Re: Bird 28.2 - Comments and Suggestions

My response to Stephen Peter's comments:

>>> When I looked at the acadimic and technical
>>> papers on the subject (not to mention the software
>>> we use in house) the off-diagonal elements are
>>> always positive quanities. For what ever reason
>>> this seems to be the convention and I don't see a need
>>> to do it differently.

There is no standard convention. I can give many references
published in technical journals, in which off-diagonal elements
of the C matrix are given as negative numbers. Following are
few examples:
Colin Gordon, Thomas Blazeck and Raj Mittra, "Time-Domain
Simulation of Multiconductor Transmission Lines with
Frequency-Dependent Losses", pp. 1372-1387, IEEE Trans.
on Computer-Aided Design, Vol. 11, No. 11, November 1992.
Tak Tang, Michel Nakhla and Richard Griffith, "Analysis
of Lossy Multiconductor Lines using the Asymptotic Waveform
Evaluation Technique", IEEE Trans. of Microwave Theory and
Techniques, pp. 2107-2116, Vol. 39, No. 12, December 1991.
A.J.Gruodis and C.S.Chang, "Coupled Lossy Transmission Line
Characterization and Simulation", IBM Journal of Res. Develop.,
pp. 25-41, Vol. 25, No. 1, January 1981.

In my opinion, why hide the fact that they are negative ?
Why not just specify them as they are ?

>>> Good point. I did not include a 'G' parameter
>>> because the current IBIS 2.1 Matrix descriptions
>>> do not include one and I was trying to limit the
>>> scope of the bird. If the committe did want
>>> to add the a conductance parameter it could be
>>> in a seperate proposal.
>>>
 
Why add more delay and more paperwork ?
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Dileep Divekar
Contec CAE, Ltd.
2188 Bering Drive
San Jose, CA 95131

Phone - (408)-434-6767 x 126
Fax - (408)-434-6884
Email - dileep@contec.com
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Received on Thu Aug 24 12:56:40 1995