Absorbed Power Density Assessment Using Simulation-Augmented Over-the-Air Measurement

Abstract

This paper proposes a novel approach for fast human exposure absorbed power density assessment, based on a combination of over-the-air radiative field measurements and full-wave electromagnetic simulations. This so-called augmented OTA technique relies on the computation of an equivalent source or digital twin, which reproduces the radiation properties of the device under test. At short separation distances, the interaction between the human model and the device is however not negligible. A novel solution to model the influence of multiple reflections is introduced, where the inside of the equivalent source box is partially filled with a perfect electric conductor, thereby creating a reflective digital twin model. Simulation and measurement results demonstrate the relevance of this technique for enabling accurate absorbed power density evaluations. A discussion on aspects influencing the measurement time and uncertainty is also provided, where a new demonstration is delivered how spatial-averaging contributes positively to the accuracy of the method.

Keywords

• RF exposure
• antenna measurements
• over-the-air testing
• numerical modeling