Prediction of the maximum electric field level inside a metallic cavity using a quality factor estimation

Abstract

This paper presents a method for predicting the maximum electric field level inside a metallic cavity making use of the quality factor (Q) estimation. This calculation requires a two-step approach combining several theoretical models which can be found in the literature. A very good agreement in the frequency range between 100 MHz and 40 GHz has been achieved with the data obtained from the validation of two reverberation chambers made of different conductive materials. The wide frequency band analyzed permits us to draw conclusions about the main contributions in the cavity Q and their relationships with the maximum electric field level. This paper also describes and identifies the relationships between the antenna parameters and dissipation mechanisms vs. frequency for the different models. This estimation could be used to calculate a possible EMC threat of a spurious emission of EM signals which could produce a susceptibility problem in other equipments installed in the same cavity.

Keywords:

• reverberation chamber
• quality factor
• EMC
• cavities
• electric field estimation
• OCT

Acknowledgement

The authors would like to thank all EMC Department of National Institute for Aerospace Technology personnel for their measurement experience and support in making this study possible. This work has been supported by the Spanish “Ministerio de Economía y Competitividad“ (MINECO) through the project UAVEMI (TEC2013-48414-C3-2-R).