CGH40090

by Raymond S. Pengelly – William Pribble – Thomas Smith

This Simulation of power amplifiers (PAs) for modern wireless base station and small cell systems is an essential part of the design process. At a cell site – the PA consumes the bulk of the dc power – generates the most heat – and thus represents the greatest operational cost. Maximum PA efficiency is a necessity to manage these costs – which is a sizeable challenge in a PA that also must be highly linear to support the complex multilevel modulation types and wide bandwidths used for current and developing wireless transmission standards. Accurate simulation allows the PA designer to meet these challenges by exploring the available design options and then optimizing the circuit that is selected for the application.

by Junghwan Moon – Young Yun Woo – Bummam Kim

A novel design of the Doherty power amplifier (PA) to improve the efficiency at a back-off output power level.

by David Yu-Ting Wu and Slim Boumaiza

A new Doherty amplifier configuration with an intrinsically broadband characteristic is presented based on the synthesis of key ideas derived from the analyses of the load modulation concept and the conventional Doherty amplifier. Important building blocks to implement the proposed Doherty amplifier structure are outlined – which include the quasi-lumped quarter-wave transmission line – as well as the Klopfenstein taper for broadband impedance matching.

by Jangheon Kim – Junghwan Moon – Jungjoon Kim – Slim Boumaiza – and Bumman Kim – A novel design method without requiring the special harmonic termination circuit for a highly efficient power amplifier (PA) is proposed.

by Raymond S. Pengelly – Simon M. Wood – James W. Milligan – Scott T. Sheppard – and William L. Pribble

by Bumman Kim – Ildu Kim – Junghwan Moon

This article describes the design of a GaN Doherty power amplifier with digital pre-distortion as well as hybrid envelop elimination and restoration / envelop tracking technique (H-EER/ET).

by Raymond S. Pengelly – Brad Millon – Donald Farrell – Bill Pribble – and Simon Wood

Presentation from the 2008 IEEE MTT-S International Microwave Symposium (IMS) Workshop on Challenges in Model-Based HPA DesignThis presentation discusses attributes of GaN HEMTs – Wolfspeed GaN HEMT models – design examples (Broadband CW Amplifiers and Linear WiMAX Amplifier) – and future model improvements.

by David Yu-Ting Wu – Farouk Mkadem – Slim Boumaiza – Abstract

A comprehensive approach for designing broadband and highly efficient power amplifier based on optimal impedance analysis and simplified real frequency technique SRFT) is presented.

by Junghwan Moon – Jangheon Kim – Jungjoon Kim – Ildu Kim – Bummam Kim

This paper presents an approach to mitigating the knee voltage effect of the Doherty power amplifier (PA) – especially on the carrier amplifier.

by Jangheon Kim: Farouk Mkadem; Slim Boumaiza

This paper proposes a new broadband saturated power amplifier (SPA) with a distributed second harmonic termination supporting multi-band/multi-mode operation. Due to the multiple harmonic terminations – the proposed PA improves the frequency range where the PA can achieve a high efficiency.

by Sebastian Preis; Daniel Gruner; Georg Boeck

The class-B/J mode continuum in power amplifiers (PAs) defined at the current source plane is discussed considering different parasitic elements including C DS as well as the package. Based on this realistic device description the change of the continuous load impedances depending on the reference plane is demonstrated. It is shown that the design flexibility predicted by the continuous mode theory decreases if the transistor package is taken into account. The presented investigations provide the basis for the design of a broadband GaN PA.

by Donald A. Gajewski – Scott Sheppard – Simon Wood – Jeff B. Barner – Jim Milligan – and John Palmour.

This paper discusses the reliability performance of Wolfspeed GaN/AlGaN high electron mobility transistor (HEMT) MMIC released process technologies – fabricated on 100 mm high purity semi-insulating (HPSI) 4H-SiC substrates.

by Donald A. Gajewski – Scott Sheppard – Tina McNulty – Jeff B. Barner – Jim Milligan and John Palmour

This paper reports the reliability performance of the Wolfspeed – GaN/AlGaN HEMT MMIC process technology – fabricated on 100 mm high purity semi-insulating (HPSI) 4H-SiC substrates.

by Ivan Boshnakov – Anna Wood – Simon Taylor

In the world of RF and microwave engineering – the design and development of solid-state amplifiers is a specialty. It has always required many years of specialized engineering experience and a suitable collection of test and measurement equipment. While these will always be necessary – to be successful in the marketplace today – it is also essential to use a combination of specialized and general CAD tools.

by Ivan Boshnakov; Anna Wood; Simon Taylor

In the world of RF and microwave engineering – the design and development of solid-state amplifiers is a specialty. It has always required many years of specialized engineering experience and a suitable collection of test and measurement equipment. While these will always be necessary – to be successful in the marketplace today – it is also essential to use a combination of specialized and general CAD tools.

by Ildu Kim – Jangheon Kim – Junghwan Moon – Jungjoon Kim – and Bumman Kim

Demonstrating a highly efficient Hybrid Envelope Elimination and Restoration transmitter for IEEE 802.16e Mobile WiMAX applications using a highly efficient saturated Power Amplifier (PA). For the optimum H-EER operation – the PA has been designed to have a maximum PAE at the average Vds region by using 10 W (P3dB ) GaN High Electron Mobility Transistor.

by Khaled Bathic; Georg Boeck

This paper presents the design of a wideband harmonically-tuned Doherty amplifier. The frequency-dependent back-off efficiency degradation was minimized by compensating the effect of the frequency-sensitive impedance inverters over the design band. Suitable choice of device size ratio as well as harmonic load tuning at back-off and maximum power operations were also considered – resulting in superior performance over the targeted design band.