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EMI (Electromagnetic Interference) is one of the major concerns today in the automotive industry. The main reason is that vehicles are using and depending more on electronic technology. The causes of electromagnetic interference problems are not only related to the ever-increasing number of embedded electronics systems in vehicles, but also to external electronic devices that are brought in to automobiles by drivers and passengers (e.g. cell phone, MP3 players, Bluetooth devices, portable video games). Even though these problems can cause serious issues on safety systems like the airbag, their symptoms are often noticed in a less harm way in the sound system. A very common EMI problem in automotive sound systems is a particular noise caused by devices that uses GSM (Global System for Mobile Communications) technology. Most of the cell phones and vehicle locators rely on GSM technology.

This work presents a methodology for carrying out open site tests of VHF-FM vehicular systems. The approach here developed characterizes antennas, coaxial cables and RF amplifiers performance in terms of normalized experiments. The efficiency of the procedure adopted is also proven.

The finite element method (FEM) can be used as an analysis tool in automotive electromagnetic engineering and recently new technologies such as Domain Decomposition Method (DDM) were employed to simulate very large field structures such as a whole vehicle. A FEM solver offers numerous advantages over other numerical methods, such as method of moments (MoM) and finite difference time domain (FDTD), because it has the ability to handle complex heterogeneous and anisotropic materials which is often used inside vehicles, also providing a very precise representation of complex geometries via high order tetrahedral elements. Nevertheless, for large field problems such as the scenario of the ISO 11451-2 where an antenna radiates a vehicle in an anechoic chamber, FEM solvers requires an interface between an infinite domain to a finite domain through the use of radiating boundary conditions on artificial truncation surfaces. This causes the solver to model a great quantity of air regio.

Since the majority of the innovative trends in automotive industry today are based in advanced electronics technology, mastering the EMI (Electromagnetic Interference) between embedded electronic subsystem and the EMC (Electromagnetic Compatibility) features of a vehicle in its early design phase becomes one of the crucial technical challenges faced by all automotive manufacturers. Even if all electronic subsystems in a vehicle are validated under the EMC standards, the integration between them may create numerous points of potential hazards that affects the total electromagnetic behavior of the entire system, hazards that can be detected only once the first complete prototype is available, and whose resolution at this phase of the process is very time consuming and expensive.