A class-J power amplifier with varactor-based dynamic load modulation across a large bandwidth
Paper in proceedings, 2015

A novel class-J operated power amplifier (PA) utilizing varactor-based dynamic load modulation is presented. It is theoretically shown that the proposed PA can maintain high average efficiency across more than 35% RF bandwidth by means of a purely reactive load modulation after the transistor output capacitance. The theory is experimentally verified by a 15 W GaN HEMT PA operating from 1.80 to 2.20 GHz, using SiC varactors as dynamically tunable load elements. In the band, the PA presents a power added efficiency (PAE) higher than 39% at 6 dB output power back-off. For a 3.84 MHz W-CDMA signal with 6.7 dB peak to average power ratio, an average PAE higher than 39% and an adjacent channel leakage ratio below -45.8 dBc are obtained across the entire band after linearization.

power amplifiers

wideband

Energy efficiency

silicon carbide (SiC)

varactors

gallium nitride (GaN)

Author

William Hallberg

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

David Gustafsson

Ericsson AB

MUSTAFA ÖZEN

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Christer Andersson

Mitsubishi Electric Corporation

Dan Kuylenstierna

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Christian Fager

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

2015 IEEE MTT-S International Microwave Symposium, IMS 2015

7166734

Areas of Advance

Information and Communication Technology

Subject Categories

Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1109/MWSYM.2015.7166734

ISBN

978-1-4799-8275-2

More information

Latest update

11/19/2018