Direct broadcast imaging satellite system apparatus and method for providing real-time, continuous monitoring of earth from geostationary earth orbit

• US 6,271,877 B1
• Filed: 06/25/1999
• Issued: 08/07/2001
• Est. Priority Date: 06/25/1999
• Status: Expired due to Fees

• Current Assignee: Astrovision International Incorporated
• Original Assignee: Astrovision, Inc.
• Inventors: LeCompte, Malcolm A.
• Primary Examiner(s): BRITTON, HOWARD W
• Application Number:
  US09/344,358
• Time in Patent Office: 774 Days
• Field of Search: H04/N.718, 348/144, 348/149, 348/208
• US Class Current: 348/144
• CPC Class Codes: G01C 11/025 by scanning the object

Abstract

A system, method and apparatus for collecting an distributing real-time, high resolution images of the Earth from GEO include an electro-optical sensor based on multi-megapixel two-dimensional charge coupled device (CCD) arrays mounted on a geostationary platform. At least four, three-axis stabilized satellites in Geostationary Earth orbit (GEO) provide worldwide coverage, excluding the poles. Image data that is collected at approximately 1 frame/sec, is broadcast over high-capacity communication links (roughly 15 MHZ bandwidth) providing real-time global coverage of the Earth at sub-kilometer resolutions directly to end users. This data may be distributed globally from each satellite through a system of space and ground telecommunication links. Each satellite carries at least two electro-optical imaging systems that operate at visible wavelengths so as to provide uninterrupted views of the Earth'"'"'s full disk and coverage at sub-kilometer spatial resolutions of most or selected portions of the Earth'"'"'s surface.

Claims

1. An imaging satellite configured to be placed in geostationary orbit, comprising:

an image sensor configured to be positioned toward Earth when in geostationary orbit and configured to produce data of a series of images of at least a portion of a surface of the Earth; and

a transmitter configured to transmit the data to a remote location so that said series of images may be viewed in real-time at said remote location, wherein

said series of images having respective resolutions that correspond with an image at nadir having at least a 500 m resolution when said satellite is positioned in geostationary orbit.

2. The imaging satellite of claim 1, wherein:

said image sensor includes a charge coupled device.

3. The imaging satellite of claim 2, wherein:

said charge coupled device having at least 1024×

1024 elements.

4. The imaging satellite of claim 3, wherein:

said charge coupled device having at least 2048×

2048 elements.

5. The imaging satellite of claim 4, wherein:

said charged coupled device includes at least 4096×

4096 elements.

6. The imaging satellite of claim 1, further comprising:

a scan system configured to change a relative position of the image sensor with regard to the surface of the Earth so that the image sensor perceives different portions of the Earth'"'"'s surface when producing the data of the series of images.

7. The imaging satellite of claim 6 further comprising:

an optics subsystem configured to adjust a field of view observed by said image sensor when producing said data of the series of images.

8. The imaging satellite of claim 6, wherein:

said scan system includes a motor-actuated mirror configured to adjust an optics path that impinges on said image sensor by adjusting a relative position of the motor-actuated mirror with respect to the image sensor.

9. The imaging satellite of claim 6, wherein:

said scan system includes a control mechanism configured to control an amount of spin imparted by a momentum wheel on said satellite so as to impart a relative rotation of the satellite with respect to the Earth and cause an optical path of said image sensor to change with respect to a predetermined spot on Earth.

10. The imaging satellite of claim 6, wherein:

said scan system includes a controller that is configured to adjust a scanning operation of said scan system to cause said image sensor to produce said series of images according to a step-stare pattern.

11. The imaging satellite of claim 6, further comprising:

a software reconfigurable processor that is configured control said scan system to perform at least one of a full scan raster operation, perform a geo-reference tracking operation, and dwell at a predetermined portion on the surface of the Earth for a predetermined dwell time.

12. The imaging satellite of claim 1, wherein:

said transmitter includes a data compression mechanism configured to compress the data before transmitting the data to said remote location.

13. The imaging satellite of claim 1, wherein:

said image sensor being configured to produce the images of the surface of the Earth, at night.

14. The imaging satellite of claim 1, wherein:

said transmitter being configured to transmit said data to another satellite via a cross-link.

15. The imaging satellite of claim 1, wherein:

said transmitter being configured to transmit said data directly to a ground terminal.

16. The imaging satellite of claim 1, wherein:

said transmitter being configured to transmit said data to said remote location by way of a terrestrial communication network.

17. The imaging satellite of claim 1, wherein:

said transmitter being configured to transmit said data to a network node configured to relay said data to said remote location by way of an Internet.

35. The imaging satellite of claim 1, wherein:

said image sensor being configured to produce said data of a series of color images.

18. A constellation of at least four imaging satellites in geostationary orbit, each satellite comprising:

an image sensor positioned toward Earth and configured to produce data of a series of images of at least a portion of a surface of the Earth that have respective resolutions equating to 500 m or better if taken at nadir; and

a transmitter configured to transmit the data to a remote location so that said series of images may be viewed in real-time at said remote location, wherein

each of said at least four satellites being configured to communicate with ground facilities located within line of sight of respective of the at least four satellites.

19. The constellation of claim 18, further comprising:

at least one communication satellite configured to receive and route the data to the remote location by way of a ground-based teleport.

20. A method for capturing and distributing real-time image data from geostationary orbit, comprising steps of:

forming a series of images of at least a portion of a surface of Earth, including

forming the series of images at a frame rate of 1 second per frame or faster, and

forming the series of images that have respective resolutions equating to 500 m or better if taken at nadir;

producing a stream of data representative of the series of images; and

transmitting the data to a remote location.

21. The method of claim 20, further comprising:

a step of receiving the data at the remote location and producing the images from the data for real-time viewing.

22. The method of claim 20, wherein:

said step of forming a series of images includes scanning an image sensor over a field of view that includes a predetermined portion of the surface of the Earth so as to produce the series of images at different locations on the surface of the Earth.

23. The method of claim 22, wherein:

said step of forming a series of images includes adjusting a field of view of the image sensor by adjusting an optical path to the image sensor.

24. The method of claim 23, wherein:

said scanning step includes adjusting a relative position of a mirror with respect to said image sensor to change an optical path leading to said image sensor.

25. The method of claim 23, wherein:

said step of scanning includes adjusting a speed of a satellite-based momentum wheel.

26. The method of claim 23, wherein:

said scanning step includes scanning said image sensor to form a step-stare series of images.

27. The method of claim 20, wherein:

said step of forming a series of images includes controlling an image sensor to perform at least one of a full scan raster operation, a geo reference tracking operation, and a dwell point adjustment operation.

28. The method of claim 20, wherein:

said transmitting step includes compressing the data.

29. The method of claim 20, wherein:

said step of forming a series of images, includes forming the series of images at night.

30. The method of claim 20, wherein:

said transmitting step includes transmitting the data to another satellite via a crosslink.

31. The method of claim 20, wherein:

said transmitting step includes transmitting said data directly to a ground terminal.

32. The method of claim 20, wherein:

said receiving step includes receiving the data at a remote location by way of a terrestrial communication network.

33. The method of claim 32, wherein:

said receiving step includes receiving the data through an Internet, as said terrestrial communication network.

36. The method of claim 20, wherein:

said step of forming the series of images comprises forming said series of images in color.

34. An imaging satellite configured to be in geostationary orbit, comprising:

means for forming a series of images of at least a portion of a surface of Earth, including

means for forming the series of images at a frame rate that is one second or less,

means for forming the series of images with respective resolutions equating to at least 500 m if taken at nadir;

means for producing a stream of data that represents the series of images; and

means for transmitting the data to a remote location.

37. The imaging satellite of claim 34, wherein:

said means for forming a series of images comprises means for forming color images.

38. A system for distributing data of a series of images having respective resolutions equating to at least 500 m resolution if taken at nadir from an imaging satellite in geostationary orbit to a remote location, comprising:

an imaging device configured to capture in memory said series of images at a real-time rate;

a transmitter configured to transmit said data of said series of images to a remote location so that said series of images may be viewed in real-time at said remote location.

39. The system of claim 38, wherein:

said imaging device includes a charge-coupled device.

40. The system of claim 39, wherein:

said charge-coupled device having at least 1024×

1024 elements.

41. The system of claim 40, wherein:

said charge-coupled device having at least 2048×

2048 elements.

42. The system of claim 41, wherein:

said charged-coupled device having at least 4096×

4096 elements.

43. The system of claim 39, wherein:

said charge-coupled device being configured to be controllably oriented at a relative position with regard to a surface of Earth by a scan system so that said charge-coupled device perceives different portions of the surface of Earth when producing the data for said series of images.

44. The system of claim 39, wherein:

said charge-coupled device being configured to have a field of view observed by said charge-coupled device changed by an optical subsystem when producing said data for said series of images.

45. The system of claim 43, wherein:

said scan system including a motor-actuated mirror configured to adjust an optical path of rays that impinge on said charge-coupled device by adjusting a relative position of the motor-actuated mirror with respect to said charge-coupled device.

46. The system of claim 43, wherein:

said scan system including a control mechanism configured to control an amount of spin imparted by a momentum wheel on said satellite so as to impart a relative rotation of the satellite with respect to Earth and cause an optical path of rays that impinge upon said charge-coupled device to change with respect to a predetermined spot on Earth.

47. The system of claim 43, wherein:

said scan system including a controller that is configured to adjust a scanning operation of said scan system to cause said charge-coupled device to produce said series of images according to a step-stare pattern.

48. The system of claim 43, wherein:

said scan system being controlled by a software reconfigurable processor to perform at least one of a full scan raster operation, perform a geo-reference tracking operation, and dwell at a predetermined portion on the surface of the Earth for a predetermined dwell time.

49. The system of claim 38, wherein said transmitter includes:

a data compression mechanism configured to compress the data before transmitting the data to said remote location.

50. The system of claim 39, wherein:

said charge-coupled device being configured to produce said series of images of the surface of the Earth at night.

51. The system of claim 38, wherein:

said transmitter being configured to transmit said data to another satellite via a cross-link.

52. The system of claim 38, wherein:

said transmitter being configured to transmit said data directly to a ground terminal.

53. The system of claim 38, wherein:

said transmitter being configured to transmit said data to said remote location by way of a terrestrial communication network.

54. The system of claim 38, wherein:

said transmitter being configured to transmit said data to a network node configured to relay said data to said remote location by way of an Internet.