[SI-LIST] "dominant" losses
- From: "Loyer, Jeff" <jeff.loyer@xxxxxxxxx>
- To: <si-list@xxxxxxxxxxxxx>
- Date: Tue, 25 Nov 2003 08:25:02 -0800
I would like to clarify something - a matter of what "dominant" implies.
In threads discussing losses, we speak of skin effect "dominating" over
dielectric losses (or vice-versa). To me, this gives the impression
that the "dominant" loss (be it skin effect or dielectric for the
frequency of interest) is the only one to consider - that the "minor"
loss (or whatever the opposite of dominant is) is orders of magnitude
less, and can perhaps be neglected. I don't believe that's the case.
For instance, I put together a simple simulation to demonstrate the
losses in a typical stackup. In this simple simulation, at 6 GHz, the
skin effect by itself lowers the signal amplitude by 20%, and the
dielectric loss by itself lowers it by ~28%. The total loss, with both
effects, is 40% (at 6GHz). By the way, for this simulation, the losses
became equal at about 2.5GHz.
My question is, am I the only one who construes the term "dominates" to
imply that the other term is insignificant? Do others understand
"dominant" to mean that it is merely greater than the other term (which
is more in-line with Webster)?
I would lean towards speaking of one loss factor being greater, equal
to, or less than the other, but not "dominant". I personally would
reserve "dominant" for cases where the other factor can be considered
negligible. But perhaps I was mislead somewhere along my academic
path...
Maybe picking at nits, but don't want misperceptions about what factors
can be neglected.
Jeff Loyer
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List technical documents are available at:
http://www.si-list.org
List archives are viewable at:
//www.freelists.org/archives/si-list
or at our remote archives:
http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
Other related posts:
