초록 ▼

A satellite communications employs separate subsystems for providing broadcast and point-to-point two-way communications using the same assigned frequency band. The broadcast and point-to-point subsystems employ an integrated satellite antenna system which uses a common reflector (12). The point-to-

A satellite communications employs separate subsystems for providing broadcast and point-to-point two-way communications using the same assigned frequency band. The broadcast and point-to-point subsystems employ an integrated satellite antenna system which uses a common reflector (12). The point-to-point subsystem achieves increased communication capacity through the reuse of the assigned frequency band over multiple, contiguous zones (32, 34, 36, 38) covering the area of the earth to be serviced. Small aperture terminals in the zones are serviced by a plurality of high gain downlink fan beams (29) steered in the east-west direction by frequency address. A special beam-forming network (98) provides in conjunction with an array antenna (20) the multiple zone frequency address function. The satellite (10) employs a filter interconnection matrix (90) for connecting earth terminals in different zones in a manner which permits multiple reuse of the entire band of assigned frequencies. A single pool of solid state transmitters allows rain disadvantaged users to be assigned higher than normal power at minimum cost. The intermodulation products of the transmitters are geographically dispersed.

대표청구항 ▼

A satellite communications system for communicatively interconnecting a plurality of terminal sites distributed over an area of the earth, comprising: an earth orbiting satellite; and frequency responsive means carried by said satellite for forming a plurality of beams of electromagnetic radiation b

A satellite communications system for communicatively interconnecting a plurality of terminal sites distributed over an area of the earth, comprising: an earth orbiting satellite; and frequency responsive means carried by said satellite for forming a plurality of beams of electromagnetic radiation between said area on the earth and said satellite with each beam of radiation having a carrier frequency, said beam forming means including an array of radiating elements and an antenna for producing all of said beams, said beams being arranged in at least two groups thereof respectively covering two essentially contiguous zones within said area, the beams in said groups thereof intersecting said area on the earth in seriatim along an arc with the position of each of said beams along said arc being determined by the carrier frequency of the beam, said groups of beams being arranged essentially end-to-end along said arc, the beams in each group thereof being carried by the same preselected set of frequencies such said set of frequencies is reused by said beams.