2026 AMTA Webinar: Overview & Application of the Generalized Vector Theorem (Oct. 1)
Title: Overview & Application of the Generalized Vector Theorem
Speaker: Dr. Marc Dirix, Albatros Project Belgium
Date: October 1, 2026
Time: 11:00 am – 12 pm US Eastern Time
The generalised vector addition theorem is perhaps one of the least well understood but most commonly utilised mathematical methods found within the field of modern antenna range measurements. Addition theorems such as Graf’s find particular application within the pre-processing of probe data within the pattern compensation portion of many standard near-field to far-field transforms with their utility being largely limited to this one narrow area. In general, addition theorems provide formulas for the expansion of one field representation in terms of another, thereby providing a connection between alternative expressions of the same field referenced to different coordinate systems. This webinar will illustrate that with care, the different adaptations may be used to perform different tasks, including for their use in probe correction, as well as for performing generalised antenna position translations. These translations may be performed rigorously, in any direction, by amounts that may be electrically small or large, and where the fields may include both propagating and reactive, i.e. evanescent, components.
This webinar will therefore present a summary of the relevant standard spherical theory before progressing to highlighting the differences between the various addition formulas. The presentation will also illustrate their various uses across a range of commonly encountered antenna measurement tasks including standard transformations, range assessments, phase centre determination, frequency domain reflection suppression, etc. thereby attempting to shed much needed light on this important, but hitherto veiled topic.
Dr.-Ing. Marc Dirix received the Dr.-Ing. in information and communication technology from the RWTH Aachen University, Germany in 2018. Previously, he had his master’s degrees in information and communication technology by the same University in 2009. During 2004 to 2015, he worked as a researcher and teacher at the Institute of High Frequency Technology of the RWTH Aachen University, Germany, where his main research topics were antenna measurements and material characterisation. In 2004, he has founded the Marc Dirix /RF company which focuses on material measurement automation for RF applications.
From 2017, Marc Dirix has then worked with Antenna Systems Solutions on the development and implementation of antenna measurement systems ranging from micro- to mm-wave for the commercial and research markets, including near-field and compact range systems. Since 2025 he joined E&C Anechoic Chambers, Westerlo, Belgium, where he is responsible for the development of RF measurement and chamber simulations. During 2025 he also returned as a visiting researcher at the Institute of High Frequency Technology of the RWTH Aachen University, Germany. Dr.-Ing. Dirix has developed special experience with near-field antenna measurements, compact antenna test range design, performance prediction and installation, design of antennas for measurement applications and machine learning, and has published numerous peer-reviewed papers on these topics. In 2025 he was a best technical paper awardee at the Antenna Measurement Techniques Association annual meeting and symposium in Tucson, Arizona. He is a Senior Member of both the Antenna Measurement Techniques Association and the IEEE.
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.
