Title: Signal Derivative Sampling in Electromagnetic Field Measurements
Speaker: Dr. Olav Breinbjerg; AMTA Distinguished Speaker; ElMaReCo
Date: May 8, 2025
Time: 11:00 am – 12 pm US Eastern Time
The sampling of a signal derivative, in addition to the signal itself, allows the number of sampling points to be reduced to half – and the sampling step thus to be increased to twice – that of the standard Nyquist-Whittaker-Shannon-Kotelnikov-Someya sampling theorem. This derivative sampling theorem – holding the potential of reducing measurement time – is exact and general; it applies to measurements and signal processing at large, it does not imply under-sampling or compressed sensing, and it does not rely on a priori information. We first derive and discuss analytic closed-form expressions for both the Fourier spectrum and the interpolation formula for periodic as well as and non-periodic bandlimited signals. Next, we investigate the performance of the derivative sampling theorem through numerical modelling based on experimental full-circle and full-sphere C-band antenna measurements – including the effect of measurement noise and the consequential uncertainty. Finally, we study basic designs of derivative probes based on probe-fed square waveguides for the TE10, the TE20, and the HEM11 waveguide modes – taking inspiration from mono-pulse antenna technology. The derivative sampling theorem may find wide usage in e.g. holography, imaging, microscopy, remote sensing, scanning, scattering, and testing of antennas and materials.
Olav Breinbjerg received the M.Sc. and Ph.D. degrees in electrical engineering from the Technical University of Denmark (DTU) in 1987 and 1992, respectively. He was on the Faculty of DTU’s Department of Electrical Engineering as Assistant Professor from 1991 to 1995, Associate Professor from 1995 to 2005, and Full Professor from 2006 to 2021. From 1997 to 2021 he was also Head of the Electromagnetic Systems Group and the DTU-ESA Spherical Near-Field Antenna Test Facility, and he founded the DTU Electromagnetic Test Centre. He resigned his position at DTU in 2021 and founded ElMaReCo for independent research consultancy. Olav Breinbjerg was a Visiting Scientist at Rome Laboratory in 1988, a Fulbright Research Scholar at the University of Texas at Austin in 1995, and a Visiting Professor at the University of Siena in 2011 and 2022. His research is generally in applied electromagnetics - and particularly in antennas, antenna measurements, computational techniques, and scattering - for applications in wireless communication and sensing technologies. He is the author or co-author of more than 75 journal papers, 250 conference papers, and 250 technical reports. Dr. Breinbjerg was a recipient of a U.S. Fulbright Research Award in 1995, the 2001 AEG Elektron Foundation's Award, the 2003 DTU Student Union's Teacher of the Year Award, the 2013 and 2015 European School of Antennas Teacher of the Year Awards, the 2020 Hans Christian Ørsted Award, and the 2023 AMTA Distinguished Achievement Award. Dr. Breinbjerg is Fellow of AMTA, Fellow of IEEE, Knight of the Order of Dannebrog, and the 2024-2025 AMTA Distinguished Speaker.
About AMTA Webinar Series:
The AMTA webinar series was introduced to highlight latest antenna measurement technologies to the AMTA community. Speakers are selected from the best papers presented at the AMTA conferences.
Members - You can watch the recordings of the previous webinars here.
