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Impact evaluation of DC operating condition on DPD linearizability and power efficiency in GaN-based power amplifiers

Published online by Cambridge University Press:  29 May 2019

Konrad Jędrzejewski*
Affiliation:
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
Dawid W. Rosołowski
Affiliation:
Warsaw University of Technology, Institute of Radioelectronics and Multimedia Technology, Warsaw, Poland
Wojciech Wojtasiak
Affiliation:
Warsaw University of Technology, Institute of Radioelectronics and Multimedia Technology, Warsaw, Poland
*
Author for correspondence: Konrad Jędrzejewski, E-mail: konrad.jedrzejewski@pw.edu.pl

Abstract

The paper presents the results of studies on the effect of transistor DC operating conditions on GaN power amplifiers’ (PAs) power efficiency and linearity improved by digital predistortion (DPD). The single-ended 10 W (ISM2.45 GHz) and 150 W (3.4/3.6 GHz) GaN HEMT PAs excited by wideband LTE20 E-TM1.1 signal were tested. To check the applicability of the small-signal approach for designing of LTE signals’ PAs, the 150 W PA using transistor model extracted from S-parameters measured at the properly selected operating points was designed. The conventional DPD based on the indirect learning architecture and the memory polynomial model of PA non-linearity was implemented. The results of the research show that in case of class A and B PAs operating up to several dozen watts, an additional improvement in adjacent channel leakage ratio (ACLR) of the order of a few dB only by an increase in the quiescent drain current of PA transistor can be achieved. However, a noticeable ACLR improvement with a coincident increase in power-added efficiency (PAE) can be obtained by choosing the compromise DC operating point and using DPD. In the case of high-PAs, the linearity and efficiency are strongly dependent on the load of a transistor, thus the role of DPD is significantly increased.

Type
MIKON 2018
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2019 

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References

1.Raab, FH (2001) Class-E, class-C, and class-F power amplifiers based upon a finite number of harmonics. IEEE Transactions on Microwave Theory and Techniques 8, 14621468.Google Scholar
2.Doherty, WH (1936) A new high efficiency power amplifier for modulated waves. Proceedings of the Institute of Radio Engineers 24, 11631182.Google Scholar
3.Cripps, SC (2002) Advanced Techniques in RF Power Amplifier Design. Norwood, US: Artech House.Google Scholar
4.Kahn, LR (1952) Single-sideband transmission by envelope elimination and restoration. Proceedings of the IRE 7, 803806.Google Scholar
5.Hassan, M, Kwak, M, Leung, VW, Hsia, C, Yan, JJ, Kimball, DF and Asbeck, PM (2011) High efficiency envelope tracking power amplifier with very low quiescent power for 20 MHz LTE. IEEE Radio Frequency Integrated Circuits Symposium, pp. 14.Google Scholar
6.Chireix, H (1935) High power outphasing modulation. Proceedings of the Institute of Radio Engineers 23, 13701392.Google Scholar
7.Katz, A, Wood, J and Chokola, D (2016) The evolution of PA linearization: from classic feedforward and feedback through analog and digital predistortion. IEEE Microwave Magazine 2, 3240.Google Scholar
8.Ghannouchi, FM, Oualid, H and Helaoui, M. (2015) Behavioral Modeling and Predistortion of Wideband Wireless Transmitters. Norwood, US: John Wiley & Sons.Google Scholar
9.Wood, J (2014) Behavioral Modeling and Linearization of RF Power Amplifiers. Norwood, US: Artech House.Google Scholar
10.Cripps, SC (2006) RF Power Amplifiers for Wireless Communications. Norwood, US: Artech House, Inc.Google Scholar
11.Walker, J (1993) High-Power GaAs FET Amplifiers. Norwood, US: Artech House, Inc.Google Scholar
12.Wojtasiak, W and Gryglewski, D (2011) A 100 W SiC MESFET amplifier for L-band T/R module of APAR. International Journal of Electronics and Telecommunications 57, 135140.Google Scholar
13.Wojtasiak, W, Gryglewski, D and Sędek, E (2002) 100 W class A power amplifier for L-band T/R module. Journal of Telecommunications and Information Technology 1, 1113.Google Scholar
14.Cree (2015) CGH27015 15 W, 28 V, GaN HEMT for Linear Communications ranging from VHF to 3 GHz, datasheet.Google Scholar
15.NXP (2016) A2G35S200-01SR3, RF Power GaN Transistor, datasheet.Google Scholar
16.Eun, CH and Powers, EJ (1997) A new Volterra predistorter based on the indirect learning architecture. IEEE Transactions on Signal Processing 1, 223227.Google Scholar
17.Ding, L, Zhou, GT, Morgan, DR, Ma, Z, Kenney, JS, Kim, J and Giardina, CR (2002) Memory polynomial predistorter based on the indirect learning architecture. Proc. of IEEE Global Telecommunications Conference GLOBECOM ‘02, Taiwan, pp. 967971.Google Scholar
18.Kim, J and Konstantinou, K (2001) Digital predistortion of wideband signals based on power amplifier models with memory. Electronics Letters 23, 14171418.Google Scholar
19.Schetzen, M (1980) The Volterra and Wiener Theories of Nonlinear Systems. Norwood, US: Wiley.Google Scholar
20.ETSI TS 136 141 LTE; Evolved Universal Terrestrial Radio Access (E-UTRA); Base Station (BS) conformance testing (3GPP TS 36.141 version 10.12.0 Release 10), Sect. 6.Google Scholar
21.Analog Device (2017) AD9371/AD9375 System Development User Guide UG-992.Google Scholar