Amplificador de Potencia Doherty de 25 W, 70% de Eficiencia y Back Off de Salida de 6 dB para Aplicaciones a 2,4 GHz, con Control de VGS, PEAK

This paper shows the design and simulation results of a hybrid Doherty power amplifier. The amplifier has been designed at 2,4 GHz, obtaining power-added efficiency above 70 % for 6 dB output power back-off, together with a small signal gain of 17 dB. Design and analysis equations are presented considering class AB bias conditions for the main amplifier and class C for the peak one in back-off larger than 6 dB, and FET device assumption. An additional control on the bias point of the peak device has been carried out, in order to increase the gain on the Doherty region and ease the design of the peak branch. A Cree’s GaN-HEMT CGH40010F device has been used with a nonlinear model guarantied up to 6 GHz and with an expected output power of 10 W. The obtained output power is higher than 25-W. The simulation has been carried out using Agilent ADS CAD tools. The present design could present the state of the art in terms of continuous-wave (CW) characterizationEste artículo muestra el diseño y los resultados de simulación de un amplificador de potencia Doherty sobre tecnología híbrida. El amplificador fue diseñado a 2,4 GHz, obteniendo una eficiencia de potencia aditiva arriba del 70 % a 6-dB debajo de saturación, junto con una ganancia a pequeña señal de 17 dB. Las ecuaciones de análisis y diseño son presentadas considerando polarización clase AB para el amplificador principal y clase C para el amplificador auxiliar a 6-dB debajo de saturación, y dispositivos FET. Un control adicional sobre el punto de polarización del dispositivo auxiliar se ha llevado a cabo, para incrementar la ganancia en la región Doherty y facilitar el diseño de la rama auxiliar. Un dispositivo GaN-HEMT CGH40010 de Cree ha sido usado con un modelo no-lineal garantizado hasta 6-GHz y con una potencia de salida esperada de 10-W. La potencia de salida obtenida es mayor a 25-W. La simulación ha sido llevada a cabo usando Agilent ADS. El presente diseño representaría el estado del arte en términos de caracterización de onda continua (OC)

A 0.6–3.8 GHz GaN Power Amplifier Designed Through a Simple Strategy

This letter presents the design strategy for an ultrawideband, high-efficiency hybrid power amplifier based on a commercial GaN-HEMT. The measurement results demonstrate a state-of-the-art fractional bandwidth of 145.5%, with saturated output power higher than 10 W from 0.6 to 3.8 GHz and power added efficiency exceeding 46% in the whole band, thus covering most of the mobile frequencies and making this device suitable for small-base station applications. The simple design approach exploits a N-section transformer, and allows for a priori estimation of the bandwidth: in the proposed case, a good agreement between estimated and measured bandwidth is obtaine

El amplificador de potencia Doherty con etapa de pre-amplificación

This paper shows the general concept of the Doherty power amplifier, highlighting its superiority, in terms of average efficiency, regarding to single-stage power amplifiers. Furthermore, the posibility of including preamplification stages, in both branches of the Doherty power amplifier is presented, with the goal of increasing its gain.Este artículo presenta el concepto general del amplificador de potencia Doherty, resaltando su superioridad, en términos de eficiencia promedio, con respecto a amplificadores de una etapa. Además, se presenta la posibilidad de incluir etapas de pre-amplificación en las ramas del amplificador Doherty, con el objetivo de incrementar su ganancia

The Doherty Power Amplifier: Design strategy

This paper shows a proposal of methodology for designing Doherty Power Amplifiers (DPAs) with arbitrary output-back-off (OBO), main and peak devices. As a demonstration, a 7.5dB OBO DPA has been designed, using two devices from Cree Inc, and simulated in Advanced Design System 2014. The amplifier uses the GaN-HEMT CGH40006 and CGH40010 devices, for main and peak branches, respectively. On the Doherty region, an output power of 25.1W has been obtained together with a gain higher than 15dB, whereas the obtained added efficiency has been demonstrated to be between 57 and 63%

Amplificador de Potencia Doherty de 25 W, 70% de Eficiencia y Back Off de Salida de 6 dB para Aplicaciones a 2,4 GHz, con Control de VGS, PEAK.

Este artículo muestra el diseño y los resultados de simulación de un amplificador de potencia Doherty sobre tecnología híbrida. El amplificador fue diseñado a 2,4 GHz, obteniendo una eficiencia de potencia aditiva arriba del 70 % a 6-dB debajo de saturación, junto con una ganancia a pequeña señal de 17 dB. Las ecuaciones de análisis y diseño son presentadas considerando polarización clase AB para el amplificador principal y clase C para el amplificador auxiliar a 6-dB debajo de saturación, y dispositivos FET. Un control adicional sobre el punto de polarización del dispositivo auxiliar se ha llevado a cabo, para incrementar la ganancia en la región Doherty y facilitar el diseño de la rama auxiliar. Un dispositivo GaN-HEMT CGH40010 de Cree ha sido usado con un modelo no-lineal garantizado hasta 6-GHz y con una potencia de salida esperada de 10-W. La potencia de salida obtenida es mayor a 25-W. La simulación ha sido llevada a cabo usando Agilent ADS. El presente diseño representaría el estado del arte en términosde caracterización de onda continua (OC)

Wideband Doherty Power Amplifier: A Design Approach

This paper presents a simple method to design wideband Doherty power amplifiers (DPAs) based on the synthesis of a combiner network which can mimic the response of an ideal compensation of the device reactive output equivalent network and exploit the maximum power capabilities of the device. Using the Wolfspeed’s CGH40006 and CG2H40025 GaN HEMT devices, two DPAs were designed and simulated to demonstrate the effectiveness of the proposed approach. In both cases, a 1.4 GHz bandwidth was obtained together with an efficiency higher than 44 and 49% at 6 dB OBO. The saturated output power was higher than 41.2 and 47 dBm over the band, for the DPAs using the CGH40006 and CG2H40025 devices, respectively

Ecuaciones cerradas para el diseño de amplificadores clase F

This paper shows a methodology for designing class F amplifiers based on closed equations that allow the direct calculation of the output matching network. For the sake of proving, a prototype has been carried out using the Cree´s device GaN HEMT CGH40010, obtaining a maximum drain efficiency of 65 %, small signal gain of 14.2 dB and saturated output power of 41 dBm, using sinusoidal excitation. The drain voltage and current waveforms are coherent with theory and the results in continuous-wave are outstanding.Este artículo muestra una metodología para el diseño de amplificadores clase F, basada en ecuaciones cerradas que permiten el cálculo directo de la red de acople de salida. Como demostración, un prototipo ha sido realizado usando el dispositivo GaN HEMT CGH40010 de Cree, obteniendo una eficiencia de drenaje máxima de 65%, ganancia a pequeña señal de 14.2 dB y potencia de salida en saturación de 41 dBm, usando excitación tipo sinusoidal. Las formas de onda obtenidas para el voltaje y la corriente de drenaje son coherentes con la teoría y los resultados en onda-continua son sobresalientes

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

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 line 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