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Simulators >> RF Simulators >> Problem with ADS MCLIN !
https://designers-guide.org/forum/YaBB.pl?num=1265012932

Message started by kennycs on Feb 1^st, 2010, 12:28am

Title: Problem with ADS MCLIN !
Post by kennycs on Feb 1^st, 2010, 12:28am

When I use S-parameter simulate with MCLIN(differential lines) in ADS, the result |S11|,|S21| seems wrong. I think |S21| should be monotone decreasing ,But the result shows it is periodic ,I'm confused!
Thanks!

Title: Re: Problem with ADS MCLIN !
Post by pancho_hideboo on Feb 1^st, 2010, 1:41am

kennycs wrote on Feb 1^st, 2010, 12:28am:

When I use S-parameter simulate with MCLIN(differential lines) in ADS,
the result |S11|,|S21| seems wrong.
I think |S21| should be monotone decreasing, But the result shows it is periodic

It is natural result since your line is lossless.
Frequency characteristics of lossless line is periodic.

Why do you think |S21| decrease monotonically ?

Consider |S21| of lossless single line.
Does |S21| decrease regarding frequency ?

For coupled line, if you pay attention to one line, another line acts as resonator.
So periodicity of |S21| is natural.

Title: Re: Problem with ADS MCLIN !
Post by kennycs on Feb 1^st, 2010, 7:12pm

pancho_hideboo wrote on Feb 1^st, 2010, 1:41am:

kennycs wrote on Feb 1^st, 2010, 12:28am:

When I use S-parameter simulate with MCLIN(differential lines) in ADS,
the result |S11|,|S21| seems wrong.
I think |S21| should be monotone decreasing, But the result shows it is periodic

Thank you very much, I got the reason. :D