Title :
Ultra-linear distributed class-AB LDMOS RF power amplifier for base stations
Author :
van der Heijden, M.P. ; de Graaff, H.C. ; de Vreede, L.C.N. ; Gajadharsing, J.R. ; Burghartz, J.N.
Author_Institution :
Lab. of ECTM, Delft Univ. of Technol., Netherlands
Abstract :
This paper describes a distributed amplifier, employing multiple parallel-connected LDMOS devices with optimized overall transconductance for class-AB operation. In comparison to a conventional amplifier under class-A and class-AB conditions the design method results in a significant linearity improvement over a large dynamic range. Measurements demonstrate a linearity improvement of 20 dB in 3/sup rd/-order intermodulation distortion (IM3) and 10 dB in adjacent channel power ratio (ACPR) for a wideband CDMA signal. Consequently, a reduction in the required back-off level has been achieved.
Keywords :
MOSFET circuits; code division multiple access; distributed amplifiers; intermodulation distortion; power amplifiers; radiofrequency amplifiers; adjacent channel power ratio; back-off level; base station; class AB operation; distributed LDMOS RF power amplifier; dynamic range; intermodulation distortion; linearity; transconductance; wideband CDMA signal; Broadband amplifiers; Design methodology; Distortion measurement; Distributed amplifiers; Dynamic range; Linearity; Power amplifiers; Radio frequency; Radiofrequency amplifiers; Transconductance;
Conference_Titel :
Microwave Symposium Digest, 2001 IEEE MTT-S International
Conference_Location :
Phoenix, AZ, USA
Print_ISBN :
0-7803-6538-0
DOI :
10.1109/MWSYM.2001.967149
