CGH27060F

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 Son – Ildu Kim – Junghwan Moon – Juyeon Lee – Bummam Kim – An asymmetric Doherty Power Amplifier (ADPA) is introduced using a new output combining circuit for easy of implementation with a large matching tolerance. The proposed APDA has been implemented using GaN HEMT devices at 2.6 GHz for WiMAX signal with 5MHz bandwidth and 8.3 dB peak to average power ratio.

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 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 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 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.