Series-Combined Coaxial Dielectric Resonator Class-F Power Amplifier System

A high-efficiency class- F power amplifier loading network based on a coaxial dielectric resonator is presented. Low loss and high dielectric constant are among the compelling characteristics that make a dielectric resonator an excellent candidate to realize high-efficiency amplifiers output networks in a circuit area significantly smaller than its microstrip equivalent. In order to achieve 82- W output power with 82 % efficiency, four class-F amplifiers are series-combined using a simple and novel synthesis technique. The results are verified with a UHF prototype at 500-MHz fundamental-frequency based upon GaN FETs. The four-amplifier system is in a 4×6 in area.