I'm not sure exactly what your looking for here, but for microwave-
millimeterwave
simulations there are a number of programs available.  Simulation of strucutres
like waveguides and antennas can be run on finite element code- primarily we use
HP's HFSS (high freq. structure simulator), but Ansoft also has a similar
program.
For more planar structures (surface micromachined devices) such as switches
airbridges, etc. finite element codes tend to break down due to large aspect
ratios.

I have heard that FDTD (finite difference time domain?) codes can handle these
simulations, but I am not very familiar with these.  We have been using moment
of
method simulators such as HP's momentum, and Sonnet (not sure of the
manufacuterer).

In most cases they seem to be relativelly accurate if you set everything up
right,
but
I have yet to do a thourough study of this pending device fabrication.

All of the above are RF simulation tools and only provide EM simulation and
results.

Electromechanical simulation of the MEMS device must be done separately.

Hope this is helpful.

-rob

Fabio Coccetti wrote:

>  Hallo Everybody,
>
>  -Could you tell me which simulation tools are in use to study the RF
paramiters
>  (Scattering Paramiters ) of HF MEMS devices ?
>
>  -Are they finite difference methods based ?
>
>  -Has anyboby some suggestion on which numerical way to persue such results ?
>
>  THANKS A LOT
>
>  Fabio



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Capt. J. Robert Reid, PhD
Air Force Research Laboratory
Hanscom Research Site

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