Title :
Inverted-load network for high-power Doherty amplifier
Author :
Kwon, Sungwook ; Kim, Minsu ; Jung, Sungchan ; Jeong, Jonghyuk ; Lim, Kyunghoon ; Van, Juho ; Cho, Hanjin ; Kim, HyungChul ; Nah, Wansoo ; Yang, Youngoo
Author_Institution :
Sungkyunkwan Univ., Suwon
fDate :
2/1/2009 12:00:00 AM
Abstract :
In this article, a high-power, high-efficiency inverted Doherty power amplifier (PA), having a more compact load network than that of the conventional Doherty amplifier, was designed and implemented for wide-band code-division multiple access (WCDMA) base-station applications. Its configuration and working principle are compared with the conventional Doherty amplifier. For experimental verification, we implemented an inverted Doherty amplifier, using a 190 W peak-envelope-power (PEP) laterally diffused metal-oxide-semiconductor (LDMOS) field-effect transistors (FETs). Using a four-carrier down-link WCDMA signal, we achieved a high power-added efficiency (PAE) of 32% and an average output power level as high as 46.3 dBm at a given adjacent channel leakage ratio (ACLR) level of -30 dBc. This is a 9.5% improvement in efficiency and 1 dB improvement in output power under the same ACLR conditions from those of the balanced class-AB operation using the same devices.
Keywords :
MOSFET; code division multiple access; wideband amplifiers; LDMOSFET; adjacent channel leakage ratio level; average output power level; field-effect transistors; four-carrier down-link WCDMA signal; high-power Doherty amplifier; inverted-load network; laterally diffused metal-oxide-semiconductor; power-added efficiency; wide-band code-division multiple access base-station applications; Broadband amplifiers; Circuits; FETs; High power amplifiers; Impedance; Linearity; Multiaccess communication; Peak to average power ratio; Power amplifiers; Power generation;
Journal_Title :
Microwave Magazine, IEEE
DOI :
10.1109/MMM.2008.930680
