Design approach towards automotive FM broadcast antennas based on characteristic modes

The design of integrated FM broadcast reception antennas for automotive applications is a particularly challenging task since the operational wavelength is of the order of geometrical dimensions of the vehicle. This causes standing wave effects and adversely affects the resulting radiation pattern. On the other hand, the increasing number of car platforms and decreasing time-to-market cycles necessitate a systematic and potentially car platform-independent design approach. This paper demonstrates how the characteristic mode analysis can be used to develop antenna structures integrated into the rear screen of the car in a systematic manner. The simulation results are compared to measurement results and show promising agreement.