therein.  The 
NPS Masters thesis by Elmo Garrido describes the detailed operation and layout 
of the GUI.

To run either of the above programs from the GUI, type pofacets in the Matlab 
command shell (the pwd of the command shell must be where pofacets.m resides).
Model data files are in the subdirectory models directly below the directory
containing pofacets.m.

For the nonGUI versions, to run either of these codes from the Matlab command 
shell, simply get into the directory in which they reside and type the name.  

When creating a new file with the nonGUI version, create a folder in the 
directory in which pofacets resides.  The name of the folder will be the model 
name. Two files must exist in the folder: facets.m and coordinates.m.  These 
two files can be generated with any text editor.  See the Microsoft Word 
document for some examples.

Notes on the GUI:
----------------

The appearance will depend on the display settings.  Version 2.3 has some changes
that should help keep a uniform appearance throughout the GUI. If the button and 
label print are too large and being clipped, then changing the settings in the 
control panel may help.  The only other solution is to go into each Matlab script 
and change the font or point size in every uicontrol call.

IMPORTANT NOTE ABOUT SAVING FILES:

When saving a newly created file, look for the Save As under File in the view 
model window. The program WILL NOT warn you if you close the coordinates and 
facets windows without saving the entries contained in them.  If you do so all 
the new data will be lost! 

When entering the number of nodes or vertices, hit RETURN to generate the entry 
boxes for the node and vertex data.

When changing any of the target parameters (scale, illumumination, or resistivity)
the data must be resaved.

The GUI will accept only real numbers for Rs, even though the calculations permit
complex Rs.  Complex values of Rs can be "hardwired" by the user by adding 
assignment statements in bistat.m and mono.m.

Currently the number of nodes and facets in a model CANNOT be increased or 
decreased without loosing all of the data.   

Notes:  G.m is a required function
        polardb.m is a polar plotting function (not required) 
        fact.m is a factorial (some versions of Matlab do not have this)

Converting between GUI and nonGUI model file formats:
----------------------------------------------------
The model data is stored in two ASCII files in the nonGUI version: coordinates.m 
and facets.m.  In the GUI version the data is stored in two BINARY files with 
*.mat extensions: coordinates.mat and facet.mat.  The ASCII files can be opened in
the editor and easily modified, but the *.mat files cannot (the Design Model program
must be used).  The programs convert2gui.m and convert2nogui.m are translators that
will convert the data formats.  convert2gui writes *.mat files from the *.m files.
convert2nogui writes *.m files from the *.mat files.

Data directories provided:
-------------------------
Triangles in these data files are ordered in a right-hand sense for the closed
surfaces.  Note that the dimensions of the targets are not all in meters, so
it may be necessary to scale the frequency to obtain realistic RCS values.

longbox
box 
vtail
plate
sidewinder
utd2
chuck
brick

Thanks to the short course and workshop students who provided the models!

Disclamer:
These codes were created for instructional purposes.  Basic test geometries
have been validated, but there is no guarantee of accuracy for other cases.  

6/10/02
(POFACETS version 2.3)