Abstract: Electromagnetic engineers and scientists normally work in the frequency domain. We take advantage of the principle of superposition to break down problems into small, manageable, harmonic components, thus greatly simplifying the analysis of an electromagnetic system. This talk examines what happens when we consider electromagnetics from the time domain, looking at instantaneous instead of time-averaged behavior. This talk further considers what happens when the effects superposition allows us to ignore are added back in to our electromagnetic worldview. The resulting perspective leads to some surprising and counterintuitive conclusions. For instance:
- The source of radiation energy is not necessarily localized with accelerating charges.
- "Near" fields may be present in free space, even arbitrarily far away from sources or scatterers.
- Radio waves, or at least their associated energy, can "bounce" and interact with each other, even in free space.
This perspective has already been of value in making precise indoor location systems and may help lead to more robust antenna designs in the presence of multipath.
Bio: Hans G. Schantz is CTO of The Q-Track Corporation, and a co-inventor of NFER® technology. His prior work experience includes stints with IBM, the Lawrence Livermore National Lab, The ElectroScience Lab of the Ohio State University, and Time Domain Corporation. Author of The Art and Science of Ultra-wideband Antennas (Artech House, 2005), his forty U.S. patents include antennas, RF systems, RF-based location systems, and related inventions. He is a Senior Member of the IEEE, a member of the Institute of Navigation, and an amateur radio operator KC5VLD. Schantz earned his Ph.D. in physics from the University of Texas at Austin in 1995. He also holds degrees in Industrial Engineering and Physics from Purdue University. Dr. Schantz blogs at ĘtherCzar and is @ĘtherCzar on Twitter.