Systems and methods for coordination of entities and/or communicating location information

• US 7,894,948 B2
• Filed: 11/01/2007
• Issued: 02/22/2011
• Est. Priority Date: 11/01/2007
• Status: Active Grant

• Current Assignee: L3harris Technologies Integrated Systems LP (L3Harris Technologies, Inc.)
• Original Assignee: L-3 Communications Integrated Systems LP (L3Harris Technologies, Inc.)
• Inventors: Stroud, Ken A.
• Primary Examiner(s): Black; Thomas G
• Assistant Examiner(s): Chen; Shelley
• Application Number:
  US11/982,436
• Publication Number:
  US 20090118875A1
• Time in Patent Office: 1,209 Days
• Field of Search: 701/3
• US Class Current: 701/3
• CPC Class Codes: G01S 2205/005 for aircraft positioning relative to other aircraft
• CPC Class Codes: G01S 5/0027 of actual mobile position, i.e. position determined on mobile
• CPC Class Codes: G05D 1/104 involving a plurality of aircrafts, e.g. formation flying traffic control systems for aircraft G08G5/00

Abstract

Systems and methods that may be employed to communicate location information between two or more aerial vehicles or other types of vehicles or other entities, and/or that may be used to facilitate coordinated operations of two or more such entities. In one example, an aerial vehicle may be kept aware of one or more location (e.g., longitude, latitude, etc.) and/or flight characteristics (e.g., altitude, directional heading, airspeed, attitude, etc.) of one or more other adjacent aerial vehicles, and each such aerial vehicle may use that location information to adjust its flight path to maintain a safe sphere of empty airspace around itself.

Claims

1. A method for coordinating operations of a group of two or more entities, said method comprising:

communicating location information derived from global positioning system (GPS) data corresponding to the geographic location of a first one of said entities of said group to at least a second one of said entities of said group by transmitting a RF signal pulse from said first entity to said second entity at a time delayed relative to a time of a provided first synchronized clock pulse, the value of said time delay being based on said location information;

determining said geographic location of said first one of said entities of said group based on said time delay value determined from said RF signal pulse received by said second one of said entities of said group; and

controlling a directional path of at least said second one of said entities of said group based at least partially on said determined geographic location of said first one of said entities of said group relative to the geographic location of said second one of said entities of said group.

2. The method of claim 1, wherein each of said entities comprises an aerial vehicle;

wherein said first synchronized clock pulse comprises a 1 pps global positioning system (GPS) signal pulse received at said first one of said aerial vehicles; and

wherein said method comprises controlling a flight path of at least said second one of said aerial vehicles of said group based at least partially on said determined geographic location of said first one of said aerial vehicles of said group relative to the geographic location of said second one of said aerial vehicles of said group.

3. The method of claim 2, further comprising:

communicating location information corresponding to the geographic location of each of said aerial vehicles of said group to each other of said aerial vehicles of said group by transmitting a RF signal pulse from each of said aerial vehicles to each other of said aerial vehicles at a time delayed relative to a time of a 1 pps GPS signal pulse received at each of said aerial vehicles, the value of said time delay of each of said transmitted RF signal pulses being based on location information corresponding to the geographic location of the aerial vehicle from which said RF signal pulse is transmitted; and

determining said geographic location of each of said aerial vehicles of said group based on said time delay value determined from said RF signal pulse received from each of said aerial vehicles of said group by each other of said entities of said group; and

controlling a flight path of each of said aerial vehicles of said group based at least partially on said determined geographic locations of each of said other aerial vehicles of said group relative to the geographic location of said aerial vehicle having a flight path being so controlled;

wherein said RF signal pulse transmitted from each of said aerial vehicles is transmitted on the same RF signal carrier frequency as said RF signal pulses transmitted from each other of said aerial vehicles.

4. The method of claim 3, wherein each of said aerial vehicles of said group is an unmanned aerial vehicle;

and wherein said method further comprises flying said group of said unmanned aerial vehicles in an autonomous manner by said step of controlling a flight path of each of said aerial vehicles of said group based at least partially on said determined geographic locations of each of said other aerial vehicles of said group.

5. The method of claim 3, further comprising using a rule-based flight coordination protocol to control a flight path of each of said aerial vehicles of said group based at least partially on said determined geographic locations of each of said other aerial vehicles of said group.

6. The method of claim 3, wherein said step of controlling comprises controlling a flight path of each of said aerial vehicles of said group to maintain a sphere of empty airspace around each of said aerial vehicles based at least partially on said determined geographic locations of each of said other aerial vehicles of said group.

7. The method of claim 2, further comprising

receiving GPS satellite signal transmissions at said first and second aerial vehicles of said group at a first time, said GPS satellite signal transmissions comprising said 1 pps GPS signal pulse;

determining said geographic location of said first one of said aerial vehicles of said group from said GPS satellite signal transmissions, said geographic location comprising a latitude value and a longitude value corresponding to said geographic location of said first one of said aerial vehicles of said group;

transmitting said RF signal pulse from said first aerial vehicle to said second aerial vehicle at a time delayed relative to a time said 1 pps GPS signal pulse is received at said first one of said aerial vehicles, the value of said time delay being based on said latitude and longitude values corresponding to said geographic location of said first one of said aerial vehicles of said group;

determining said time delay value of said RF signal pulse from said first aerial vehicle based on a time said RF signal pulse is received at said second aerial vehicle relative to a time said 1 pps GPS signal is received at said second aerial vehicle;

determining said latitude and longitude values corresponding to said geographic location of said first one of said aerial vehicles of said group based on said time delay value determined from said received RF signal pulse; and

controlling a flight path of at least said second one of said aerial vehicles of said group based at least partially on said determined latitude and longitude values corresponding to said geographic location of said first one of said aerial vehicles of said group.

8. The method of claim 2, wherein said first synchronized clock pulse comprises a first 1 pps global positioning system (GPS) signal pulse, and wherein said method further comprises:

receiving GPS satellite signal transmissions at said first aerial vehicle at a first time, said GPS satellite signal transmissions comprising said first 1 pps GPS signal pulse;

obtaining said location information by determining latitude and longitude values of a geographic location of said first aerial vehicle at said first time from said GPS satellite signal transmissions received at said first time; and

transmitting a first RF signal pulse from said first aerial vehicle at a time delayed relative to said first time that said first 1 pps GPS signal pulse is received, the value of said time delay being based on said latitude and longitude values of said determined geographic location of said first aerial vehicle at said first time.

9. The method of claim 8, further comprising:

receiving a second RF signal pulse from said second aerial vehicle at said first aerial vehicle;

determining said time delay value of said received second RF signal pulse based on a time said second RF signal pulse is received at said first aerial vehicle relative to a time said first 1 pps GPS signal is received at said first aerial vehicle;

determining said latitude and longitude values of said geographic location of said at least one second aerial vehicle at said first time based on said value of said time delay that is determined based on a time said second RF signal pulse is received at said first aerial vehicle relative to a time said first 1 pps GPS signal is received at said first aerial vehicle; and

controlling a flight path of said first aerial vehicle based at least partially on said determined latitude and longitude values of said geographic location of said second aerial vehicle at said first time relative to latitude and longitude values of said geographic location of said first aerial vehicle at said first time.

10. The method of claim 8, further comprising:

dividing or multiplying the seconds value of said latitude value of said geographic location of said first aerial vehicle at said first time by a first factor to obtain a first latitude time component, and dividing or multiplying the seconds component of said longitude value of said geographic location of said first aerial vehicle at said first time by a second factor to obtain a first longitude time component;

summing said first latitude time component and said first longitude time component together to obtain a first total time component; and

determining said time delay value by setting said time delay to be equal to said first total time component.

11. The method of claim 8, further comprising:

receiving GPS satellite signal transmissions at said first aerial vehicle at a second time later than said first time, said GPS satellite signal transmissions comprising a second 1 pps GPS signal pulse;

determining latitude and longitude values of a geographic location of said first aerial vehicle at said second time from said GPS satellite signal transmissions received at said second time; and

transmitting a second RF signal pulse from said first aerial vehicle at a time delayed relative to said second time that said second 1 pps GPS signal pulse is received, the value of said time delay being based on said latitude and longitude values of said determined geographic location of said first aerial vehicle at said second time.

12. The method of claim 11, further comprising:

receiving said second RF signal pulse from said first aerial vehicle at said second aerial vehicle;

determining said time delay value of said received second RF signal pulse based on a time said second RF signal pulse is received at said second aerial vehicle relative to a time said second 1 pps GPS signal is received at said second aerial vehicle; and

determining said latitude and longitude values of said geographic location of said first aerial vehicle at said second time based on said value of said time delay that is determined based on a time said second RF signal pulse is received from said first aerial vehicle at said second aerial vehicle relative to a time said second 1 pps GPS signal is received at said second aerial vehicle.

13. The method of claim 8, further comprising:

receiving global positioning system (GPS) satellite transmissions at said second aerial vehicle at said first time, said GPS satellite signal transmissions comprising said first 1 pps GPS signal pulse;

determining latitude and longitude values of a geographic location of said second aerial vehicle at said first time from said GPS satellite signal transmissions received at said first time;

transmitting a first RF signal pulse from said second aerial vehicle at a time delayed relative to said first time that said first 1 pps GPS signal pulse is received, the value of said time delay being based on said latitude and longitude values of said determined geographic location of said second aerial vehicle at said first time; and

transmitting said first RF signal pulse from said second aerial vehicle at the same RF signal carrier frequency that said first RF signal pulse is transmitted from said first aerial vehicle.

14. The method of claim 13, further comprising:

receiving said first RF signal pulse transmitted by said first aerial vehicle at said second aerial vehicle;

determining said time delay value of said first RF signal pulse received from said first aerial vehicle based on a time said first RF signal pulse from said first aerial vehicle is received at said second aerial vehicle relative to a time said first 1 pps GPS signal is received at said second aerial vehicle;

determining said latitude and longitude values of said geographic location of said first aerial vehicle at said first time based on said value of said time delay that is determined based on a time said first RF signal pulse from said first aerial vehicle is received at said second aerial vehicle relative to a time said first 1 pps GPS signal is received at said second aerial vehicle;

receiving said first RF signal pulse transmitted by said second aerial vehicle at said first aerial vehicle;

determining said time delay value of said first RF signal pulse received from said second aerial vehicle based on a time said first RF signal pulse from said second aerial vehicle is received at said first aerial vehicle relative to a time said first 1 pps GPS signal is received at said first aerial vehicle;

determining said latitude and longitude values of said geographic location of said second aerial vehicle at said first time based on said value of said time delay that is determined based on a time said first RF signal pulse from said second aerial vehicle is received at said first aerial vehicle relative to a time said first 1 pps GPS signal is received at said first aerial vehicle; and

controlling a flight path of said second aerial vehicle based at least partially on said determined latitude and longitude values of said geographic location of said first aerial vehicle at said first time relative to latitude and longitude values of said geographic location of said second aerial vehicle at said first time; and

controlling a flight path of said first aerial vehicle based at least partially on said determined latitude and longitude values of said geographic location of said second aerial vehicle at said first time relative to latitude and longitude values of said geographic location of said first aerial vehicle at said first time.

15. The method of claim 8, further comprising obtaining flight characteristic information of said first aerial vehicle;

and encoding said first RF signal pulse with said flight characteristic information prior to transmitting said first RF signal pulse from said first aerial vehicle.

16. A system for communicating location information, comprising:

at least one processing component coupled to a transmitter, said transmitter being configured to transmit a first RF signal pulse;

wherein said at least one processing component is configured to;

obtain first location information from global positioning system (GPS) data, said first location information comprising at least one value corresponding to a first geographic location,

determine a time delay value based on said at least one value of said location information corresponding to said first geographic location, and

provide a signal to said transmitter to cause transmission of said first RF signal pulse at a time delayed relative to a time that a first synchronized clock pulse is produced, the value of said time delay being based on said at least one value of said first location information corresponding to said first geographic location wherein said system is configured for use as a component of a first entity and wherein said system of said first entity further comprises;

a receiver coupled to said at least one processing component, said receiver being configured to receive a second RF signal pulse from at least one second entity, the second RF signal pulse being transmitted at a time delayed relative to a time that a first synchronized clock pulse is produced, the value of said time delay being based on a geographic location of said at least one second entity;

wherein said at least one processing component of said first entity is further configured to determine the geographic location of said at least one second entity based on said time delay value determined from said second RF signal pulse received by said first entity; and

wherein said at least one processing component of said first entity is further configured to control a directional path of at least said first entity based at least partially on said determined geographic location of said second entity relative to the geographic location of said first entity.

17. The system of claim 16,

wherein said at least one processing component of said first entity is further configured to:

determine a time delay value of said second RF signal pulse based on a time said second RF signal pulse is received from said second entity by said receiver of said first entity relative to a time said first synchronized clock pulse is provided; and

determine a second geographic location of said second entity based on a value of said time delay value of said second RF signal;

wherein said first and second RF signal pulses have the same RF signal carrier frequency.

18. The system of claim 16, wherein said synchronized clock pulse comprises a 1 pps global positioning system (GPS) signal pulse;

wherein said system comprises a component of a first aerial vehicle and further comprises a GPS receiver coupled to said at least one processing component;

wherein said GPS receiver is configured to receive GPS satellite signal transmissions at a first time, said GPS satellite signal transmissions comprising said first 1 pps GPS signal pulse; and

wherein said at least one processing component is configured to;

obtain said first location information by determining latitude and longitude values of a geographic location of said first aerial vehicle at said first time from said GPS satellite signal transmissions received at said first time by said GPS receiver; and

provide a signal to said transmitter to cause transmission of said first RF signal pulse from said first aerial vehicle at a time delayed relative to said first time that said first 1 pps GPS signal pulse is received, the value of said time delay being based on said latitude and longitude values of said determined geographic location of said first aerial vehicle at said first time.

19. The system of claim 18, wherein said at least one processing component is further configured to:

divide or multiply the seconds value of said latitude value of said geographic location of said first aerial vehicle at said first time by a first factor to obtain a first latitude time component, and to divide or multiply the seconds component of said longitude value of said geographic location of said first aerial vehicle at said first time by a second factor to obtain a first longitude time component;

sum said first latitude time component and said first longitude time component together to obtain a first total time component; and

determine said time delay value by setting said time delay to be equal to said first total time component.

20. The system of claim 18, further comprising:

a receiver coupled to said at least one processing component of said first aerial vehicle, said receiver being configured to receive a second RF signal pulse from at least one second aerial vehicle;

wherein said at least one processing component of said first aerial vehicle is further configured to;

determine a time delay value of said second RF signal pulse based on a time said second RF signal pulse is received by said receiver relative to said first time said first 1 pps GPS signal is received; and

determine latitude and longitude values of a geographic location of said at least one second aerial vehicle at said first time based on said value of said time delay that is determined based on a time said second RF signal pulse is received at said first aerial vehicle relative to said first time said first 1 pps GPS signal is received; and

wherein said system further comprises at least one processing component configured to provide flight control command signals to control a flight path of said first aerial vehicle based at least partially on said determined latitude and longitude values of said geographic location of said at least one second aerial vehicle at said first time relative to said latitude and longitude values of said geographic location of said first aerial vehicle at said first time.

21. The system of claim 20, wherein said at least one processing component is configured to provide flight control command signals to control a flight path of said first aerial vehicle is further configured to use a rule-based flight coordination protocol to control a flight path of said first aerial vehicle based at least partially on said determined latitude and longitude values of said geographic location of said at least one second aerial vehicle at said first time relative to said latitude and longitude values of said geographic location of said first aerial vehicle at said first time.

22. The system of claim 20, wherein said at least one processing component is configured to provide flight control command signals to control a flight path of said first aerial vehicle is further configured to control a flight path of said first aerial vehicle to maintain a sphere of empty airspace around said first aerial vehicle based at least partially on said determined latitude and longitude values of said geographic location of said at least one second aerial vehicle at said first time relative to said latitude and longitude values of said geographic location of said first aerial vehicle at said first time.

23. The system of claim 16, further comprising at least one processing component configured to obtain flight characteristic information of said first aerial vehicle and to provide a signal to said transmitter to cause transmission of said first RF signal pulse from said first aerial vehicle such that said first RF signal pulse is encoded with said flight characteristic information.

24. A method for controlling a directional path of a first entity, the method comprising:

receiving at the first entity a RF signal pulse transmitted from a second entity at a time delayed relative to a time of a provided synchronized clock pulse, the value of said time delay being based on the geographic location of the second entity;

determining said geographic location of said second entity based on said time delay value determined from said RF signal pulse received by said first entity; and

controlling a directional path of said first entity based at least partially on said determined geographic location of said second entity relative to the geographic location of said first entity.

25. A system for controlling a directional path of a first entity, comprising:

at least one processing component;

a receiver coupled to said at least one processing component, said receiver and processing component being configured for use as a component of the first entity;

where the receiver is configured to receive a RF signal pulse from at least one second entity, the second RF signal pulse being transmitted at a time delayed relative to a time that a first synchronized clock pulse is produced, the value of said time delay being based on a geographic location of said at least one second entity;

where said at least one processing component of said first entity is further configured to determine the geographic location of said at least one second entity based on said time delay value determined from said second RF signal pulse received by said first entity; and

where said at least one processing component of said first entity is further configured to control a directional path of said first entity based at least partially on said determined geographic location of said second entity relative to the geographic location of said first entity.