A combined transmit/receive feed system for personal mobile communications in l/s-band in consideration of increased power applications

A strong increase in the demand for regional GEO based mobile communication services is expected during the next decade. Since the GEO systems operate in L- or S-band, they require reflectors with diameters typically ranging between 12 and 15 m and a corresponding feed system of more than 100 radiating elements. With respect to accommodation and mass one combined transmit / receive (Tx/Rx) antenna is preferred rather than two separate transmit and receive antennas. Another advantage of the combined antenna is the congruence between up- and downlink beams considering the narrow footprints of the beams (typical: 0.6° to 0.8°), this is an important issue.