Broadband class-E Power Amplifier Research Articles

Design, Simulation and Fabrication of Broadband Class-E Power Amplifier Using Double-Reactance Compensation Technique and Second and Third Harmonic Control Circuits

Design, Simulation and Fabrication of Broadband Class-E Power Amplifier Using Double-Reactance Compensation Technique and Second and Third Harmonic Control Circuits

Design of a Highly Efficient Broadband Class-E Power Amplifier with a Low Q Series Resonance

This work presents a method used for designing a broadband class-E power amplifier that combines the two techniques of a nonlinear shunt capacitance and a low quality factor of a series resonator. The nonlinear shunt capacitance theory accurately extracts the value of class-E components. In addition, the quality factor of the series resonator was considered to obtain a wide bandwidth for the power amplifiers. The purpose of using this method was to produce a simple topology and a high efficiency, which are two outstanding features of a class-E power amplifier. The experimental results show that a design was created using from a 130 to 180 MHz frequency with a bandwidth of 32% and a peak measured power added efficiency of 84.8%. This prototype uses an MRF282SR1 MOSFET transistor at a 3-W output power level. Furthermore, a summary of the experimental results compared with other high-efficiency articles is provided to validate the advantages of this method.

Comments on “Design of Highly Efficient Broadband Class-E Power Amplifier Using Synthesized Low-Pass Matching Networks”

In the above paper, the author presents a new methodology for designing and implementing high-efficiency broadband Class-E power amplifiers (PAs) using a high-order low-pass filter-prototype. The designed broadband class-E PA achieves a state-of-the-art performance compared to recently published results. However, an error has been found, which will be clarified in this Letters.

Authors’ Reply to “Comments on ‘Design of Highly Efficient Broadband Class-E Power Amplifier Using Synthesized Low-Pass Matching Networks”’

The authors appreciate the comments made by Cheng et al. [1] that point out an error in [2, eq. (11)] . In [2] , this equation was formed to transform the shunt lumped capacitors into distributed representation with suspended open-ended transmission-lines. As discussed in [1] , the expression of [2, eq. (11)] should be corrected to

Design of Highly Efficient Broadband Class-E Power Amplifier Using Synthesized Low-Pass Matching Networks

A new methodology for designing and implementing high-efficiency broadband Class-E power amplifiers (PAs) using high-order low-pass filter-prototype is proposed in this paper. A GaN transistor is used in this work, which is carefully modeled and characterized to prescribe the optimal output impedance for the broadband Class-E operation. A sixth-order low-pass filter-matching network is designed and implemented for the output matching, which provides optimized fundamental and harmonic impedances within an octave bandwidth ( <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$L$</tex></formula> -band). Simulation and experimental results show that an optimal Class-E PA is realized from 1.2 to 2 GHz (50%) with a measured efficiency of 80%–89%, which is the highest reported today for such a bandwidth. An overall PA bandwidth of 0.9–2.2 GHz (84%) is measured with 10–20-W output power, 10–13-dB gain, and 63%–89% efficiency throughout the band. Furthermore, the Class-E PA is characterized through measurements using constant-envelop global system for mobile communications signals, indicating a favorable adjacent channel power ratio from <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${-}$</tex> </formula> 40 to <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${-}$</tex> </formula> 50 dBc within the entire bandwidth.

Broadband high-efficiency circularly polarized active antenna and array for RF front-end application

This paper presents a broadband high-efficiency circularly polarized (CP) active integrated antenna, and a broadband CP active array at 2 GHz. To realize the broadband CP antenna, a circular patch is aperture coupled by crossed slots in the ground plane, which are fed by an L-shaped microstrip feed line below the ground. The antenna is designed to serve the functions of both a radiator and a harmonics-terminated load for class-E high-efficiency power-amplifier (PA) integration. The broadband CP active antenna is realized by directly integrating the broadband CP antenna with the class-E PA. It achieves a 9% bandwidth (1.84-2.01 GHz) for axial ratio (AR) below 3 dB, and a 12% bandwidth for power-added efficiency (PAE) over 60%. To form the broadband CP active array, four active antenna elements are sequentially rotated, and each element is directly integrated with broadband class-E PA. A low-cost printed-circuit-board technology is employed in fabrication and a pseudomorphic high electron-mobility transistor is used. A peak drain efficiency of 71.5% for the class-E amplifier is measured at 1.95 GHz. The active array achieves a peak-effective radiated power of 39.7 dBm, and PAE is over 50% within a 22.6% bandwidth (1.72-2.16 GHz). The AR is below 3 dB over a 27% bandwidth (1.72-2.26 GHz).

Broadband high-efficiency linearly and circularly polarized active integrated antennas

This paper presents the design, fabrication, and measurements of two broadband high-efficiency active integrated antennas (AIAs) operating in linear polarization and circular polarization, respectively. A new design method is proposed for designing the broadband load network of the class-E power amplifier (PA), so that a high power-added efficiency (PAE) can be achieved over a broad bandwidth. A broadband high-efficiency class-E PA is designed based on the proposed method. The linearly polarized (LP) AIA is realized by integrating the broadband class-E PA with a broadband LP antenna, which uses a ring-slot coupled microstrip patch antenna. Then, the circularly polarized (CP) AIA is realized by integrating the broadband class-E PA with a broadband CP antenna, which uses a single-feed cross-slot-coupled microstrip patch antenna. Each antenna is designed for working as both a radiator and a harmonics-terminated load. A low-cost printed-circuit-board technology is employed in fabrication, and a p-high-electron mobility transistor is used. The PAE of the LP AIA is over 50% within a 14.6% bandwidth from 1.78 to 2.06 GHz, while the PAE of the CP AIA is over 50% within a 14% bandwidth from 1.92 to 2.21 GHz. The axial ratio of the CP AIA is below 3 dB over a 9% bandwidth from 1.99 to 2.18 GHz.

Design of low-cost broadband class-E power amplifier using low-voltage supply

The design of a broadband high-efficiency class-E power amplifier (PA) using a 0.8-μm PHEMT device is presented. In order to achieve broadband operation, a T-transform output-load network is used. Power-added efficiency (PAE) greater than 50% is achieved over a frequency bandwidth of 49%. The simulation and practical results confirm the validity of this approach. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 103–106, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20559