On the evening of March 30th, the members and guests of the IEEE Chicago and Rockford Consultants’ Network convened for a lecture called “R F Mixers” presented by Gary Kaatz. Signals processing engineers and microwave system integrators would appreciate the scholarship that Gary Kaatz brings to the problem of characterizing mixer circuit topologies and describing their implementation. Mixers, generally, were presented along a steady progression of component count that started with the Shottkey diode and ended with a MOSFET based “mixer” that encroaches on ideal. The ideal was shown to occur at the intercept point of 2 plots: 1, input port power plot and 2, undesirable distortion power plot, on graph of output power versus input power. The fundamentals of mixers, in general, were not overlooked where it was shown that as input power increases, the output power falls off from ideal. As input power increases, the point where output power deviates from a line by more than 1 decibel has special significance, it was shown.
In addition to expanding the mixer’s transfer equation into higher power levels was ability to apply the mixer in such a manner to avoid interference with other transmission sources, not so linear in practice, so it was presented to networking meeting attendees. While a certain type of non-interference chart would be used less and less in practice by the state of the art in favor computational methods, according to Gary Kaatz, Gary Kaatz was able to show a striking loci to place one’s mixer parameters that deals with interference nicely.
The member meeting was interactive, Gary Kaatz fielding questions and comments from meeting attendees throughout while holding audience interest on his speaking topic. Meeting participants can identify Gary Kaatz’ ability in SDR for cellular, substrate noise handling, LTE power amplifier systems and teaching EET classes. After the presentation was an opportunity to network with Gary Kaatz and to meet with other engineers and consultants interested in growing their careers and professional engineering practices.
References: G. Kaatz, MSEE. Member Lecture, Topic: “R F Mixers”. IEEE Chicago/Rockford Consultants’ Network, Palatine Public Library, Illinois, March 30, 2015.