Dr. Benoit Derat
Dr. Benoit Derat
Dr. Derat received the engineering degree from SUPELEC in 2002 and a Ph.D. degree in physics from University of Paris XI with honors in 2006. From 2002 to 2008, he worked at SAGEM Mobiles as an antenna design and electromagnetics research engineer. In 2009, he founded ART-Fi, which created the first vector-array Specific Absorption Rate measurement system. Dr. Derat operated as the CEO and President of ART-Fi, before joining Rohde & Schwarz in Munich in 2017. He is now working as Senior Director for Systems Developments and Project Implementations, covering Electromagnetic Compatibility, Over-The-Air, and antenna test applications. Dr. Derat is a Senior Member of the Antenna Measurement Techniques Association (AMTA) and the author of more than eighty scientific conference and journal papers, as well as an inventor on more than forty patents, with the main focus in antenna systems near- and far-field characterization techniques.
Talk 1: How Close Can Far-Field Be? Getting the Best Out of Your Measurement Range
Trends in modern wireless communications, including the use of massive MIMO and millimeter wave frequencies, have supported an increased deployment of electrically large antennas. This created technical and economic challenges as many EMC or regulatory tests require a far-field condition. This talk provides an overview of the recent findings in defining the shortest possible far-field test distance, depending on the size of the device under test, its operation frequency, the target metric and the upper bound acceptable measurement deviation. Practical ways are also described to determine the maximum antenna aperture size that can be tested in the far-field at a given frequency and for a maximum error, in an existing chamber with a defined range length.
Talk 2: The Antenna Digital Twin – When Measurements and Simulations Unite
Antenna or OTA measurements are blind. Knowing the detailed implementation of the device under test is not needed to realize them. They even include all production tolerances that might impact performance. However, measurements are limited to canonical test environments, e.g. in anechoic chambers. Simulations, on the contrary, can give access to electromagnetic fields in practically any scenario. Yet, simulations are only as good as the knowledge of the very details of the radiation source. What if one could unite the two and benefit from the combined strengths of experimental and numerical techniques? This talk shows how to enable this with the augmented OTA approach, involving the creation of an antenna digital twin, based on actual measured data. Practical applications are demonstrated, including field characterization inside the car and EMF assessments with virtual human models.
Talk 3: Performing OTA Measurements in an EMC Range – A Real or False Good Idea?
Getting the money and space for implementing more anechoic chambers serving various test purposes can be a difficult path. The question “Dear Test & Measurement Solution Supplier, I have a large full-vehicle EMC chamber. Could you modify it, so it can do both EMC and OTA measurements?” is increasingly asked these days. Even though the evaluation of unintended electromagnetic radiation phenomena and intended radiation performance have a lot in common, they also differ in many respects. This talk discusses the trade-off that has to be made when choosing to combine EMC and OTA in one test environment and discusses the scope of specific combinations that work better than others.