Impact of S22 on the FoM of an Rf Power Amplifier

Hi,

How does the S22 of a device impact the figures of merit of the rf power amplifier? I would guess O/P matching networks, but I'd appreciate some details. Additionally, I have a kink in my measured S22, how would it impact the performance of my amplifier? Thanks.

It depends on the power and type of your PA.As well known, High Power Amplifiers are designed in according with Load Pull Technique so S22 of this type of amplifier will be less effective.