Satellite cluster with synchronized payload processors and method for use in space-based systems

• US 5,925,092 A
• Filed: 12/02/1996
• Issued: 07/20/1999
• Est. Priority Date: 12/02/1996
• Status: Expired due to Term

• Current Assignee: CDC Propriete Intellectuelle
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Swan, Peter Alfred, Haber, William Joe, Olds, Keith Andrew
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): ARTHUR JEANGLAUDE, GERTRUDE
• Application Number:
  US08/759,243
• Time in Patent Office: 960 Days
• Field of Search: 701/33, 701/213, 701/226, 455/3.2, 455/5.1, 455/12.1, 455/13.2, 342/357, 342/352, 364/131, 364/132, 364/133, 395/182.09, 395/182.1, 395/553
• US Class Current: 701/226
• CPC Class Codes: H04B 7/195 Non-synchronous stations

Abstract

A communication satellite system (100) includes one or more satellite clusters (150). Each satellite cluster (150) includes synchronized payload processors which are interconnected and synchronized into a parallel processing system using at least one crosslink (208) between multiple processor payload satellites (204). One element in the synchronized payload processors acts as a primary processor and other processor elements act as secondary processors. The primary processor controls and synchronizes the secondary processors. Various services which can include communication services, imaging services, and navigational services are provided to communication units (130) using at least one processor payload satellite (204) in satellite cluster (150). Two or more satellite clusters (150) are connected via a crosslink (138) which provides a communication and synchronization path between the satellite clusters (150).

Claims

1. A satellite cluster comprising:

a plurality of processor payload satellites, wherein said plurality of processor payload satellites contain payload processors each having at least one processor element, and said payload processors are interconnected and synchronized into a parallel processing system using at least one crosslink between said plurality of processor payload satellites, and a processor element of said at least one processor element acts as a primary processor in said parallel processing system and other processor elements act as secondary processors in said parallel processing system, and said primary processor controls and synchronizes said secondary processors, and at least one processor payload satellite of said plurality of processor payload satellites communicates with at least one ground device over a downlink between said at least one processor payload satellite and said at least one ground device.

2. The satellite cluster as claimed in claim 1, wherein said plurality of processor payload satellites are geosynchronous processor payload satellites.

3. The satellite cluster as claimed in claim 2, wherein said geosynchronous processor payload satellites are located within a common orbital slot.

4. The satellite cluster as claimed in claim 2, wherein said geosynchronous processor payload satellites are located close together.

5. The satellite cluster as claimed in claim 2, wherein said geosynchronous processor payload satellites are located in different orbits but in a substantially straight line with respect to a point on a surface of the earth.

6. The satellite cluster as claimed in claim 1, wherein said plurality of processor payload satellites are non-geosynchronous processor payload satellites.

7. The satellite cluster as claimed in claim 6, wherein said non-geosynchronous processor payload satellites are located substantially within a common orbit.

8. The satellite cluster as claimed in claim 6, wherein said non-geosynchronous processor payload satellites are located close together.

9. The satellite cluster as claimed in claim 6, wherein said non-geosynchronous processor payload satellites are located in different orbits but in a substantially straight line with respect to a point on a surface of the earth.

10. The satellite cluster as claimed in claim 1, wherein at least one of said plurality of processor payload satellites communicates with at least one other processor payload satellite in a different orbit over at least one additional crosslink.

11. A processor payload satellite for use in a satellite cluster, wherein said processor payload satellite comprises:

an antenna unit used to receive uplink signals transmitted from transmitting sources to said processor payload satellite, wherein said uplink signals cause a first number of computational tasks to be performed by synchronized payload processors of said satellite cluster, and said antenna unit is also used to transmit downlink signals from said processor payload satellite to receiving sources, wherein said downlink signals provide information which results from said first number of computational tasks being performed by said synchronized payload processors;

a transceiver coupled to said antenna unit, used to demodulate said uplink signals transmitted by said transmitting sources into uplink data and to convert downlink data into said downlink signals, wherein said uplink data is data which is used to perform said first number of computational tasks and said downlink data is data which results from a second number of computational tasks being performed;

a crosslink transceiver for converting crosslink transmitted data into crosslink transmitted signals and for converting crosslink received signals into crosslink received data, wherein said crosslink transmitted data is data which is sent to another satellite in said satellite cluster and is used to cause at least one processor element in said another satellite to perform at least a portion of said first number of computational tasks, and said crosslink received data is data which is received from said another satellite and which results from said at least a portion of said first number of computational tasks being performed;

a crosslink antenna unit for transmitting said crosslink transmitted signals and receiving said crosslink received signals, wherein said crosslink antenna unit is coupled to said crosslink transceiver; and

a payload processor coupled to said transceiver and said crosslink transceiver for processing said uplink data, processing said downlink data, processing said crosslink transmitted data, processing said crosslink received data, controlling performance of said first number of computational tasks, and performing at least one of said first number of computational tasks, wherein said payload processor includes a number of processor elements that can be controlled individually and can be included in said synchronized payload processors, wherein said controlling performance comprises determining if said first number of computational tasks must be performed by a multi-element processing system, causing said first number of computational tasks to be performed using said multi-element processing system when said determining step determines said first number of computational tasks must be performed by said multi-element processing system, and causing said first number of computational tasks to be performed using a single-element processing system when said determining step determines that said first number of computational tasks does not need to be performed by said multi-element processing system.

12. A processor payload satellite as claimed in claim 11 wherein said antenna unit further comprises:

a first antenna for transmitting first signals to and receiving second signals from a plurality of communication units; and

a second antenna for transmitting third signals to and receiving fourth signals from a system control center.

13. In a satellite communication system which uses a satellite cluster to provide communication services, a communication unit, which has been adapted to operate with said satellite cluster, comprising:

a transmitter to provide at least one uplink communication channel to said satellite cluster, wherein said transmitter transmits command signals to said satellite cluster causing synchronized payload processors of said satellite cluster to perform computational tasks, said command signals being used to determine if said computational tasks must be performed by a multi-element processing system, to cause said computational tasks to be performed using said multi-element processing system when said determining step determines said computational tasks need to be performed by said multi-element processing system, and to cause said computational task to be performed using a single-element processing system when said determining step determines that said computational tasks do not need to be performed by said multi-element processing system;

a receiver to provide at least one downlink communication channel from said satellite cluster wherein said receiver receives data signals from said satellite cluster resulting from said computational tasks performed by said synchronized payload processors; and

a processor coupled to said transmitter and said receiver for determining said command signals, for processing said data signals, and for controlling said transmitter, said receiver, and said communication unit.

14. In a satellite system which uses a satellite cluster, a method of operating a communication unit which has been adapted to operate with said satellite cluster, the method comprising the steps of:

transmitting uplink signals to a processor payload satellite in said satellite cluster, wherein said uplink signals contain command signals which cause synchronized payload processors in said satellite cluster to perform at least one computational task, said command signals being used to determine if said at least one computational task must be performed by a multi-element processing system, to cause said at least one computational task to be performed using said multi-element processing system when said determining step determines said at least one computational task needs to be performed by said multi-element processing system, and to cause said at least one computational task to be performed using a single-element processing system when said determining step determines that said at least one computational task does not need to be performed by said multi-element processing system;

receiving downlink signals from at least one processor payload satellite in said satellite cluster, wherein said downlink signals contain data signals from said satellite cluster which results from said at least one computational task being performed by said synchronized payload processors; and

processing said uplink signals and said downlink signals.

15. A method of operating a satellite cluster comprising the steps of:

receiving, at a first satellite, a request to perform a computational task;

determining if said computational task must be performed by a multi-element processing system;

causing said computational task to be performed using said multi-element processing system comprising multiple synchronized processing elements if said determining step determines said computational task must be performed by said multi-element processing system; and

causing said computational task to be performed using a single-element processing system comprising a single processing element if said determining step determines that said computational task does not need to be performed by said multi-element processing system.

16. The method as claimed in claim 15 wherein said step of causing said computational task to be performed using said single-element processing system further comprises the steps of:

selecting a processor payload satellite;

determining whether said computational task can be performed on said processor payload satellite;

causing said computational task to be performed when said computational task can be performed on said processor payload satellite;

determining whether another processor payload satellite is available, when said computational task cannot be performed on said processor payload satellite; and

when said another processor payload satellite is available, performing said computational task on said another processor payload satellite.

17. The method as claimed in claim 16 wherein said step of causing said computational task to be performed using said single element processing system further comprises the steps of:

storing results from performing said computational task when said computational task is performed on said processor payload satellite.

18. The method as claimed in claim 15 wherein said step of causing said computational task to be performed using said multi-element processing system further comprises the steps of:

selecting first and second processor payload satellites;

determining whether said computational task can be performed on said first and second processor payload satellites;

causing said computational task to be performed when said computational task can be performed on said first and second processor payload satellites;

determining whether another processor payload satellite is available, when said computational task cannot be performed on said first and second processor payload satellites; and

when said another processor payload satellite is available, using said another processor payload satellite to perform said computational task.

19. The method as claimed in claim 18 wherein said step of causing said computational task to be performed using said multi-element processing system further comprises the steps of:

storing results from performing said computational task when said computational task is performed on said first and second processor payload satellites.

20. The method as claimed in claim 15, wherein said step of causing said computational task to be performed using said multi-element processing system comprises the steps of:

dividing said computational task into individual tasks;

distributing said individual tasks to multiple satellite processors; and

collecting results of said individual tasks from said satellite processors.

21. In a satellite communication system which uses a satellite cluster to provide communication services, a method of operating a system control center which has been adapted to operate with said satellite cluster, the method comprising the steps of:

transmitting command signals to a processor payload satellite in said satellite cluster, wherein said command signals cause synchronized payload processors in said satellite cluster to perform at least one computational task, said command signals being used to determine if said at least one computational task must be performed by a multi-element processing system, to cause said at least one computational task to be performed using said multi-element processing system when said determining step determines said at least one computational task must be performed by said multi-element processing system, and to cause said at least one computational task to be performed using a single-element processing system when said determining step determines that said at least one computational task does not need to be performed by said multi-element processing system;

receiving response signals from said processor payload satellite in said satellite cluster, wherein said response signals contain data signals from said satellite cluster which resulted from said at least one computational task being performed by said synchronized payload processors; and

processing said command signals and said response signals to control operations being performed by said satellite cluster and to obtain data from said response signals.