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IEEE Transactions on Microwave Theory and Techniques
Volume 48 Number 12, December 2000

Table of Contents for this issue

Complete paper in PDF format

High-Power Time-Domain Measurement System with Active Harmonic Load-Pull for High-Efficiency Base-Station Amplifier Design

Johannes Benedikt, Roberto Gaddi, Paul J. Tasker and Martin Goss

Page 2617.

Abstract:

A measurement system combining vector corrected waveform measurements with active harmonic load-pull extends, for the first time, real-time experimental waveform engineering up to the 30-W power level. The vector correction procedure is presented in this paper. A novel harmonic load-pull approach based on the real-time measurement capability of the system is demonstrated on a 4-W LDMOS device. A 20% increase in maximum output power to 4.7 W without degrading gain and efficiency is realized. Waveform analysis at various drive and load conditions directly identifies nonlinear capacitance effects being a key design issue for the design of highly efficient power amplifier.

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