Simple LNA and LC matching circuits

Hi All,

I've problematic case related to design of matching circuits connected to the input and output of LNA amplifier. I try to design simple LC circuits on 24 GHz by using calculators avaiable on internet (such as: https://home.sandiego.edu/~ekim/e194rfs01/jwmatcher/matcher2.html), but when port 1 is matched, the second one is not (and takes pointless values - e.g. s11 has -30dB which is ok, but then s22 = +17dB).

The amplifier and mentioned circuits are designed in AWR Microwave Environment and s2p file of the LNA is attached to this post. I'm working according to following procedure:
1. Check input impedance of amplifier (both real and imagine part)
2. Use matching calculator to design input circuit - enter value of impedance from point no. 1, center frequency 24GHz, and 50ohm standard for simple LC circuit
3. Check output impedance of amplifier with consideration of input matching circuit
4. Design output matching circuit by using calculator

What I'm doing wrong ?
Regards,
E.

View attachment LNA.zip

If S22 is greater than one, the amplifier is not stable..

if im right, the mistake you are doing is not change the device impedance into complex conjugate.

there are two ways you can match the device:
1) match from the device impedance (input/output) to 50ohm.
2) match from 50ohm to the device impedance (input/output).

for 1) you can use the actual device impedance. for 2) you have to match from 50ohm to complex conjugate impedance of the device.