CG2H80015D

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 Ellie Cijvat – Kevin Tom – Mike Faulkner – and Henrik Sjöland – This paper describes the design – simulation and measurement of a GaN power amplifier suitable for envelope and phase signal combination.

by William L. Pribble – Jim M Milligan – and Raymond S. Pengelly – Abstract from the 2006 IEEE Topical Workshop on PAs for Wireless Communications (RWS) Presentation from the 2006 IEEE Radio and Wireless Symposium in San Diego A class-E power amplifier based on a GaN HEMT cell has been designed and tested.

by William L. Pribble – Jim M Milligan – and Raymond S. Pengelly – Abstract from the 2006 IEEE Topical Workshop on PAs for Wireless Communications (RWS) Presentation from the 2006 IEEE Radio and Wireless Symposium in San Diego A class-E power amplifier based on a GaN HEMT cell has been designed and tested.

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

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 Junghwan Moon; Seunghoon Jee; Jungjoon Kim; Jangheon Kim; Bumman Kim – Operational behaviors of the class-F and class-F amplifiers are investigated. For the half-sinusoidal voltage waveform of the class-F amplifier – the amplifier should be operated in the highly saturated region – in which the phase relation between the fundamental and second harmonic currents are out-of-phase. The class-F amplifier can operate at the less saturated region to form a half sinewave current waveform. Therefore – the class-F amplifier has a bifurcated current waveform from the hard saturated operation – but the class-F amplifier operates as a switch at the saturated region for a second harmonic tuned half-sine waveform.

by J. A. García – B. Bedia – R. Merlín – P. Cabral and J. C. Pedro – An experimental procedure is proposed for accurately characterizing the Vdd-to-AM and Vdd-to-PM nonlinearities in a Class E power amplifier (PA). Based on GaN HEMT technology,…

by Neal Tuffy – Anding Zhu – and Thomas J. Brazil – This work outlines a design approach used for achieving highly efficient power amplification over a wide bandwidth – given narrowband passive harmonic load-pull results at a single center frequency.

Paul Saad; Paolo Colantonio; Junghwan Moon; Luca Piazzon; Franco Giannini; Kristoffer Andersson; Bumman Kim; Christian Fager – This paper presents the design – implementation – and experimental results of a highly efficient concurrent dualband GaN-HEMT power amplifier at 1.8 GHz and 2.4 GHz. A bare-die approach – in conjunction with a harmonic sourcepull/load-pull simulation approach – are used in order to design and implement the harmonically tuned dual-band PA. For a continuous wave output power of 42.3 dBm the measured gain is 12 dB in the two frequency bands; while the power added efficiency is 64% in both bands. Linearized modulated measurements – using concurrently 10MHz LTE and WiMAX signals – show an average PAE of 25% and and adjacent channel leakage ratio of -48 dBc and -47 dBc at 1.8 GHz and 2.4 GHz – respectively.

by Hossein Mashad Nemati – Alan L. Clarke – Steve C. Cripps – Johannes Benedikt – Paul J. Tasker – Christian Fager – Jan Grahn – and Herbert Zirath – In this paper – the efficiency of a GaN HEMT transistor and its intrinsic waveforms are measured at 0.9 GHz and investigated for load- and supply-modulation applications.

by Junghwan Moon; Jungjoon Kim; Bumman Kim – This paper presents the operation principle of Class-J power amplifiers (PAs) with linear and nonlinear output capacitors (Cout s). The efficiency of a Class-J amplifier is enhanced by the nonlinear capacitance because of the harmonic generation from the nonlinear Cout – especially the second-harmonic voltage component.

by Mustafa Ozen – Christer M. Andersson – Thomas Eriksson Mustafa Acar – Rik Jos – Christian Fager – This paper studies linearity of a 2 GHz – 10 Watt peak output power RF pulse width modulation (RF-PWM) based transmitter. The transmitter incorporates a tunable load network class-E PA as the final output stage. The tunable load network enables dynamic optimization of the class-E along with the duty cycle resulting in high efficiency over a wide range of output power levels. A digital predistiortion based linearization scheme is proposed to enhance the linearity of the transmitter.

by Paul Saad – Luca Piazzon – Paolo Colantonio – Junghwan Moon – Franco Giannini – Kristoffer Andersson – Bumman Kim – and Christian Fager – This paper presents the design of a high peak efficiency dual-band power amplifier (PA) and how it is adopted as basic cell to implement a high average efficiency Doherty PA (DPA) – achieving a dual-band/multi-mode and efficient transmitter concurrently operating at 1.8 GHz and 2.4 GHz.

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.