Load-Modulated GaN Power Amplifier Implementing Tunable Thick Film BST Components

M.T. Arnous1, A. Wiens2, S. Preis1, H. Maune2, K. Bathich1, M. Nikfalazar2, R. Jakoby2 and G. Boeck1,3

Published in:

Proc. 43th European Microwave Conf. (EuMC 2013), Nuremberg, Germany, Oct. 7-10, pp. 1387-1390 (2013).

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In this work, a novel adaptive broadband power amplifier (PA) design based on barium-strontium-titanate (BST) components for dynamic load modulation (DLM) is presented. The designed PA, driven in class C, makes use of a commercial GaN HEMT, and is intended to operate over 1.8-2.2 GHz with maximum output power of 43 dBm together with high efficiency at maximum output power level. At back-off output power operation, the tunable BST-based output matching network introduces the optimum load impedance for high efficiency. The frequency and input power dependent impedance tunability is realized using a Π-structure matching topology based on thick film BST varactors which have a very high breakdown voltage of higher than 500 V.

1 Microwave Engineering Laboratory, Berlin Institute of Technology Berlin, Germany
2 Institute for Microwave Engineering and Photonics Technische Universitaet Darmstadt Darmstadt, Germany
3 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin, Germany


Adaptive matching; broadband; BST; dynamic load; efficiency enhancement; ferroelectrics, GaN HEMT; load modulation; power amplifer; tunable component.