Compact circular polarized antenna for mobile reception of radio signals transmitted by geostationary satellites

Mobile usage of satellite services requires special antennas for optimum exploit of the available link margin. Especially for radio services transmitting via geostationary satellites, an antenna with optimum shaped radiation pattern and circular polarized field is presented. The antenna consists of two parts, a horizontal structure for horizontal polarization and a vertical structure for vertical polarization. The combination of the two parts allows for optimized power ratio and phasing and therefore variable axial ratio. This is useful e.g. with respect to a polarization diversity application with 4 antennas. Antenna characteristics are investigated by simulations and measurement. To ensure the performance of the antenna in real applications the characteristics are investigated on different chassis.