Contact MTT-11 Webmaster
Nuno Borges Carvalho
Last Updated 04-08-2008

Distinguished Microwave Lecturer

Paul Tasker

Paul Tasker is an MTT-S Distinguished Microwave Lectrurer, DML, starting 2008.

The Title of his talk is Engineering and Measuring RF Waveforms

 Abstract — the unifying link between system performance, circuit design and transistor technology This talk discusses how appropriately engineered RF waveforms can help meet telecommunication system goals such as power, efficiency, and linearity. It is well known that the performance of transistors in power amplifiers is linked to their mode of operation (Class A, A/B, C, etc.). A number of measurement systems now allow for the direct measurement of RF waveforms, either at RF or in the envelope domain. Coupling such systems with impedance control hardware enables experimental control (engineering) of these terminal RF waveforms. Because these measurement systems operate in the time domain they allow for a more natural integration of measurement and CAD simulation based design approaches. This talk touches on several topics of interest to microwave engineers including modeling and measurement of power amplifier transistors and circuits; design and predistortion correction of nonlinear telecommunication systems; and circuit design methods that incorporate new transistor technology. Examples will demonstrate measurement feedback to support and link both the design of high power amplifier transistor technology (GaAs HBT/HFET, GaN HFET, Si LDMOS) and the circuit environment (harmonic load-pull, linearisation via base-band injection).

For more information about the Distinguished Microwave Lecturer program, click here.

Past DML - Doug Rytting

Doug Rytting, an MTT-S Distinguished Microwave Lecturer, has been a DML till December 2006, with a talk entitled, "Calibration and Error Correction Techniques for Network Analysis,". If you are interested his talk, please contact him by email at rytting@sbcglobal.net.

Doug Rytting has won the 2007 IEEE Joseph F. Keithley Award in Instrumentation & Measurement

Calibration and Error Correction Techniques for Network Analysis

The accuracy of Vector-Network-Analyzer (VNA) measurements depends critically on calibration and error correction techniques. This talk will cover the evolution of conventional VNA calibration methods from the start of network analysis through the development of new calibration methods for waveform and large-signal analysis. Included will be the original SOLT (Short-Open-Load-Through) methods, the newer self-calibration techniques like TRL, LRL and Unknown-Thru, and the strengths and weaknesses of these various VNA calibration approaches. The talk will conclude with a discussion of new state-of-the-art extensions of the traditional VNA calibration strategy for calibrated waveform measurements at microwave frequencies capable of capturing the both the temporal and large-signal behavior of microwave and digital devices.