Integrated GPS/interference location system with anti-jam processor

• US 6,882,936 B2
• Filed: 03/03/2003
• Issued: 04/19/2005
• Est. Priority Date: 03/03/2003
• Status: Expired due to Fees

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Desjardins, Gerard A.
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): To, Tuan C
• Application Number:
  US10/376,638
• Publication Number:
  US 20040176909A1
• Time in Patent Office: 778 Days
• Field of Search: 701/213, 701/214, 342/357.06, 342/357.12, 342/357.02, 342/357.1, 342/357.15, 455/12.1, 455/456.1, 455/232.1, 455/13.14, 455/234.2, 455/3.02, 455/20, 455/427, 455/74, 455/429, 455/67.1, 455/426, 455/11.1, 455/522, 455/69, 375/346, 370/329, 370/341
• US Class Current: 701/213
• CPC Class Codes: G01S 19/21 Interference related issues ; Issues related to cross-correlation, spoofing or other methods of denial of service
• CPC Class Codes: G01S 3/46 using antennas spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems

Abstract

A user set determines a location of an interference signal by receiving a satellite signal and an interference signal and increasing the interference signal-to-noise ratio to produce a first output signal and by increasing the satellite signal-to-noise ratio to produce a second output signal.

Claims

1. A user set for facilitating the location of a first interference signal, comprising:

at least one antenna element for receiving an incoming signal wherein the incoming signal comprises at least a satellite signal and the first interference signal; and

an anti-jam processor configured to process the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal, the anti-jam processor further configured to process the incoming signal received from the at least one antenna element to increase the satellite signal-to-noise ratio thereby producing a second output signal.

2. The user set of claim 1, further comprising:

a correlation processor configured to compute a time difference of arrival and a frequency difference of arrival based on the first output signal;

a navigation processor configured to compute navigation information for the user set based on the second output signal; and

a location processor configured to compute the location of the interference signal based on the time difference of arrival, the frequency difference of arrival, and the navigation information.

3. The user set of claim 2, further comprising:

a data link to receive a first output signal and navigation information for another user set.

4. The user set of claim 1, wherein the incoming signal comprises a first interference signal and a second interference signal and wherein the anti-jam processor is configured to process the incoming signal received from the at least one antenna element to suppress the second interference signal to increase the first interference signal-to-noise ratio thereby producing the first output signal.

5. The user set of claim 1, wherein the anti-jam processor is configured to process the incoming signal received from the at least one antenna element to maximize signal power received from a predetermined direction to increase the first interference signal-to-noise ratio thereby producing the first output signal.

6. The user set of claim 5, wherein the anti-jam processor is configured to process the incoming signal received from the at least one antenna element to steer a beam in a direction of the first interference signal to increase the first interference signal to noise ratio thereby producing the first output signal.

7. The user set of claim 1, wherein the anti-jam processor is configured to process the incoming signal received from the at least one antenna element to steer a beam in a predetermined direction and minimize signal power received from other directions to increase the first interference signal-to-noise ratio thereby producing the first output signal.

8. The user set of claim 7, wherein the anti-jam processor is configured to process the incoming signal received from the at least one antenna element to steer a beam in a direction of the first interference signal and place nulls in a direction of any other interference signals received to increase the first interference signal-to-noise ratio thereby producing the first output signal.

9. The user set of claim 1, wherein the anti-jam processor is configured to process the incoming signal received from the at least one antenna element to steer a beam in a direction of the first interference signal and filter the incoming signals to pass frequencies within a bandwidth to increase the first interference signal-to-noise ratio thereby producing the first output signal, wherein the bandwidth comprises the frequencies of the first interference signal.

10. The user set of claim 1, wherein the anti-jam processor is configured to process the incoming signal received from the at least one antenna element to minimize signal power received to increase the satellite signal-to-noise ratio thereby producing a second output signal.

11. The user set of claim 1, wherein the anti-jam processor is configured to process the incoming signal received from the at least one antenna element to minimize signal power received and steer a beam in a direction of the satellite signal to increase the satellite signal-to-noise ratio thereby producing a second output signal.

12. The user set of claim 1, wherein the anti-jam processor is configured to process the incoming signal received from the at least one antenna element to steer a beam in a direction of the satellite signal to increase the satellite signal-to-noise ratio thereby producing the second output signal.

13. A method for facilitating the location of a first interference signal, comprising:

receiving an incoming signal from at least one antenna element wherein the incoming signal comprises at least a satellite signal and the first interference signal;

processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal; and

processing the incoming signal received from the at least one antenna element to increase the satellite signal-to-noise ratio thereby producing a second output signal.

14. A method according to claim 13, further comprising:

computing a time difference of arrival and a frequency difference of arrival based on the first output signal;

computing navigation information for a first user set based on the second output signal; and

computing the location of the interference signal based on the time difference of arrival, the frequency difference of arrival, and the navigation information.

15. The method according to claim 14, further comprising:

receiving a first output signal and navigation information for another user set.

16. The method according to claim 13, wherein:

the incoming signal further comprises a first interference signal and a second interference signal; and

processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises processing the incoming signals to suppress the second interference signal.

17. The method according to claim 13, wherein processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises processing the incoming signals to maximize signal power received from a predetermined direction.

18. The method according to claim 17, wherein processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises processing the incoming signals to steer a beam in a direction of the first interference signal.

19. The method according to claim 13, wherein processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises processing the incoming signals to steer a beam in a predetermined direction and minimize signal power received from other directions.

20. The method according to claim 19, wherein processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises processing the incoming signals to steer a beam in a direction of the first interference signal and place nulls in a direction of any other received interference signals.

21. The method according to claim 13, wherein processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises processing the incoming signals to steer a beam in a direction of the first interference signal and filter the incoming signals to pass frequencies within a bandwidth, wherein the bandwidth comprises the frequencies of the first interference signal.

22. The method according to claim 13, wherein processing the incoming signal received from the at least one antenna element to increase the satellite signal-to-noise ratio thereby producing a second output signal comprises processing the incoming signals to minimize signal power received.

23. The method according to claim 13, wherein processing the incoming signal received from the at least one antenna element to increase the satellite signal-to-noise ratio thereby producing a second output signal comprises processing the incoming signal to minimize signal power received and steer a beam in a direction of the satellite signal.

24. The method according to claim 13, wherein processing the incoming signal received from the at least one antenna element to increase the satellite signal-to-noise ratio thereby producing a second output signal comprises processing the incoming signals to steer a beam in a direction of the satellite signal.

25. A system for facilitating the location of a first interference signal, comprising:

means for receiving an incoming signal from at least one antenna element wherein the incoming signal comprises at least a satellite signal and the first interference signal;

means for processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal; and

means for processing the incoming signal received from the at least one antenna element to increase the satellite signal-to-noise ratio thereby producing a second output signal.

26. A system according to claim 25, further comprising:

means for computing a time difference of arrival and a frequency difference of arrival based on the first output signal;

means for computing navigation information for a first user set based on the second output signal; and

means for computing the location of the interference signal based on the time difference of arrival, the frequency difference of arrival, and the navigation information.

27. The system according to claim 26, further comprising:

means for receiving a first output signal and navigation information for another user set.

28. The system according to claim 25, wherein:

the incoming signal comprises a first interference signal and a second interference signal; and

means for processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises means for processing the incoming signals to suppress the second interference signal.

29. The system according to claim 25, wherein means for processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises means for processing the incoming signals to maximize signal power received from a predetermined direction.

30. The system according to claim 29, wherein means for processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises means for processing the incoming signals to steer a beam in a direction of the first interference signal.

31. The system according to claim 25, wherein means for processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises means for processing the incoming signals to steer a beam in a predetermined direction and minimize signal power received from other directions.

32. The system according to claim 31, wherein means for processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises means for processing the incoming signals to steer a beam in a direction of the first interference signal and place nulls in a direction of any other received interference signals.

33. The system according to claim 25, wherein means for processing the incoming signal received from the at least one antenna element to increase the first interference signal-to-noise ratio thereby producing a first output signal comprises means for processing the incoming signals to steer a beam in a direction of the first interference signal and filter the incoming signals to pass frequencies within a bandwidth, wherein the bandwidth comprises the frequencies of the first interference signal.

34. The system according to claim 25, wherein means for processing the incoming signal received from the at least one antenna element to increase the satellite signal-to-noise ratio thereby producing a second output signal comprises means for processing the incoming signals to minimize signal power received.

35. The system according to claim 25, wherein processing the incoming signal received from the at least one antenna element to increase the satellite signal-to-noise ratio thereby producing a second output signal comprises means for processing the incoming signal to minimize signal power received and steer a beam in a direction of the satellite signal.

36. The system according to claim 25, wherein means for processing the incoming signal received from the at least one antenna element to increase the satellite signal-to-noise ratio thereby producing a second output signal comprises means for processing the incoming signals to steer a beam in a direction of the satellite signal.