Ultra-Wideband Power Amplifier Design Strategy for 5G Sub-6-GHz Applications

Abstract

This paper presents a strategy to design ultrawideband power amplifiers with a fractional bandwidth of approximately 200%. It exploits a simple output matching network, which consists of a series transmission lines together with a shunt stub, to compensate the output parasitic network of the device. Following this, a multisection transformer is implemented to obtain the optimal load at the intrinsic drain plane. As design examples, several output matching networks were designed for two different size GaN HEMT devices. One of these examples was implemented and characterized, and a drain efficiency from 52% to 70% and an output power between 40 dBm and 42.5 dBm were obtained, over 67% of the 5G sub-6-GHz band (i.e., 0.1 to 4 GHz). The aforementioned results, to the best of the authors’ knowledge, represent the state of the art in broadband power amplifiers.

A Differential Combiner for Quasi-Complete Cancellation of Output Capacitance in mm-Wave Power Amplifiers With High-$Q$ Devices

“…1 illustrates a new proposal along with its equivalent circuit. In this representation, the transistor outputs, assumed here for convenience as Field-Effect Transistor (FET), function as current generators, while their parasitic output effects are encapsulated in first approximation by the equivalent capacitance denoted as C OUT [15]- [18]. For the sake of simplicity in the subsequent analysis, both devices are presumed to be identical and operating within the linear region.…”