Conference Paper

"Hybrid" Approach to microwave power amplifier design

Dept. of Eng., Univ. di Ferrara, Ferrara, Italy
DOI: 10.1109/INMMIC.2010.5480145 Conference: Integrated Nonlinear Microwave and Millimeter-Wave Circuits (INMMIC), 2010 Workshop on
Source: IEEE Xplore


A new “hybrid” approach to microwave power amplifier design is presented which is based both on experimental large-signal low-frequency I/V load-line characterization and a model-based description of the device capacitances. Such a technique allows to get the same information obtained through nonlinear measurement setups operating at microwave frequencies. Several simulated and experimental data are proposed, based on GaN technology, in order to prove the effectiveness of the methodology.

4 Reads
  • Source
    • "Nevertheless, conventional PA design techniques rely on external driving sources and loads to iteratively optimize the internal waveforms. On the contrary, Raffo et al. started the PA design process from the intrinsic reference plane and embedded the nonlinear or linear parasitic components on top of the intrinsic load lines, to predict the input impedance and necessary harmonic loads at the extrinsic reference planes (ERPs) [7], [15]. This technique has been successfully applied to the design of class-E [16] and class-F [17], [18] amplifiers. "
    [Show abstract] [Hide abstract]
    ABSTRACT: A fully model-based nonlinear embedding device model including low- and high-frequency dispersion effects is implemented for the Angelov device model and successfully demonstrated for load modulation power-amplifier (PA) applications. Using this nonlinear embedding device model, any desired PA mode of operation at the current source plane can be projected to the external reference planes to synthesize the required multi-harmonic source and load terminations. A 2-D identification of the intrinsic PA operation modes is performed first at the current source reference planes. For intrinsic modes defined without lossy parasitics, most of the required source impedance terminations will exhibit a substantial negative resistance after projection to the external reference planes. These terminations can then be implemented by active harmonic injection at the input. It is verified experimentally for a 15-W GaN HEMT class-AB mode that, using the second harmonic injection synthesized by the embedding device model at the input, yields an improved drain efficiency of up to 5% in agreement with the simulation. A figure-of-merit is also introduced to evaluate the efficacy of the nonlinear embedding PA design methodology in achieving the targeted intrinsic mode operation given the model accuracy.
    IEEE Transactions on Microwave Theory and Techniques 09/2014; 62(9):1986-2002. DOI:10.1109/TMTT.2014.2333498 · 2.24 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: An innovative, recently introduced, methodology for microwave power amplifier design, is here extended to switching- mode Class-E amplifier operation. Such a technique is based on a complete and accurate electron device (ED) characterization, which is provided by both direct large-signal low-frequency I/V measurements, performed by means of a relatively simple low- cost setup, and a model-based description of nonlinear reactive effects related to ED capacitances. In order to verify the proposed design methodology, a Class-E power amplifier (PA) has been designed. Keywords-Design methodology; Integrated circuit design; Integrated circuit measurements; Microwave amplifiers; Power amplifiers; Waveform engineering I. INTRODUCTION Switching mode power amplifiers (PAs) are increasingly attracting microwave PA designers due to the excellent performance in terms of efficiency. Moreover, designers interest was surely encouraged by recent GaN technology that, due to the high breakdown voltage of GaN transistors, allows to overcome output power limitations related to switching classes of operation (e.g., Class-E (1)), that are mainly imposed by the maximum drain voltage achievable under nonlinear dynamic operation.
  • [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents an intrinsic high efficiency Class-F power amplifier with a commercial packaged transistor (CGH55015F from Cree). A recently proposed “hybrid” approach for PA design is adopted with modification. The current generator characteristic is extracted from low frequency simulation. The designed power amplifier achieves 79.2% power added efficiency (PAE) at 1 GHz with 40.3 dBm output power.
    Integrated Nonlinear Microwave and Millimetre-Wave Circuits (INMMIC), 2012 Workshop on; 01/2012
Show more

Similar Publications