RE: Modeling - Fast Tr

Brian C. Wadell (bcwadell@mailserver2.tiac.net)
Thu, 5 Sep 1996 22:48:17 -0400

Fred,

FYI, s-parameters are often used for nonlinear devices by specifying an =
operating point. The s-parameters are taken at various operating points =
and the actual operating point is interpolated among the available data. =
For example, for a transistor you might take s-parameters for different =
collector currents.

This is not a valid technique for strong nonlinearities but is very =
useful in many practical cases.

Nonlinear s-parameters do exist. They are called VIOMAP. Basically a =
Volterra series version of linear s-parameters.

Regards,

Brian C. Wadell
Guided Wave Solutions
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range and convert these into useful models that are ideal to use in a =
non linear
simulator such as Spice. And....S parameters DO CONTAIN INFORMATION =
ABOUT COUPLING if the
measurement instruments can measure n-ports. S parameters cannot be =
applied to the
digital switching transistors because of their non-linearities.=20

Best Regards,

Fred Balistreri