Copyright: 1996 - 2024
BSEE - KB3UON
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
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design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
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coupled microstrip lines - RF Cafe Forums
RF Cafe Forums closed its virtual doors in 2012 mainly due to other social media
platforms dominating public commenting venues. RF Cafe Forums began sometime around
August of 2003 and was quite well-attended for many years. By 2010, Facebook and
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Forums activity dropped off precipitously. If the folks at
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but until then it is probably not worth the effort. Regardless, there are still
lots of great posts in the archive that ware worth looking at.
Below are the old forum threads, including responses to the original posts.
|-- Amateur Radio
Gripes & Humor
-- CAE, CAD, &
Test & Measurement
Post subject: coupled microstrip lines
Mon May 24, 2004 2:09 pm
May 24, 2004 1:56 pm
Location: Moorestown, NJ
anyone have any tricks for optimizing coupled microstrip lines for differential
mode (Zodd=50ohms, Zeven=100ohms)? I find that the closed form models
in ADS and AWR do not match what is produced in Sonnet or Momentum.
Thanks for any help,
Unread postPosted: Tue May 25, 2004
Sonnet and Momentum are "2.5D" simulators, the conductors
must be zero thickness. Are you accounting for this? Momentum lets you
define conductor thickness only for signal attenuation calculations
not for geometric impact on electrical performance. Finite conductor
thickness will have an effect on the odd mode impedance.
understanding, the "closed form" solver in LineCalc of ADS is a curve
match to emperical and 3D simulated data for coupled lines. I have found
it to be accurate enough for most edge coupled filters, as well as much
faster than a MOM solver.
Unread postPosted: Tue Jun 01, 2004 2:47 am
The differential issue does not work properly in AWR. Sonnet
seems to be closer. anyway, measure and compare it.
I came to 98%
agreement with hand-calculation on 200ohm diff TL. The vector analyzer
measure single ended parameters, then it converts to diff. Do you want
the formula for conversion?