Aircraft bird strike avoidance method and apparatus

• US 8,570,211 B1
• Filed: 01/19/2010
• Issued: 10/29/2013
• Est. Priority Date: 01/22/2009
• Status: Active Grant

• Current Assignee: Gregory Hubert Piesinger
• Original Assignee: Gregory Hubert Piesinger
• Inventors: Piesinger, Gregory Hubert
• Primary Examiner(s): Keith, Jack W
• Assistant Examiner(s): BYTHROW, PETER M
• Application Number:
  US12/657,318
• Time in Patent Office: 1,379 Days
• Field of Search: 342 29- 32
• US Class Current: 342/29
• CPC Class Codes: G01S 13/003 Bistatic radar systems; Multistatic radar systems
• CPC Class Codes: G01S 13/284 using coded pulses
• CPC Class Codes: G01S 13/48 using multiple beams at emission or reception
• CPC Class Codes: G01S 13/933 of aircraft or spacecraft
• CPC Class Codes: G01S 2013/468 by Triangulation, i.e. two antennas or two sensors determine separately the bearing, direction or angle to a target, whereby with the knowledge of the baseline length, the position data of the target is determined
• CPC Class Codes: G01S 7/415 Identification of targets based on measurements of movement associated with the target

Abstract

A non-scanning radar system is installed on an aircraft to detect and avoid bird strikes or collisions with other airborne hazards. Target amplitude, range, and Doppler tracking versus time are used to qualify the collision threat. Avoidance is based on a quick minor altitude change by the pilot or autopilot to exit the imminent bird or other airborne hazard altitude window. In one embodiment, a bistatic passive radar receiver antenna is used in conjunction with an existing geostationary satellite signal. Range and Doppler information are obtained via cross correlation processing of the hazard reflection signal with a direct path reference signal from the satellite.

Claims

1. A method for detecting and avoiding an aircraft collision with birds, said method comprising:

providing at least one non-scanning antenna on said aircraft;

illuminating a surveillance volume ahead of said aircraft with a radar signal;

receiving reflections of said radar signal from radar targets at least as small as birds in said surveillance volume, said receiving operation being performed by the same or a different one of said at least one non-scanning antenna on said aircraft;

measuring target parameters of said radar targets, said target parameters include at least range, amplitude, and Doppler shift of each said radar targets;

determining the collision threat probability of said aircraft with said radar targets, said collision threat probability determined by the variation of said target parameters with time;

alerting the pilot of a collision threat when said collision threat probability exceeds a predetermined threshold; and

maneuvering said aircraft to avoid colliding with said birds when alerted of said collision threat, said maneuvering operation being performed by said pilot or an aircraft autopilot.

2. A method as claimed in claim 1 wherein said collision threat probability exceeds said predetermined threshold when a target normalized said amplitude is nearly constant as said range to said target decreases.

3. A method as claimed in claim 1 wherein said collision threat probability exceeds said predetermined threshold when a target said Doppler shift is nearly constant as said range to said target decreases.

4. A method as claimed in claim 1 wherein said radar signal is transmitted and said reflections are received using the same or different said non-scanning antenna on said aircraft.

5. A method as claimed in claim 1 wherein said radar signal is transmitted from a geostationary satellite and said reflections are received using at least one said non-scanning antenna on said aircraft.

6. A method as claimed in claim 5 wherein said geostationary satellite is at least one XM satellite radio geostationary satellite.

7. A method as claimed in claim 5 wherein said geostationary satellite is at least one Fixed Satellite Services or Broadcasting Satellite Services geostationary communications satellite.

8. A method as claimed in claim 5 wherein said radar signal is an existing broadcast signal from said geostationary satellite.

9. A method as claimed in claim 1 wherein said radar signal is a continuous wave pseudo random noise coded pulse compression waveform.

10. A method as claimed in claim 1 further including receiving a non-reflected said radar signal and cross correlating said non-reflected radar signal with a reflected said radar signal from a target to measure said target parameters.

11. A method as claimed in claim 1 further including separating a pair of said non-scanning antenna on said aircraft horizontally or vertically and determining said collision threat probability of said radar targets by triangulation.

12. An apparatus for detecting and avoiding an aircraft collision with birds, said apparatus comprising:

one or more non-scanning antennas mounted on said aircraft and configured to observe an airborne surveillance volume ahead of said aircraft;

a transmitter configured to illuminate said surveillance volume with a radar signal;

receivers coupled to each said antennas and configured to receive reflections of said radar signal from radar targets at least as small as birds;

a signal detection processor coupled to said receivers and configured to detect and process said reflections from said radar targets;

a target processor coupled to said signal detection processor and configured to determine if said radar targets represents a collision threat between said aircraft and said birds; and

means for communicating said collision threat to said aircraft pilot or said aircraft autopilot,

whereby said pilot or said autopilot can maneuver said aircraft to avoid a collision with said birds.

13. An apparatus as in claim 12 wherein said signal detection processor includes a plurality of filters matched to different Doppler offset frequencies of said reflections of said radar signal from said radar targets.

14. An apparatus as in claim 12 wherein said signal detection processor includes a signal detector configured to measure target parameters of said radar targets, said target parameters include at least range, amplitude, and Doppler shift of each said radar targets.

15. An apparatus as in claim 12 wherein a target is determined to be said collision threat when the normalized said target amplitude is essentially constant as said target range to said target decreases.

16. An apparatus as in claim 12 wherein a target is determined to be said collision threat when said target Doppler shift is essentially constant as said target range to said target decreases.

17. An apparatus as in claim 12 wherein said transmitter is located on a geostationary satellite.

18. An apparatus as in claim 17 wherein said radar signal is said geostationary satellite existing broadcast signal.