System and method for geo-locating and detecting source of electromagnetic emissions

Patent metadata

Field	Value
Publication number	US-9658314-B2
Application number	US-201213410586-A
Country	US
Kind code	B2
Filing date	Mar 2, 2012
Priority date	Mar 2, 2012
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

A system for identifying a real-world geographic location of an emission source emitting electromagnetic energy includes a platform configured for movement and an apparatus disposed on the platform and configured to collect and process, in a passive manner and during movement of the platform, at least a pair of successive samples of the electromagnetic energy emission and define angular and spatial coordinates of the emission source. The apparatus includes at least a pair of antennas, a receiver coupled to antennas and a processor executing a predetermined logic.

First claim

We claim:

1. A system for determining a real-world geographic location of an emission source emitting an electromagnetic energy signal, said system comprising:
(a) a platform configured for movement; and
(b) an apparatus disposed on said platform and configured to collect and process, in a passive manner and during movement of said platform, at least two pairs of successive samples of a weak electromagnetic energy signal emitted from the emission source and define, by extracting phase information from Fourier IQ data in said at least two pairs of successive samples of said weak electromagnetic energy signal through Fast Fourier Transform (FFT), angular and spatial coordinates of the emission source, one sample of said weak electromagnetic energy signal in each pair from said at least two pairs being processed, to extract said phase information, independently from but substantially simultaneously with another sample of said weak electromagnetic energy signal in said each pair from said at least two pairs.

2. The system of claim 1 , wherein said apparatus includes:
(a) a first antenna mounted on or within said platform and configured to collect at least a pair of first samples from said at least two pairs of successive samples of said weak electromagnetic energy signal;
(b) a second antenna positioned in a spaced apart relationship with said first antenna, said second antenna configured to collect at least a pair of second samples from said at least two pairs of successive samples of said weak electromagnetic energy signal;
(c) a receiver mounted on or within said platform and operatively coupled to each of said first and second antennas; and
(d) a processor operatively coupled to said receiver, said processor operable to process, during said movement of said platform, said at least two pair of said successive samples of said weak electromagnetic energy signal.

3. The system of claim 1 , wherein said weak electromagnetic energy signal is at or below −160 dBm.

4. A system for determining a real-world geographic location of a source emitting an electromagnetic energy signal, said system comprising:
(a) a platform configured for movement;
(b) means for determining position of said platform at least prior to movement thereof;
(c) at least a pair of antennas positioned in a spaced apart relationship with each other, each of said at least pair of antennas configured to collect electromagnetic energy emitted by the source, wherein at least one of said at least pair of antennas is mounted on or within said platform;
(d) a receiver mounted on or within said platform and operatively coupled to said each of said at least pair of antennas; and
(e) a processor operatively coupled to said receiver, said processor configured to process, during movement of said platform, in a parallel manner at least a pair of successive samples of a weak electromagnetic energy signal emitted from the emission source and collected independently at each of said at least pair of antennas and define, by extracting phase information, from Fourier IQ data in said electromagnetic energy signal through Fast Fourier Transform (FFT), angular and spatial coordinates of the emission source, one of said at least pair of successive samples of said weak electromagnetic energy signal being processed, to extract said phase information, independently from but substantially simultaneously with another one of said at least pair of successive samples of said weak electromagnetic energy signal.

5. The system, according to claim 4 , wherein the emission source is a stationary emission source.

6. The system, according to claim 4 , wherein the emission source is a plurality of stationary emission sources.

7. The system, according to claim 4 , wherein said electromagnetic emission is one of intentional or unintentional.

8. The system, according to claim 4 , wherein said platform is a vehicle having motive power or being connected to a vehicle having motive power.

9. The system, according to claim 4 , wherein said each of said pair of antennas is an antenna array.

10. The system, according to claim 9 , wherein said antenna array is a beam-steer antenna array.

11. The system, according to claim 4 , wherein said each of said at least pair of antennas is mounted on said platform.

12. The system, according to claim 4 , wherein said angular and spatial coordinates define a distance from said platform to the emission source.

13. The system, according to claim 4 , wherein said angular and spatial coordinates define one of an altitude of the emission source and an approach or a departure of said platform relative to the emission source.

14. A method of geo-locating an emission source emitting an electromagnetic energy signal, said method comprising the steps of:
(a) providing an apparatus including a platform configured for movement, at least a pair of antennas positioned in a spaced apart relationship with each other, each of said at least pair of antennas configured to collect the electromagnetic energy emission, wherein at least one of said at least pair of antennas is mounted on or within said platform, a receiver mounted on or within said platform and operatively coupled to said each of said at least pair of antennas, and a processor operatively coupled to said receiver;
(b) moving said apparatus toward to or away from said emission source;
(c) collecting, with each of said at least pair of antennas, at least a pair of successive samples of a weak electromagnetic energy signal emitted by said emission source;
(d) receiving, at said receiver, said at least pair of successive samples;
(e) processing, with said processor, one of said at least pair of successive samples of said weak electromagnetic energy signal, in a parallel manner, independently from but substantially simultaneously with another one of said at least pair of successive samples of said weak electromagnetic energy;
(f) extracting with said processor, in said parallel manner from Fourier IQ data through Fast Fourier Transform (FFT), phase information from said one and said another one of said at least pair of successive samples of said electromagnetic energy signal; and
(g) defining, with said processor, angular and spatial coordinates of said emission source.

15. The method, according to claim 14 , wherein said step (e) includes the step of independently decomposing wavelets from said one and said another one of said at least pair of successive samples of said weak electromagnetic energy signal.

16. The method, according to claim 14 , further including the step of combining phase information extracted in step (f) and the step of determining phase differences between said one and said another one of said at least pair of successive samples of said weak electromagnetic energy signal collected independently at said each of said at least pair of antennas.

17. The method of claim of claim 16 , further including the step of determining a travel direction of said platform.

18. The method of claim 14 , further including the step of determining at least one of a position and an orientation of said platform at least prior to movement thereof.

19. The method of claim 18 , wherein step (e) includes the step of filtering said at least one of position and orientation.

20. The method, according to claim 14 , wherein said step (g) includes the step of performing cluster analysis on phase information extracted from said one and said another one of said at least pair of successive samples of said weak electromagnetic energy

Assignees

• Parks Brandon Scott
• Keller Iii Walter J
• Hsu Jennting Timothy
• Nokomis Inc

Inventors

• Parks Brandon Scott
• Keller Iii Walter J
• Hsu Jennting Timothy

Classifications

• G01S19/24

  Acquisition or tracking {or demodulation} of signals transmitted by the system {(synchronisation aspects of direct sequence spread spectrum modulation H04B1/7073)} · CPC title

• G01S19/21

  Interference related issues {; Issues related to cross-correlation, spoofing or other methods of denial of service} · CPC title

• G01S5/0284

  Relative positioning · CPC title

• G01S5/04 Primary

  Position of source determined by a plurality of spaced direction-finders · CPC title

• G01S5/0278

  involving statistical or probabilistic considerations (G01S5/0252, G01S5/0294 take precedence) · CPC title