The Designer's Guide Community Forum

The Designer's Guide Community Forum
https://designers-guide.org/forum/YaBB.pl
Design >> RF Design >> getting incorrect s-parameters (S21 & S12) for LNA design
https://designers-guide.org/forum/YaBB.pl?num=1516253380

Message started by Sagar Juneja on Jan 17^th, 2018, 9:29pm

Title: getting incorrect s-parameters (S21 & S12) for LNA design
Post by Sagar Juneja on Jan 17^th, 2018, 9:29pm

I am designing LNA for GPS (1.57Ghz), i am getting reasonable S11 and S22 = -10dB and -14dB respectively but my S21 is always coming as equal to S12 (i.e. S12 = S21 = -3dB).
Attached is my circuit.

Can somebody advise what could possibly be wrong.

I am designing using Cadence Virtuoso 180nm tool

Title: Re: getting incorrect s-parameters (S21 & S12) for LNA design
Post by anonymus on Jan 17^th, 2018, 10:31pm

I attached a pdf here which might help you, because the deign is looking similar check it once.