Title :
Increased efficiency in QAM power amplifiers
Author :
Conn, D.R. ; Hemmers, R.N.
Author_Institution :
Dept. of Electr. & Comput. Eng., McMaster Univ., Hamilton, Ont., Canada
Abstract :
A dynamic biasing procedure designed to improve the average dc-rf conversion efficiency of power amplifiers employing multi-level modulation schemes such as QAM is investigated. In this technique, the gate bias voltage is adjusted in accordance with the phasor currently being transmitted. Simulations show promising results for a 1 W class-A mode power amplifier. A system to address the distortion issue and dynamic bias control is proposed.
Keywords :
power amplifiers; quadrature amplitude modulation; radiofrequency amplifiers; 1 W; DC-RF conversion efficiency; QAM; class A power amplifier; distortion; dynamic bias control; multi-level modulation; phasor; simulation; Constellation diagram; Control systems; Multiaccess communication; Power amplifiers; Power generation; Power supplies; Quadrature amplitude modulation; Radiofrequency amplifiers; Time division multiple access; Voltage;
Conference_Titel :
Microwave Symposium Digest, 1998 IEEE MTT-S International
Conference_Location :
Baltimore, MD, USA
Print_ISBN :
0-7803-4471-5
DOI :
10.1109/MWSYM.1998.700694
