Title :
Transfer characteristic of IM3 relative phase for a GaAs FET amplifier
Author :
Suematsu, Noriharu ; Iyama, Yoshitada ; Ishida, Osami
Author_Institution :
Inf. Technol. R&D Center, Mitsubishi Electr. Corp., Kanagawa, Japan
fDate :
12/1/1997 12:00:00 AM
Abstract :
The transfer characteristic of relative phase of the third-order intermodulation distortion (IM3) of a GaAs FET amplifier is measured and analyzed. The measurement system and method are also described. For drives in the weakly nonlinear region, the measured relative phase of IM3 is equal to that of the carrier and is in agreement with the analysis results using Volterra-series representation. For drives in the saturation region, the measured relative phase of IM3 versus the input power moves drastically compared with that of the carrier and is in agreement with numerical analysis using discrete Fourier transform. Comparison between measured and analytical results shows the drastic move of IM3 relative phase is caused by the generation of IM3 due to AM-PM conversion. The measured results and the measurement method are useful for the design and adjustment of predistortion-type linearizers for GaAs FET high-power amplifiers
Keywords :
III-V semiconductors; MESFET circuits; Volterra series; discrete Fourier transforms; gallium arsenide; intermodulation distortion; microwave amplifiers; AM-PM conversion; GaAs; IM3 relative phase; Volterra-series representation; discrete Fourier transform; high-power amplifiers; microwave FET amplifier; predistortion-type linearizers; saturation region; third-order intermodulation distortion; transfer characteristic; weakly nonlinear region; Discrete Fourier transforms; Distortion measurement; Drives; FETs; Gallium arsenide; High power amplifiers; Intermodulation distortion; Numerical analysis; Phase measurement; Power measurement;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
