N. Wolff, W. Heinrich, O. Bengtsson
12th German Microwave Conference (GeMiC 2019), Stuttgart, Germany, Mar. 25-27, ISBN 978-3-9812668-9-4, pp. 131-134 (2019).
Class-G supply modulation, i.e., discrete level supply modulation, is a powerful efficiency enhancement technique. It allows wideband modulated operation of RF power amplifiers and high output power. For massive multiple-input multiple-output functionality in 5G systems, phased array antennas can be used to implement dynamic beamforming, similar to radar systems. Different configurations for driving the phased array antennas are possible. The configuration under investigation consists of a single baseband source that is distributed to antennas driven by dedicated power amplifiers with controllable input delay lines. This complexity-reduced topology where the power amplifiers are discretely supply modulated with the same supply waveform has only minor impact on the efficiency improvement. Instead the linearityis limited by a trade-off that depends on the relative modulation bandwidth, the electrical antenna size and the beam angle. It is shown that planar phased array antennas with 2×2 or 4×4 elements can be efficiently driven with this topology and an efficiency improvement of 10%-points can be achieved. Even 8×8 phased arrays are supported by this topology at reduced bandwidth and beam angles.
Ferdinand-Braun-Institut, Leibniz-Insitut für Höchstfrequenztechnik, Berlin, Germany
class-G, supply modulation, RF power amplifiers, MIMO, phased array.
Copyright © 2019 IEEE - All rights reserved and © IMA e.V. Ratingen, Germany. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE and IMA.
Full version in pdf-format.