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A C-Band or Ku-Band satellite communication system uses a relatively small receiving antenna while operating within current FCC designated bandwidth and using existing satellite configurations. Aperture synthesis techniques create nulls in orbit locations from which potential interference is expecte

A C-Band or Ku-Band satellite communication system uses a relatively small receiving antenna while operating within current FCC designated bandwidth and using existing satellite configurations. Aperture synthesis techniques create nulls in orbit locations from which potential interference is expected. Bandwidth inefficient modulation techniques reduce transmission power flux density. Video compression reduces the power necessary to transmit video information. These three features make possible a receiving antenna with a receiving area equivalent to that of a three foot diameter dish, at C-Band frequencies. Comparable reductions are possible for Ku-, Ka-, S- and L-Band systems. Compressing the data reduces the required transmitted power by a factor of ten. Spreading the bandwidth reduces the power density below the FCC limitation. However, reducing the antenna diameter increases the beam width of the antenna, hence, the smaller antenna can no longer discriminate between adjacent C-Band satellites in their current orbital configuration. By designing the receiving antenna with nulls in orbital locations where potentially interfering satellites would be located, the small antenna avoids this interference. The same general technique is possible for a Ku-Band Antenna system. The FCC power limits are higher at Ku-Band than C-Band, however, losses due to rain absorption and thermal noise are higher at Ku-Band frequencies. Nevertheless, equivalent size savings on Ku-Band antennas are possible with the combination of the above techniques, when tailored for the Ku-Band environment.

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[ What is claimed is:] [1.] An antenna for receiving a signal being transmitted from a central satellite within a constellation of satellites, in which a plurality of satellites are spaced at predetermined intervals from the central satellite, and for coupling the signal to a receiver, said antenna

[ What is claimed is:] [1.] An antenna for receiving a signal being transmitted from a central satellite within a constellation of satellites, in which a plurality of satellites are spaced at predetermined intervals from the central satellite, and for coupling the signal to a receiver, said antenna comprising:a reflector having an irregularly shaped contour, defined in part by a plurality of areas cut from the reflector, and having a width that defines a main beam of a size that encompasses at least two pairs of satellites in the constellation that are immediately adjacent to the central satellite on each side;at least one feed horn coupled to the reflector; andsaid feed horn and the irregularly shaped contour including the plurality of areas cut from the reflector forming an antenna pattern including two pairs of nulls matched to said at least two pairs of satellites in the main beam, and the two pairs of nulls preventing signals from said at least two pairs of adjacent satellites from interfering with a signal being transmitted from the central satellite.