Annular ring patch antennas

A study of the concentric annular ring is reported in which the rings are excited in different modes at the same or different frequencies to provide a variety of satellite services to a vehicle. For example future cars and trucks will have access to mobile satellite telecommunications systems and satellite positioning systems. Compact antennas will be required, mounted inconspicuously onto the roof, to receive these services together with traffic information data. Not only are these services likely to be operated at different frequencies but the radiation pattern requirements will also be different