Title :
Enhanced Class-A/AB mobile terminal power amplifier efficiency by input envelope injection and “self” envelope tracking
Author :
Kheirkhahi, Alireza ; Asbeck, Peter M. ; Larson, Lawrence E.
Author_Institution :
Dept. of Comput. & Electr. Eng., Univ. of California, San Diego, La Jolla, CA, USA
Abstract :
A baseband modulation technique is proposed to improve the efficiency and linearity of Class-A/AB radio frequency (RF) power amplifiers (PAs). The baseband load impedance is optimized, and the input envelope - along with the RF signal - is fed to the PA input. The resulting baseband modulation of the drain increases the saturated RF output power and improves the linearity for a given dc power consumption. A 2GHz HFET power amplifier exhibited a significant improvement in peak PAE from 40% to 54% for a two-tone input and from 23% to 27% for a 5MHz BW 64-QAM signal.
Keywords :
UHF power amplifiers; high electron mobility transistors; BW 64-QAM signal; Class-A-AB radiofrequency power amplifiers; DC power consumption; HFET power amplifier; RF output power; baseband modulation technique; enhanced Class-A-AB mobile terminal power amplifier efficiency; frequency 2 GHz; frequency 5 MHz; input envelope injection; self envelope tracking; Baseband; Linearity; Logic gates; Modulation; Power amplifiers; Power generation; Radio frequency; Class A/AB power amplifier; efficiency improvement; envelope injection; envelope termination; self envelope tracking;
Conference_Titel :
Microwave Symposium Digest (MTT), 2011 IEEE MTT-S International
Conference_Location :
Baltimore, MD
Print_ISBN :
978-1-61284-754-2
Electronic_ISBN :
0149-645X
DOI :
10.1109/MWSYM.2011.5972901
