Re: NEC-LIST: current sources

Hi Grant,

I have made a modified version of NEC4 with permit to compute the
complex scalar potential at any point in space. If you chose the point
to be on the surface, or in the volume of the conductor, the program
will give you the complex scalar potential of that conductor.

The scalar potential his calculated using the Lorentz gauge condition
or Int(E+jwA)dl. From the former condition, scalar potential is given
by (V = -div(A) / jwue) for a non-conducting medium and by (V =
-div(A) / u(sig+jwe)) for a lossy medium, where it is assumed that:
Rot(A) = B.

For doing so, I have add several control cards to the program.
Here is a list of some of the control card I have add:

DP difference of complex scalar potential between to near points.
          (Method divergence of A).
DR difference of complex scalar potential between one point and a
reference.
          (Method divergence of A).
LP complex scalar potential along a line according to the equation
Int(E+jwA)dl.
NP complex scalar potential at points in space (x,y,z) (Like NE or NH)
           (Method divergence of A).
PD complex scalar potential along a line (Method divergence of A).

The program can be call by a batch file with a configuration file
giving all the necessary information or by a command line mode with
parameters to be declared in the command line. It use dynamic
allocation of memory, so it adapt itself to the requirement of the
probleme. It works in DOS or a DOS WINDOW in WINDOWS 3.1, WINDOWS 95
or WINDOWS NT.

You can easily define many current sources on the segment of your
choice and the program will calculate the complex scalar potential at
any point of your choice and as many as you want.

If you are interested, just contact me at: dallaire.daniel_at_tnc-inc.qc.ca

Daniel Dallaire

At 04:28 PM 5/26/98 , you wrote:
>Has anyone modified the NEC4 source code to include the matrix math
>required to calculate the complex voltage sources that produce
>specific complex currents at random locations different from the
>voltage source locations? I did this for an early MoM program 20
>years ago, but am loathe to do it to NEC4 because of all the various
>matrix math short-cuts NEC4 uses. Looks at first glance like I might
>be opening a can of worms. But my old program allowed me to specify
>any number of desired complex currents at any segments, and I would
>simply specify the source segment locations, then it would tell me the
>exact values for those sources that would produce the desired
>currents, explicitly, non-iteratively. I used it for pattern
>optimization, broadcast antenna monitor sample loop placement vs
>measured pattern studies, etc.
>
>Grant Bingeman

**************************************
Daniel Dallaire, Ing., M.Sc.A.
President Techno-Cos Inc.

Services de consultation et de recherche scientifique
Interferences et compatibilite electromagnetique

Research and consultation services
Electromagnetic compatibility and interference

C.P. 56, Ste-Julie
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Tel.: +1 (514) 649-5638
Fax.: +1 (514) 649-9272
E-mail: <dallaire.daniel_at_tnc-inc.qc.ca>
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Received on Thu May 28 1998 - 10:18:30 EDT