METHOD AND APPARATUS FOR ESTIMATING GEOLOCATIONS

• US 20080180325A1
• Filed: 01/31/2007
• Published: 07/31/2008
• Est. Priority Date: 01/31/2007
• Status: Active Grant

• Current Assignee: L-3 Communications Corporation (L3Harris Technologies, Inc.)
• Original Assignee: L-3 Communications Integrated Systems LP (L3Harris Technologies, Inc.)
• Inventors: PARKER, JOHN M., CHUNG, HYO K., LE, PHUONG H., ROBERTSON, MARK A., REID, DAVID L.
• Granted Patent: US 7,471,245 B2
• Time in Patent Office: Days
• US Class Current: 342/451
• CPC Class Codes: G01S 5/06 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/12 takes precedence

Abstract

Methods and apparatus operable to estimate the geolocation of a signal emitter. In some embodiments, the methods comprise acquiring collection data from a plurality of collector elements, computing a plurality of candidate geolocations from the acquired collection data, and applying a clustering analysis to the candidate geolocations to estimate the geolocation of the signal emitter.

Claims

1. A method of estimating a geolocation of a signal emitter, the method comprising:

acquiring collection data from a plurality of collector elements;

computing a plurality of candidate geolocations from the acquired collection data; and

applying a clustering analysis to the candidate geolocations to estimate the geolocation of the signal emitter.

2. The method of claim 1, wherein the acquired collection data includes data synchronously acquired by each collector element.

3. The method of claim 1, wherein the acquired collection data includes data acquired by each collector element at a plurality of frequencies.

4. The method of claim 3, further including forming an emitter table to categorize the acquired collection data by frequency and collector element.

5. The method of claim 1, further including applying a Cross Ambiguity Function (CAF) to the acquired data to generate a plurality of time-difference-of-arrival (TDOA) and frequency-difference-of-arrival (FDOA) pairs.

6. The method of claim 5, wherein the candidate geolocations are computed utilizing the TDOA/FDOA pairs.

7. The method of claim 1, wherein the clustering analysis is applied to the candidate geolocations to determine a cluster area and the geolocation of the signal emitter is estimated by averaging the candidate geolocations within the cluster area.

8. A method of estimating a geolocation of a signal emitter, the method comprising:

acquiring collection data from a plurality of collector elements, the acquired data including data synchronously acquired by each collector element at a plurality of frequencies;

generating a plurality of time-difference-of-arrival/frequency-difference-of-arrival (TDOA/FDOA) pairs from the acquired collection data;

computing a plurality of candidate geolocations utilizing the TDOA/FDOA pairs; and

applying a clustering analysis to the candidate geolocations to estimate the geolocation of the signal emitter.

9. The method of claim 8, further including forming an emitter table to categorize the acquired collection data by frequency and collector element.

10. The method of claim 9, further including repeatedly acquiring collection data from the collector elements and updating the emitter table after each acquisition.

11. The method of claim 8, wherein the clustering analysis is applied to the candidate geolocations to determine a cluster area and the geolocation of the signal emitter is estimated by averaging the candidate geolocations within the cluster area.

12. A computing element operable to estimate a geolocation of a signal emitter, the computing element comprising:

a memory operable to store collection data acquired from a plurality of collector elements; and

a processor coupled with the memory and operable to-compute a plurality of candidate geolocations from the acquired collection data, and

apply a clustering analysis to the candidate geolocations to estimate the geolocation of the signal emitter.

13. The computing element of claim 12, wherein the processor is further operable to apply a Cross Ambiguity Function (CAF) to the acquired data to generate a plurality of time-difference-of-arrival (TDOA) and frequency-difference-of-arrival (FDOA) pairs.

14. The computing element of claim 13, wherein the processor is operable to compute the candidate geolocations utilizing the TDOA/FDOA pairs.

15. The computing element of claim 12, wherein the processor is operable to apply the clustering analysis to the candidate geolocations to determine a cluster area and estimate the geolocation of the signal emitter by averaging the candidate geolocations within the cluster area.

16. A computer program for estimating a geolocation of a signal emitter, a least a portion of the computer program stored a computer-readable medium for operating a computing element and comprising:

a code segment operable to acquire collection data from a plurality of collector elements;

a code segment operable to compute a plurality of candidate geolocations from the acquired collection data; and

a code segment operable to apply a clustering analysis to the candidate geolocations to estimate the geolocation of the signal emitter.

17. The computer program of claim 16, wherein the acquired collection data includes data synchronously acquired by each collector element.

18. The computer program of claim 16, wherein the acquired collection data includes data acquired by each collector element at a plurality of frequencies.

19. The computer program of claim 16, further including a code segment operable to form an emitter table to categorize the acquired collection data by frequency and collector element.

20. The computer program of claim 16, further including a code segment operable to apply a Cross Ambiguity Function (CAF) to the acquired data to generate a plurality of time-difference-of-arrival (TDOA) and frequency-difference-of-arrival (FDOA) pairs.

21. The computer program of claim 20, wherein the candidate geolocations are computed utilizing the TDOA/FDOA pairs.

22. The computer program of claim 16, wherein the clustering analysis is applied to the candidate geolocations to determine a cluster area and the geolocation of the signal emitter is estimated by averaging the candidate geolocations within the cluster area.