The influence of vehicle hull on a radiated emission

This paper contributes to an issue related to prediction of potential electromagnetic compatibility problems in a vehicle design process. This work begins a series of articles describing the method of assessment and prediction of electromagnetic radiation of complex, large scale, electrical objects, such as electric cars. This paper examines the influence of a vehicle hulls on an electromagnetic radiation excited by an electrical device located inside it. For this purpose, a simplified model of vehicle electronics is taken. A set of electronic devices and their enclosures can be considered as an unintentional source of electromagnetic field. The impact of hull is analyzed from this point of view. The statistic estimation gives an account of how the hull changes the field strength, and what is the new direction of the main field pattern lobe. Typical resonant frequencies of the hull and Q-factor are considered, as well as various positions inside the car where the electronics can cause potential electromagnetic compatibility problems. Although the estimation is not absolutely precise, the simplified model gives a comprehensive assessment of the electronics emission. The goal is to find out whether the car hull and electronics inside can be still considered as an unintentional emitter, to compare the radiation characteristics with the unintentional emitter model and to know limitations of this approach. Results obtained from the analysis are used in a methodology aimed at prediction of the system-level emission on the basis of component-level emission measurements. However, they can be used in making rapid measurement and radiation prediction methods, which are required at a design and vehicle prototyping stage, etc. in software like rule-checking or expert systems.