Measurement technique for increasing the linearity by optimising the source: impedance of RF power amplifiers

Author

Vuolevi, Joel ; Rahkonen, Timo ; Manninen, Jani

Author_Institution

Dept. of Electr. Eng., Oulu Univ., Finland

fYear

2000

fDate

2000

Firstpage

227

Lastpage

230

Abstract

Out-of-band source impedances have a significant impact on the linearity of RF power stages. The source-pull measurement technique presented in this paper shows that linearity improvements up to 8 dB for a CE BJT stage can be achieved by providing optimum source impedance at the envelope frequency. If predistorters are used, the memory effects caused by the stage and predistorter can be partially cancelled by providing optimum source impedances at different envelope frequencies. As a result, the cancellation performance of the predistorter will be significantly improved

Keywords

electric impedance measurement; impedance matching; intermodulation distortion; power amplifiers; power bipolar transistors; CE BJT stage; IM3 distortion; RF power amplifiers; active load principle; envelope frequency; linearity improvement; optimum source impedance; out-of-band source impedances; partially cancelled memory effects; predistorter cancellation performance; source-pull measurement technique; Distortion; Impedance; Integrated circuit modeling; Linearity; Measurement techniques; Power amplifiers; Radio frequency; Transconductance; Vectors; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Radio and Wireless Conference, 2000. RAWCON 2000. 2000 IEEE

Conference_Location

Denver, CO

Print_ISBN

0-7803-6267-5

Type

conf

DOI

10.1109/RAWCON.2000.881896

Filename

881896