Inexpensive Microwave Antenna Demonstrations Based on the IEEE Presentation by John Kraus

Author: Jon Wallace

Abstract: After seeing a video of John Kraus giving a demonstration on radio antennas to the IEEE many years ago, the author was so inspired that he researched the concepts and sought to reproduce as much of the demonstration as he could. It is hoped that these demonstrations will educate and inspire others to explore as well. They cover topics which include: beam width, inverse square law, polarization, reflection, refraction, interference, absorption, gain, wave guides, diffraction, and more. The equipment used consists of a Gunn diode source with horn antenna and a WR-90 horn antenna with crystal detector, instrumentation amplifier, and voltage controlled oscillator (VCO) so that changes in intensity will be heard as pitch changes.

Episode 1: Introduction, Thanks, Equipment, Safety, Near/Far Field, Beamwidth, Gain, Inverse Square Law, and Linear Polarization

Episode 2: Reflection, Refraction, Waveguides and Circular Polarization

Episode 3: Ground Plane, Parabolic Dish, Other Antennas – Helical; Log-Periodic; Vivaldi; Dipole w/Reflector/Director; Loop; Square; J-pole; Bent Rod Ground Plane

Episode 4: Diffraction – 2 Slit, Knife Edge Fresnel Lens/Antenna

The original article in PDF format