Filtering Push–Pull Power Amplifier Based on Multifunctional Impedance Matching Network

Abstract

A filtering push–pull power amplifier (PPPA) is presented based on the multifunctional impedance matching network (MIMN), which is constructed by coupled lines and open-circuited transmission lines. Due to the symmetry of designed MIMN, the even-and odd-mode method is employed to analyze the operating mechanisms, which reveal that designed MIMN can achieve high common mode suppression under the even-mode excitation, while provide good impedance transformation and filtering response under the odd-mode excitation. Finally, a filtering PPPA based on the MIMN is designed as well as measured, and the measured operating frequencies are ranging from 1.85 to 2.03 GHz. The measured maximum gain and peak power-added efficiency are 13.9 dB and 57.8%, while the measured upper stopband extends to 4.1f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> with the suppression level of 20 dB.