High-Efficiency Harmonic-Peaking Class-EF Power Amplifiers with Enhanced Maximum Operating Frequency


Autoria(s): Thian, Mury; Barakat, Ayman; Fusco, Vincent
Data(s)

01/02/2015

Resumo

The recently introduced Class-EF power amplifier (PA) has a peak switch voltage lower than that of the Class-E PA. However, the value of the transistor output capacitance at high frequencies is typically larger than the required Class-EF optimum shunt capacitance. Consequently, soft-switching operation that minimizes power dissipation during off-to-on transition cannot be achieved at high frequencies. Two new Class-EF PA variants with transmission-line load networks, namely, third-harmonic-peaking (THP) and fifth-harmonic-peaking (FHP) Class-EF PAs are proposed in this paper. These permit operation at higher frequencies at no expense to other PA figures of merit. Analytical expressions are derived in order to obtain circuit component values, which satisfy the required Class-EF impedances at fundamental frequency, all even harmonics, and the first few odd harmonics as well as simultaneously providing impedance matching to a 50- Ω load. Furthermore, a novel open-circuit and shorted stub arrangement, which has substantial practical benefits, is proposed to replace the normal quarter-wave line connected at the transistor's drain. Using GaN HEMTs, two PA prototypes were built. Measured peak drain efficiency of 91% and output power of 39.5 dBm were obtained at 2.22 GHz for the THP Class-EF PA. The FHP Class-EF PA delivered output power of 41.9 dBm with 85% drain efficiency at 1.52 GHz.

Formato

application/pdf

Identificador

http://pure.qub.ac.uk/portal/en/publications/highefficiency-harmonicpeaking-classef-power-amplifiers-with-enhanced-maximum-operating-frequency(5183c8ad-15e6-4f51-afe5-11e717ea4c73).html

http://dx.doi.org/10.1109/TMTT.2014.2386327

http://pure.qub.ac.uk/ws/files/13486996/author_postprint.pdf

Idioma(s)

eng

Direitos

info:eu-repo/semantics/openAccess

Fonte

Thian , M , Barakat , A & Fusco , V 2015 , ' High-Efficiency Harmonic-Peaking Class-EF Power Amplifiers with Enhanced Maximum Operating Frequency ' IEEE Transactions on Microwave Theory and Techniques , vol 63 , no. 2 , pp. 659-671 . DOI: 10.1109/TMTT.2014.2386327

Tipo

article