Optimum Satellite Home Receiving Antenna Size at C Band

The crowding of the orbital arc with the attendant imposition by the FCC of the 20 orbital spacing requirements between satellites will end the trend toward smaller satellite home receiving antennas. Smaller antennas (less than 10 feet in diameter), which are subject to interference from adjacent satellites, will be replaced by larger antennas. In this paper the expected interference is calculated, and the resulting received signal-to-noise ratio is estimated. To ensure interference-free C band´ reception under the present 20°, spacing requirement, the results indicate that the receiving antenna diameter should not be smaller than about 11 feet. In high satellite EIRP cases, only by increasing the antenna size to 16 feet or larger is it possible to achieve improvement over an 11 foot antenna. For sizes between 11 and 16 feet, performance degrades in comparison with an 11 foot antenna because the interference falls onto the antenna´s side lobes and is not sufficiently attenuated.