Microwave amplifier Design

by plotting s parameter and transforming the impedance @ 1.3 GHz to 50 ohm (if 50 ohm terminated system)... better use ADS !

the output impedance of the transistor at the center frequency (fo) is Zo, the impedance at the @2fo is zero, and infinite at @3fo. Class F amplifier technique is a way of manipulating the harmonics in order to boost the efficiency. I recommend you this book:

http://www.amazon.com/Efficiency-Mic.../dp/0470513004

Using s-parameters is useless in designing "switch mode amplifiers" because they are not valid anymore in this mode.
E-class or F-class amplifiers are desgined by using nonlinear models and HB simulation technique.
Grebennikov's "High Efficiency Power Amplifer Design" book will help you and some other papers of IEEE on this subject.