Satellite arrangement providing effective use of the geostationary orbit

• US 4,375,697 A
• Filed: 09/04/1980
• Issued: 03/01/1983
• Est. Priority Date: 09/04/1980
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Visher, Paul S.
• Primary Examiner(s): Safourek, Benedict V.
• Application Number:
  US06/183,883
• Time in Patent Office: 908 Days
• Field of Search: 343/100 R, 343/100 ST, 370/104, 455/12, 455/13, 455/25, 455/54, 455/600, 455/601
• US Class Current: 455/13.1
• CPC Class Codes: H04B 7/18521 Systems of inter linked satellites, i.e. inter satellite service for optical links between satellites H04B10/118
• CPC Class Codes: H04B 7/19 Earth-synchronous stations

Abstract

A satellite squadron or cluster formation is disposed in a predetermined location in the geostationary orbit, including a plurality of controllably maneuverable communication satellites and a centrally located switching and control satellite. The satellites comprise a simulated geostationary communications platform made up of discrete modules which are not physically attached together. The satellites are grouped together in assigned positions in a relatively close formation, and are provided with cross-link intersatellite radio communications. The switching and control satellite detects the relative position of the communication satellites and sends control signals to maintain them in their assigned positions in the formation. Communication signals are relayed from one place on the earth to another via the satellite cluster formation by utilizing the control satellite as a switching satellite. Each satellite has a communications down link providing communications with selected earth stations in a predetermined frequency band. When a signal is received by one of the satellites, it converts the signal to the cross-link frequency band and transmits it to the control satellite, which retransmits the signal to a different satellite, where it is converted to that satellite'"'"'s down link frequency band, and retransmitted to the earth. In this manner, a signal originating in one continent, for example, may travel to the satellite cluster at one frequency band, and may be relayed to another continent at another frequency band. Thus, all satellite earth stations at their various frequency bands are mutually compatible.

Claims

1. A satellite arrangement comprising:

a plurality of controllably maneuverable satellites disposed at a predetermined location of a geostationary orbit;

said satellites being grouped in assigned positions relative to each other to form a cluster of satellites at said location in a predetermined formation;

at least one of said satellites being a control satellite and the remainder of said satellites being communications satellites;

means on said satellites providing communication across links between said satellites for providing intercommunication between said control satellite and each of said communications satellites at selected cross link frequencies;

means on said control satellite for detecting errors in the position of individual communication satellites relative to said control satellite and for controlling the position of each communication satellite, over said communication cross links, to maintain said predetermined formation;

communications down link means disposed on said satellites for providing intercommunication with selected earth stations at selected down link frequencies;

means disposed on said satellites for interconnecting said communications down link means with said communications cross link means, including means for converting between said down link frequencies and said cross link frequencies; and

means disposed on said control satellite for relaying cross link signals received from one of said communications satellites to selected different ones of said communications satellites.

2. The satellite arrangement of claim 1 in which said communications down link means includes a large aperture high gain antenna and a multiplicity of antenna feeds to provide a plurality of narrow spot antenna beams for each of said communications satellites.

3. The satellite arrangement of claim 2 in which said communications down link means and said communications cross link means include solely solid state circuits.

4. The satellite arrangement of claim 3 in which said communications down link means and said communications cross link means include transmitters of solely low power output.

5. A simulated geostationary communications platform comprising:

a plurality of controllably maneuverable communications satellites disposed at a predetermined location of a geostationary orbit, said communications satellites being provided with means for communicating with selected earth stations over communications down links at selected down link frequencies;

at least one switching and control satellite disposed among said communication satellite at said predetermined location of said geostationary orbit;

said communications satellites and said switching and control satellite being provided with means for communication between said switching and control satellite and each of said communications satellites over individual communications cross links at selected cross link frequencies, each of said communications satellites being provided with means for converting signals between said down link frequencies and said cross link frequencies, said switching and control satellite being provided with controllable means for selectively relaying cross link signals received from one said communications satellites to selected ones of said other communications satellites;

position error detecting means coupled to said individual communication cross links; and

means on said switching and control satellite responsive to said position error detecting means for transmitting position command signals on said individual communication cross links to maneuver and group said communications satellites relative to said switching and control satellite to form a cluster of satellites in a predetermined formation.

6. A satellite arrangement comprising:

a plurality of controllably maneuverable communications satellites and a control satellite adapted to be disposed at a predetermined location of a geostationary orbit in assigned positions in a predetermined formation to form a cluster of satellites at that location;

means providing communication cross links disposed on said satellites for providing intercommunication between said control satellite and each of said communications satellites at selected cross link frequencies;

said control satellite controlling the individual spatial positions of said communication satellites relative to said control satellites over said communication cross links to maintain said satellites in said predetermined formation;

communications down link means disposed on said satellites for providing intercommunication with selected earth stations at selected down link frequencies;

means disposed on said satellites for interconnecting said communications down link means with said communications cross link means, including means for converting between said down link frequencies and said cross link frequencies; and

means disposed on said control satellite for relaying cross link signals received from one of said satellites to selected ones of said other satellites.

7. A simulated geostationary communications platform comprising:

a plurality of controllably maneuverable earth transmit/receive satellites adapted to be disposed at a predetermined location in the geostationary orbit;

a switching and control satellite located at said predetermined location in the geostationary orbit;

said earth transmit/receive satellites and said switching and control satellite being disposed relative to each other to form a cluster of satellites in a predetermined formation;

each of said earth transmit/receive satellites being provided with a radio communications cross link with said switching and control satellite in at least a first predetermined cross link frequency band, said communications cross link comprising directive antennas, low power solid transmitters, and solid state receivers;

ranging and position detecting means disposed on said switching and control satellite for detecting the location of each of said earth transmit/receive satellites relative to said switching and control satellite;

command means disposed on said switching and control satellite and responsive to said ranging and position detecting means for providing correction signals to said earth transmit/receive satellites via said communications cross link to control and maintain each of said earth transmit/receive satellites in its assigned position in said predetermined formation; and

each of said earth transmit/receive satellites being provided with a communications down link in at least a second predetermined frequency band, said communications down link comprising a high gain antenna, a plurality of low power solid state transmitters, a plurality of antenna feeds, and a plurality of solid state receivers.

8. A satellite squadron arrangement comprising:

a plurality of controllably maneuverable satellites adapted to be disposed in a predetermined orbit, said satellites being grouped in assigned positions relative to each other to form a cluster of satellites in a predetermined formation, at least one of said satellites being a control satellite;

communications cross link means disposed on said satellites for providing intercommunication therebetween;

means for developing error signals at said control satellites indicative of deviations of said satellites from their assigned positions in said predetermined formation; and

means disposed on said control satellite and responsive to said last-named means for developing command signals for transmission over said communications cross link means to controllably maneuver said satellites to correct for said deviations and maintain said satellites in said positions in said predetermined formation.