Title :
Analysis of a class E power amplifier with series-parallel resonator
Author :
You, Fei ; He, Shunfan ; Tang, Xiaoou ; Cao, Tian
Author_Institution :
Sch. of Electron. Eng., Univ. of Electron. Sci. & Technol. of China, Chengdu
fDate :
12/1/2008 12:00:00 AM
Abstract :
The authors propose new class E power amplifier configuration with an equivalent series-parallel resonator network. The boundary conditions for the 100% efficiency operations are analysed under the conditions that the duty ratio is 0.5 and the loaded quality factor is infinite. If the DC supply voltage and the output power are assumed the same, the load resistance R is 53.65% higher, the excess series inductance L x is 3.99% lower and the maximum frequency f max is improved by 6.47% compared with the conventional class E amplifier. The theoretical analysis is verified by numerical results and harmonic balance simulations. And a lumped element test board is built and measured at 200%MHz utilising a lateral double diffused metal oxide semiconductor (LDMOS) transistor MRF21010 as the switching device. An output power of 33.03%dBm, a drain efficiency of 85.6% and a gain of 16%dB are measured. The approximate transmission-line topology with harmonics suppression is also proposed.
Keywords :
Q-factor; power amplifiers; resonators; transistors; DC supply voltage; LDMOS; MRF21010; class E power amplifier; drain efficiency; efficiency operations; equivalent series-parallel resonator network; excess series inductance; frequency 200 MHz; harmonic balance simulations; harmonics suppression; lateral double diffused metal oxide semiconductor transistor; load resistance; loaded quality factor; lumped element test board; output power; switching device; transmission-line topology;
Journal_Title :
Circuits, Devices & Systems, IET
DOI :
10.1049/iet-cds:20080096