Array antenna principle applied to modern car antennas for mobile communication

For most types of car antennas the car body acts as a functional part of the antenna. By use of several antenna elements or structures and by application of the array antenna principle, under incorporation of the radiation properties of the car body, the antenna characteristics can then be changed or influenced specifically, i.e. this method has been applied to mobile phone array antennas with short elements to achieve an almost omnidirectional radiation pattern or on FM-diversity backlite antenna systems to improve the diversity efficiency.