Efficient Utilization of Orbit/Frequency for Satellite Broadcasting

In this paper some basic concepts involved in efficient orbit/spectrum utilization for broadcast satellites are discussed. A theoretical analysis leads to the determination of interference zones and minimum number of frequency channels required for homogeneous systems operating in the 800-MHz and 12-GHz bands. A crossed-beam arrangement of satellite systems is proposed, in which the beams from satellites to service areas cross each other. This arrangement has a more efficient orbit spectrum utilization compared to the identical-longitude approach, in which the subsatellite point has the same longitude as the center of the service area, Based upon practical considerations, the elemental number of frequency channels required for world-wide coverage has been calculated in relation to satellite orbital position, for single-beam and multibeam satellite systems, using the identical-longitude and crossed -beam arrangements.