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Drain‐voltage dependency of memory effects in W‐CDMA base station digital predistortion linearizers with compound semiconductor power amplifiers
Author(s) -
Takano Takeshi,
Oishi Yasuyuki,
Maniwa Toru,
Hayashi Hiroyuki,
Kikkawa Toshihide,
Araki Kiyomichi
Publication year - 2005
Publication title -
microwave and optical technology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.304
H-Index - 76
eISSN - 1098-2760
pISSN - 0895-2477
DOI - 10.1002/mop.20876
Subject(s) - predistortion , amplifier , high electron mobility transistor , linearizer , electrical engineering , voltage , engineering , adjacent channel , high voltage , electronic engineering , optoelectronics , materials science , transistor , cmos
With regard to wideband predistortion type power amplifiers, such as shared amplifiers used in W‐CDMA base stations, the memory effects associated with RF power amplifiers degrade power efficiency. Aiming to solve this problem, we find that a high‐voltage compound semiconductor device has sufficient ACLR performance to mitigate these memory effects. We tested two kinds of compound‐semiconductor devices, namely, a GaAs FET and a GaN HEMT. The GaAs FET, with an operating voltage (V op ) of 12 V, a saturation output of 240 W, and a push–pull configuration, was used as a low‐voltage device. The GaN HEMT, with V op of 50 V, a saturation output of 200 W, and a push–pull configuration as well, was used as a high‐voltage device. The test results for these devices in a predistortion linearizer configuration show that the high‐voltage device (the GaN HEMT) achieved excellent characteristics in terms of distortion suppression and drain efficiency in four‐carrier W‐CDMA applications. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 551–554, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20876