System for measuring turbulence remotely

• US 20060121893A1
• Filed: 12/03/2004
• Published: 06/08/2006
• Est. Priority Date: 12/03/2004
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Tillotson, Brian J., Spinelli, Charles B.
• Granted Patent: US 7,598,901 B2
• Time in Patent Office: Days
• US Class Current: 455/431
• CPC Class Codes: G01P 5/001 Full-field flow measurement, e.g. determining flow velocity and direction in a whole region at the same time, flow visualisation
• CPC Class Codes: G01P 5/26 by measuring the direct influence of the streaming fluid on the properties of a detecting optical wave
• CPC Class Codes: G01S 13/955 mounted on satellite
• CPC Class Codes: G01W 1/16 Measuring atmospheric potential differences, e.g. due to electrical charges in clouds measuring potentiels in general G01R
• CPC Class Codes: G01W 2001/003 Clear air turbulence detection or forecasting, e.g. for aircrafts
• CPC Class Codes: G08G 5/0021 located in the aircraft
• CPC Class Codes: G08G 5/0091 for monitoring atmospheric conditions radar or analogous systems specially adapted for meteorological use G01S13/95; meteorology G01W
• CPC Class Codes: Y02A 90/10 Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Abstract

A system and method for detecting turbulence includes several mobile platforms, a mobile platform velocity sensor, and several electromagnetic energy transmitters and receivers. The receivers receive the energy transmitted by the transmitter(s) after it has traveled along a path subject to the turbulence. The receivers detect alterations of the energy caused by the turbulence and filter the alterations for effects of the mobile platform velocity (on which either a transmitter or receiver is located). Additionally, the system may create a three-dimensional model of the. In another preferred embodiment, the present invention provides a method of detecting turbulence using a mobile platform. The method includes receiving electromagnetic energy that has traveled along a path subject to the turbulence and determining the alteration to the energy caused by the turbulence. The alterations are filtered of the effects of the velocity of the mobile platform on which the receivers are preferably located.

Claims

1. A receiver of electromagnetic energy that travels along a path and is incident on an antenna, the antenna being responsive to incident electromagnetic energy to produce a received signal, the path being subject to turbulence, the receiver comprising:

an input to accept the received signal;

a circuit in communication with the input, the circuit to accept the received signal and to accept a signal that is representative of a velocity of a mobile platform, at least one of the receiver and a source of the electromagnetic energy being on the mobile platform, the circuit to process the received signal using the velocity signal to remove a shift associated with the received signal because of relative motion between the source and the receiver, the circuit thereby determining an alteration of the electromagnetic energy caused by the turbulence; and

an output in communication with the circuit to output a signal that is representative of the turbulence.

2. The receiver according to claim 1, further comprising the circuit to accept a signal that is representative of a heading of the mobile platform and to determine a direction to the source of the electromagnetic energy using the heading signal.

3. The receiver according to claim 1, wherein the velocity includes at least one of a linear velocity or an angular velocity.

4. The receiver according to claim 1, wherein the turbulence includes an ionospheric turbulence and a tropospheric turbulence, the receiver further comprising the circuit to determine an alteration of the electromagnetic energy caused by the ionospheric turbulence and to process the received signal using the alteration of the electromagnetic energy caused by the ionospheric turbulence, the output signal being representative of the tropospheric turbulence.

5. The receiver according to claim 1, wherein the receiver further comprises a global positioning system receiver.

6. The receiver according to claim 1, further comprising a coupler to couple the receiver to the mobile platform.

7. The receiver according to claim 1, the received signal being representative of the incident electromagnetic energy at a first location and being a first received signal, the alteration being a first alteration, the circuit further comprising being adapted to accept a second received signal from a second antenna, the second antenna being at a second location, the circuit to process the second received signal using the velocity signal to remove a shift associated with the second received signal because of relative motion between the source and the receiver, the circuit thereby determining a second alteration of the electromagnetic energy caused by the turbulence.

8. The receiver according to claim 7, further comprising the circuit to correlate the first alteration of the electromagnetic energy and the second alteration of the electromagnetic energy.

9. The receiver according to claim 8, further comprising the output signal being further representative of the correlation between the first alteration of the electromagnetic energy and the second alteration of the electromagnetic energy.

10. The receiver according to claim 1, wherein the source is a satellite.

11. The receiver according to claim 1, further comprising the circuit to determine at least one of a phase difference, an intensity difference, or a frequency difference in determining the alteration of the electromagnetic energy.

12. A mobile platform comprising:

at least one antenna responsive to incident electromagnetic energy to produce a received signal, the electromagnetic energy to travel along a path that is subject to turbulence;

a sensor to determine the velocity of the mobile platform; and

a receiver in communication with the antenna and the sensor, the receiver including;

an input to accept the received signal and to accept a signal from the sensor that is representative of the velocity;

a circuit in communication with the input, the circuit to process the received signal using the velocity signal to remove a shift associated with the received signal because of relative motion between a source of the electromagnetic energy and the receiver, the circuit thereby determining an alteration of the electromagnetic energy caused by the turbulence; and

an output in communication with the circuit to output a signal that is representative of the turbulence.

13. The mobile platform according to claim 12, further comprising a sensor to determine a heading of the mobile platform, the input to accept a signal from the heading sensor that is representative of the heading, the circuit to determine a direction to a source of the electromagnetic energy using the heading signal.

14. The mobile platform according to claim 12, the alteration being a first alteration, the antenna being a first antenna at a first location on the mobile platform, the received signal being a first received signal, the mobile platform further comprising a second antenna responsive to incident electromagnetic energy to produce a second received signal, the second antenna being at a second location on the mobile platform, the circuit to accept the second received signal and to process the second received signal using the velocity signal to remove a shift associated with the received signal because of relative motion between the source and the receiver, the circuit thereby determining a second alteration of the electromagnetic energy caused by the turbulence.

15. The mobile platform according to claim 14, further comprising the circuit to correlate the first alteration of the electromagnetic energy and the second alteration of the electromagnetic energy.

16. The mobile platform according to claim 15, further comprising the circuit to further correlate the first alteration of the electromagnetic energy and the second alteration of the electromagnetic energy using a time period defined by a distance between the first location and the second location and the velocity signal.

17. The mobile platform according to claim 16, further comprising the output signal being further representative of the correlation between the first alteration of the electromagnetic energy received and the second alteration of the electromagnetic energy.

18. The mobile platform according to claim 12, wherein the source is a satellite.

19. The mobile platform according to claim 12, wherein the mobile platform is an aircraft.

20. The mobile platform according to claim 12, further comprising a sidewall, the antenna having a field of view that forms an acute angle with the side wall.

21. The mobile platform according to claim 12, wherein the antenna is adapted to accept low elevation signals.

22. A system for detecting turbulence comprising:

at least one mobile platform;

a sensor to determine a velocity of the at least one mobile platform;

at least one transmitter to transmit electromagnetic energy along a path that is subject to turbulence; and

at least one receiver to receive the electromagnetic energy, at least one of the transmitter and the receiver being on the mobile platform, the receiver including an antenna responsive to incident electromagnetic energy to produce a received signal, the receiver to accept a signal from the sensor that is representative of the velocity, the receiver to process the received signal using the velocity signal to remove a shift associated with the received signal because of relative motion between a source of the electromagnetic energy and the receiver, the receiver thereby determining an alteration of the electromagnetic energy caused by the turbulence;

the receiver to output a signal that is representative of the turbulence.

23. The system according to claim 22, wherein a first mobile platform of the mobile platforms being selected from the group consisting of an aircraft, a satellite, a land vehicle, a marine vehicle.

24. The system according to claim 22, further comprising a processor to receive the output signal and to create a three dimensional model of the turbulence using the output signal.

25. The system according to claim 24, wherein the three dimensional model is a tomographic model.

26. The system according to claim 24, further comprising a network in communication with the processor, the processor to distribute the three dimensional model of the turbulence via the network.

27. The system according to claim 26, the network further comprising a subscribe-publisher architecture.

28. The system according to claim 26 further comprising an air traffic control system in communication with the network.

29. The system according to claim 24, wherein the processor determines a statistical confidence interval associated with the three dimensional model.

30. The system according to claim 24, further comprising at least one meteorological sensor communicating with the processor, the processor to determine a meteorological prediction based on a condition sensed by the sensor and to augment the three dimensional model of the turbulence with the meteorological prediction.

31. The system according to claim 24, further comprising at least one meteorological model accessible by the processor, the processor to determine a meteorological prediction based on the model and to augment the three dimensional model of the turbulence with the meteorological prediction.

32. The system according to claim 24, the at least one mobile platform further comprising an mobile platform including at least one of an air data sensor or an inertial sensor, the at least one sensor in communication with the processor and to generate fourth signal, the processor to use the fourth signal to augment the three dimensional model of the turbulence.

33. The system according to claim 22, wherein the at least one mobile platform includes at least one of a ground vehicle or a marine vehicle.

34. The system according to claim 22, wherein the receiver is on the mobile platform.

35. The system according to claim 22, wherein the output signal includes a location of the receiver, a direction associated with the electromagnetic energy, and a time associated with the reception of the electromagnetic energy.

36. The system according to claim 22, wherein the transmitter is near the horizon as viewed from the receiver.

37. The system according to claim 22, wherein the at least one mobile platform is in a pre-selected geographic region.

38. The system according to claim 37, wherein the geographic region includes at least one of an approach path to an airport or a departure path from the airport.

39. The system according to claim 22, further comprising the antenna being a first antenna, the received signal being a first received signal, the receiver including a second antenna, the receiver and the first antenna and the second antenna to be on the mobile platform, the path being between the transmitter and the first antenna and being a first path, a second path being between the second antenna and the transmitter, the first antenna and the second antenna in communication with the at least one receiver, the second antenna being responsive to incident electromagnetic energy to produce a second received signal, the receiver to process the second received signal using the velocity signal to remove a shift associated with the second received signal because of relative velocity between the source of the electromagnetic energy and the receiver, the receiver thereby determining a second alteration of the electromagnetic energy caused by the turbulence

40. The system according to claim 39, further comprising the circuit to correlate the first alteration of the electromagnetic energy and the second alteration of the electromagnetic energy.

41. The system according to claim 40, further comprising the first antenna and the second antenna being spaced apart by a distance, the circuit to further correlate the first alteration of the electromagnetic energy and the second alteration of the electromagnetic energy using a time period defined by the distance and the velocity of the mobile platform.

42. A method of predicting turbulence comprising:

receiving electromagnetic energy that has traveled along a path subject to the turbulence, the turbulence altering the electromagnetic energy; and

determining the alteration caused by the turbulence by filtering the electromagnetic energy as it was received with a velocity of one of a transmitter of the electromagnetic energy or a receiver that received the electromagnetic energy.

43. The method according to claim 42, further comprising determining a direction between the receiver and the transmitter.

44. The method according to claim 42, wherein the velocity includes at least one of a linear velocity or an angular velocity.

45. The method according to claim 42, the turbulence including an ionospheric turbulence and a tropospheric turbulence, the method further comprising determining a portion of the alteration of the electromagnetic energy caused by the tropospheric turbulence.

46. The method according to claim 42, further comprising coupling at least one of the receiver and the transmitter to a mobile platform.

47. The method according to claim 42, wherein the receiving the electromagnetic energy being at a first location, the alteration of the electromagnetic energy being a first alteration of the electromagnetic energy, the method further comprising receiving the electromagnetic energy at a second location and determining a second alteration of the electromagnetic energy caused by the turbulence by filtering the electromagnetic energy as it was received at the second location with the velocity.

48. The method according to claim 47, further comprising correlating the first alteration of the electromagnetic energy and the second alteration of the electromagnetic energy.

49. The method according to claim 48, further comprising the correlating including accounting for a time difference between the receiving of the electromagnetic energy at the first location and the receiving of the electromagnetic energy at the second location, the time difference being defined by the velocity and a distance between the first location and the second location.

50. The method according to claim 42, the receiving the electromagnetic energy further comprising being from a satellite.

51. The method according to claim 42, the determining the alteration of the electromagnetic energy further comprising detecting at least one of a phase difference, an intensity difference, or a frequency difference.

52. The method according to claim 42, further comprising creating a three dimensional model of the turbulence.

53. The method according to claim 52, wherein the three dimensional model is a tomographic model.

54. The method according to claim 52, further comprising distributing the three dimensional model via a network.

55. The method according to claim 52 further comprising at least one of subscribing to or publishing the three dimensional model.

56. The method according to claim 52, further comprising determining a statistical confidence interval associated with the three dimensional model.

57. The method according to claim 52, further comprising augmenting the three dimensional model with a meteorological prediction.

58. The method according to claim 52, further comprising collecting turbulence data with a sensor in the turbulence and augmenting the three dimensional model with the data.

59. The method according to claim 42, wherein the turbulence is associated with an airport.

60. The method according to claim 42, further comprising accepting the receiving of the electromagnetic energy at a low elevation.

61. The method according to claim 42, further comprising avoiding the turbulence that caused the alteration to the electromagnetic energy.

62. The method according to claim 42, further comprising issuing a warning based on the alteration that caused the alteration to the electromagnetic energy.

63. A computer readable medium having executable instructions stored thereon for causing the computer to:

accept a plurality of one-dimensional measurements of turbulence, each of the plurality of measurements being taken along a path, at least one measurement of the plurality of measurements being adjusted for a velocity associated with a system that made the at least one measurement;

determine an approximate intersection of at least two of the paths;

determine the amount of turbulence at the approximate intersection; and

indicate the amount of turbulence at the approximate intersection.

64. The medium according to claim 63, wherein a location is associated with each of the measurements.

65. The medium according to claim 63, wherein a heading associated with the system is associated with each of the measurements.

66. The medium according to claim 63, wherein the plurality of measurements have been adjusted to remove an affect of ionospheric scintillation.

67. The medium according to claim 63, wherein the plurality of measurements are derived from a plurality of GPS signals.

68. The medium according to claim 63, wherein the plurality of one-dimensional measurements is a first plurality, the medium further having executable instructions stored thereon for causing the computer to accept a second plurality of one-dimensional measurements of the turbulence.

69. The medium according to claim 68, further having executable instructions stored thereon for causing the computer to correlate the first plurality of measurements and the second plurality of measurements.

70. The medium according to claim 68, wherein the first plurality of measurements and the second plurality of measurements are separated by a time period associated with the velocity of the system.

71. The medium according to claim 63 wherein the plurality of measurements are derived from at least one of a phase difference, an intensity difference, or a frequency difference.

72. The medium according to claim 63 wherein an elevation angle is associated with each of the measurements, at least one elevation angle being low.

73. The medium according to claim 63, wherein the model is a tomographic model.

74. The medium according to claim 63, further having executable instructions stored thereon for causing the computer to limit the model to a pre-selected geographic limit.

75. The medium according to claim 63, further having executable instructions stored thereon for causing the computer to accept turbulence information from a source external to the model and to augment the model with the information.

76. The medium according to claim 75, wherein the source is at least one of a meteorological sensor, a meteorological prediction, an air data sensor, or an inertial sensor.

77. The medium according to claim 63, further having executable instructions stored thereon for causing the computer to create an overlay for displaying the indication of the amount of the turbulence.

78. The medium according to claim 63, further having executable instructions stored thereon for causing the computer to determine a statistical confidence interval associated with the amount of the turbulence.

79. A computer readable medium having executable instructions stored thereon for causing the computer to:

accept a received signal wherein the received signal is produced by an antenna that is responsive to incident electromagnetic energy, the electromagnetic energy to travel along a path that is subject to turbulence;

accept a signal that is representative of a velocity of a mobile platform, at least one of the antenna and a source of the electromagnetic energy being on the mobile platform;

process the received signal using the velocity signal to remove a shift associated with the received signal because of relative motion between the source and the antenna thereby determining an alteration of the electromagnetic energy caused by the turbulence; and

output a signal that is representative of the turbulence.