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Panel Controls
The Panel for Thin Wire Scattering provides five input controls
to adjust properties of the incident field and scattering object.
Results are provided through three output boxes and the two plot panels.
Input Controls

Wire Length in cm and Wire Radius in cm
Two typein boxes set the size of the scattering wire in centimeters.
The wire
is aligned along the z axis. You can type in any numeric
value for length and radius. Entries must be positive decimal numbers.
You must click Solve for these values to take effect.
The condition for validity of the calculated results is only that
wavelength of incident wave is large compared to the radius. Results
are valid for any length of wire if sufficiently many Basis functions
are used. (See Number of functions below.)

Number of Functions
This selects the number of piecewise sinsusoidal current basis functions
used along the wire. Increasing this will give a more accurate
current, but will take more time to compute. Excessively large number of
basis functions (e.g. more than 20,000) can lead to numerical instabilities.
You must click Solve for this value to take effect.

Frequency in MHz
This sets the frequency of the incoming plane wave in MegaHertz.
You must click Solve for this value to take effect.

Incident Angle
This slide bar sets
the incident angle defined so that its cosine is the dot product
of the incident propagation direction with the zaxis.
Changing this
value will display results with various incident angles.
Note the polarization is always assumed to be in the plane defined
by the propagation direction and the wire. The thin wire approximation
neglects the scattering of the other polarization.
Output Boxes

Total Cross Section
This is an output result. It is the usual total power radiated divided
by the incident flux. The result is in cm^{2}.

Radar Cross Section
Radar Cross Section
is also called the monostatic radar cross section in the
engineering literature. It is the differential backscatter cross section
(i. e. evaluated at theta=pitheta incident) per solid angle multiplied by 4 pi.

Solve and Stop
Clicking Solve is necessary to fill the impedance matrix. The
Stop button will be disabled except when calculating.
Clicking Stop will cancel the current calculation.

Blank Panel to the right of Solve
This panel is used for messages if bad input is given. Try setting
the wire length to 1 or nonumeric input to see it work.
For more detail please see the HTML or Tex versions of the user
manual distributed with this software.
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