Highly Efficient Broadband Continuous Inverse Class-F Power Amplifier Design Using Modified Elliptic Low-Pass Filtering Matching Network

A multistage second harmonic control output matching network is proposed in this article. Through the fundamental and harmonic impedance matching at multiple frequencies in the target band, the accuracy of the fundamental and harmonic impedance of the continuous power amplifier is improved. The efficiency is improved consequently. A highly efficient broadband continuous inverse Class‐F power amplifier based on this structure is designed and fabricated using a CGH40010F GaN HEMT packaged device. The measurement results demonstrate that drain efficiency of 71% to 82% and output power of 40.1 to 41.5 dBm is achieved with more than 10 dB gain across 1.35 to 2.35 GHz.

Section: Design Philosophymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Highly efficient broadband continuous inverse Class‐F power amplifier using multistage second harmonic control output matching network

Wang

Cheng

et al. 2020

“…Consequently, to design extended continuous Class‐B/J PA better, this transistor nonlinear model CGH40010F provided by Cree is used. Meanwhile, the simplified model used for simulation, extracted from datasheet and from the transistor model provided by manufacturer, is shown in Figure . The simplified nonlinear model consists of two elements: drain equivalent current source and parasitic component equivalent model.…”

Section: Design Of Multioctave Bandwidth Extended Continuous Class‐b/mentioning

confidence: 99%

Design of multioctave high‐efficiency power amplifier based on extended continuous Class‐B/J modes

Xuan

Yang

Liu

2019

The bandwidth covered by contemporary communication technologies has reached over an octave. But most existing power amplifier (PA) configurations cannot meet this requirement while at the same time maintaining a high efficiency. Therefore, a novel structure for bandwidth enhancement at a high efficiency level is proposed together with the systematic design methodology in this article. The difficulty lies in the overlap of the fundamental and harmonic frequencies. On this issue, the extended continuous Class‐B/J mode can extend the impedance of the second harmonic to a resistive‐reactive and relax design requirements for overlapping design space of fundamental and second harmonic frequencies. Specifically, the presented innovative circuit structure uses the multiple frequencies matching method to manipulate four fundamental and the corresponding second harmonics frequency points simultaneously, which can further effectively expand the bandwidth on the basis of the extended continuous Class‐B/J PA. To verify the validity of the proposed theory, a gallium nitride multioctave PA is designed, implemented, and measured. Measured results show a fractional bandwidth of 148.4% from 0.4 to 2.7 GHz, with drain efficiency of 63%‐78%, saturated output power greater than 39 dBm, and large signal gain larger than 9 dB. For the single carrier WCDMA signal with a channel bandwidth of 3.84 MHz and a peak to average power ratio of 6 dB, the adjacent channel power ratio of −47.5 to −35 dBc and −42.8 to −31.5 dBc at an average output power of 33 and 36 dBm separately are achieved over the whole frequency band.

“…The linearity of conventional overdriven inverse Class‐F PA is studied, and good linearization results are achieved by adopting the digital pre‐distortion (DPD) technique. Compared with the conventional transmitter, the DLM transmitter can enhance the efficiency performance at the cost of moderate degradation in linearity .…”

Section: An Example Of Lm Inverse Class‐f Pasmentioning

confidence: 99%

Investigation of load modulated inverse Class-F power amplifier with extended conduction angle

You

Helaoui

et al. 2018

A novel design space of load modulated (LM) inverse Class‐F power amplifiers (PAs) with extended conduction angle is proposed. The effects of the driven level factor β and the biasing operation factor ρ on the third‐harmonic generation are discussed. The harmonic generation mechanism shows that the knee voltage effects are the source of third‐harmonics for LM inverse Class‐F PAs. The definition of the inverse Class‐F mode is consistently valid under the circumstance of load modulation in a limited output power back‐off (OPBO) range. Meanwhile, the conduction angle θ0 can be extended from π/2 to a limited value (<110°) to keep the standard waveforms of inverse Class‐F mode and maintain high efficiency. After introducing the “continuous concept” and the second harmonic manipulation method, the mathematical design space of inverse Class‐F PAs with extended conduction angle is derived. Calculation shows that the purely conductive load modulation can enable high back‐off efficiency operation for LM inverse Class‐F PAs. As proof of concept, a demonstrator amplifier is fabricated and measured. The experimental results show that the power added efficiency (PAE) with optimum Vctrl is improved by 5% over an OPBO range of 6 dB compared with the same PA with fixed Vctrl.