Optimized coding scheme for class-S amplifiers

Author

Wentzel, Andreas ; Meliani, Chafik ; Heinrich, Wolfgang

Author_Institution

Ferdinand-Braun-Inst. (FBH), Berlin, Germany

fYear

2011

fDate

10-13 Oct. 2011

Firstpage

329

Lastpage

332

Abstract

This paper is based on a voltage-mode class-S power amplifier for the 450 MHz band using GaN-MMICs. To optimize back-off performance, the conventional topology is modified and the circuit is operated using different coding schemes for the input signal. While for the classical band-pass delta-sigma modulation, a peak output power of 2.3 W with 38% drain efficiency is obtained, tests using a pulse-width modulation approach yield significant improvements, with a maximum output power of 3 W with more than 80% drain efficiency. At 6 dB and 10 dB power back-off, 60% and 40% efficiency are achieved, respectively.

Keywords

III-V semiconductors; MMIC power amplifiers; UHF power amplifiers; delta-sigma modulation; encoding; gallium compounds; pulse width modulation; wide band gap semiconductors; GaN; GaN-MMIC; bandwidth 450 MHz; class-S power amplifier; classical band-pass delta-sigma modulation; optimized coding scheme; pulse width modulation; voltage-mode power amplifier; Encoding; Microwave amplifiers; Microwave communication; Modulation; Power amplifiers; Switches; GaN; MMIC; Microwave power amplifiers; class-S; delta-sigma modulation; pulse-width modulation; switch-mode;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Conference (EuMC), 2011 41st European

Conference_Location

Manchester

Print_ISBN

978-1-61284-235-6

Type

conf

Filename

6101745