System and Method for Allocating Jamming Energy Based on Three-Dimensional Geolocation of Emitters

• US 20120309288A1
• Filed: 05/31/2011
• Published: 12/06/2012
• Est. Priority Date: 05/31/2011
• Status: Active Grant

• Current Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Original Assignee: ITT Manufacturing Enterprises, Inc. (ITT, Inc.)
• Inventors: Lu, Ning Hsing
• Granted Patent: US 8,615,190 B2
• Time in Patent Office: Days
• US Class Current: 455/1
• CPC Class Codes: H04K 2203/34 involving multiple cooperating jammers
• CPC Class Codes: H04K 3/45 characterized by including monitoring of the target or target signal, e.g. in reactive jammers or follower jammers for example by means of an alternation of jamming phases and monitoring phases, called "look-through mode"

Abstract

According to an embodiment of the present invention jamming energy is allocated to a plurality of emitters based on a three-dimensional (3-D) emitter geolocation technique that determines the geolocation of radio frequency (RF) emitters based on energy or received signal strength (RSS) and/or time differences of arrival (TDOAs) of transmitted signals. The three-dimensional (3-D) emitter geolocations are used to rank emitters of interest according to distance and available radio frequency (RF) jamming energy is allocated to the emitters in rank order. The techniques may be employed with small unmanned air vehicles (UAV), and obtains efficient use of jamming energy when applied to radio frequency (RF) emitters of interest.

Claims

1. A system for locating an emitter and transmitting jamming signals at said emitter within an area comprising:

a receiver to receive signals transmitted by said emitter and obtain measurements of said received signals at a plurality of different locations within said area;

a processor to process said measurements to locate said emitter within said area, wherein said processor includes;

a location module to process said measurements and determine a three-dimensional location of said emitter within said area based on relationships of distances between said emitter and each of said plurality of locations, wherein said measurements are proportional to said distances; and

a transmitter to transmit said jamming signals at said emitter based on said three-dimensional location of said emitter within said area.

2. The system of claim 1, wherein said location module includes:

a variable module to determine said three-dimensional location by solving a set of simultaneous equations relating to said distances, wherein said set of simultaneous equations include unknown variables representing coordinates of said three-dimensional location of said emitter within said area.

3. The system of claim 2, wherein said measurements include energy measurements of said signals transmitted by said emitter based on a received signal strength of said signals transmitted by said emitter.

4. The system of claim 2, wherein said measurements include time difference of arrival measurements of said signals transmitted by said emitter based on reception times of said signals transmitted by said emitter, said reception time differences of arrival being proportional to said distances.

5. The system of claim 1, wherein said receiver receives signals transmitted by a plurality of emitters and obtains measurements of said received signals at said plurality of different locations within said area and said location module processes said measurements and determines three-dimensional locations of said plurality of emitters within said area, and wherein said processor further includes:

an emitter analysis module to;

determine an emitter type associated with each emitter; and

rank said plurality of emitters based on said emitter type and said three-dimensional locations of said plurality of emitters within said area, and wherein said transmitter transmits jamming signals at said plurality of emitters based on said rank.

6. The system of claim 5, wherein said emitter analysis module includes:

a correlation module to identify an emitter of interest by geo-spatially correlating said three-dimensional locations of said plurality of emitters within said area with known information for said area.

7. The system of claim 5, wherein said emitter analysis module includes:

a tracking module to generate tracking data for said plurality of emitters based on said three-dimensional locations of said plurality of emitters within said area.

8. The system of claim 7, wherein said emitter analysis module includes:

a situational awareness module to generate situational awareness data for said area based on said tracking data.

9. The system of claim 8, further comprising:

a transceiver to transmit and receive situational awareness data to or from another platform; and

wherein said situational awareness module combines situational awareness data for said area with situational awareness data for an area associated with said other platform to produce combined situational awareness data.

10. The system of claim 9, wherein said situational awareness module includes:

an emitter allocation module to allocate emitters, subject to said jamming signals, between said system and said other platform based on said combined situational awareness data.

11. The system of claim 5, wherein said emitter analysis module includes:

an energy allocation module to allocate jamming signal energy for transmission at each of said plurality of emitters.

12. The system of claim 11, wherein said energy allocation module is configured to allocate sufficient jamming signal energy for transmission at successive emitters in rank order until transmission energy is exhausted.

13. The system of claim 5, further comprising:

a plurality of antennas; and

wherein said emitter analysis module includes;

an antenna switching module to select one or more antennas for transmitting said jamming signals at each of said plurality of emitters based antenna characteristics of each of said plurality of antennas.

14. The system of claim 5, wherein said emitter analysis module includes:

a spectrum analysis module to determine a frequency band associated with each of said plurality of emitters; and

said system further comprises;

a jamming subsystem selection module configured to select one or more jamming subsystems based on said frequency bands;

a first jamming subsystem, wherein said transmitter is part of said first jamming subsystem for transmitting jamming signals within a first frequency band; and

a second jamming subsystem for transmitting jamming signals within a second frequency band.

29. The system of claim 1, wherein said measurements include energy measurements of said signals transmitted by said emitter based on a received signal strength of said signals transmitted by said emitter and said measurements include time difference of arrival measurements of said signals transmitted by said emitter based on reception times of said signals transmitted by said emitter, said reception time differences of arrival being proportional to said distances, and wherein said location module processes said measurements and determines a three-dimensional location of said emitter within said area based on said energy measurements and said time difference of arrival measurements.

15. A method for locating an emitter and transmitting jamming signals at said emitter within an area comprising:

(a) receiving signals transmitted by said emitter via a receiver and obtaining measurements of said received signals at a plurality of different locations within said area;

(b) processing said measurements, via a processor, and determining a three-dimensional location of said emitter within said area based on relationships of distances between said emitter and each of said plurality of locations, wherein said measurements are proportional to said distances; and

(c) transmitting said jamming signals at said emitter based on said three-dimensional location of said emitter within said area.

16. The method of claim 15, wherein step (b) further includes:

(b.1) determining said three-dimensional location by solving a set of simultaneous equations relating to said distances, wherein said set of simultaneous equations includes unknown variables representing coordinates of said three-dimensional location of said emitter within said area.

17. The method of claim 16, wherein said measurements include energy measurements of said signals transmitted by said emitter based on a received signal strength of said signals transmitted by said emitter.

18. The method of claim 16, wherein said measurements include time difference of arrival measurements of said signals transmitted by said emitter based on reception times of said signals transmitted by said emitter, said reception time differences of arrival being proportional to said distances.

19. The method of claim 15, wherein step (a) comprises receiving signals transmitted by a plurality of emitters and obtaining comprises obtaining measurements of said received signals at said plurality of different locations within said area, wherein step (b) further includes:

(b.1) processing said measurements and determining three-dimensional locations of said plurality of emitters within said area

(b.2) determining an emitter type associated with each emitter; and

(b.3) ranking said plurality of emitters based on said emitter type and said three-dimensional locations of said plurality of emitters within said area, and wherein said transmitter transmits jamming signals at said plurality of emitters based on said rank.

20. The method of claim 19, wherein step (b) further includes:

(b.4) identifying any of said plurality of emitters as an emitter of interest by geo-spatially correlating said three-dimensional locations of said plurality of emitters within said area with known information for said area.

21. The method of claim 19, wherein step (b) further includes:

(b.5) generating tracking data for said plurality of emitters based on said three-dimensional locations of said plurality of emitters within said area.

22. The method of claim 21, wherein step (b) further includes:

(b.6) generating situational awareness data for said area based on said tracking data.

23. The method of claim 22, further comprising:

(d) transmitting or receiving situational awareness data to or from another platform; and

wherein step (b) further includes;

(b.7) combining situational awareness data for said area with situational awareness data for an area associated with said other platform to produce combined situational awareness data.

24. The method of claim 23, wherein step (b) further includes:

(b.8) allocating emitters subject to jamming between platforms based on said combined situational awareness data.

25. The method of claim 19, wherein step (b) further includes:

(b.4) allocating jamming signal energy for transmission at each of said plurality of emitters.

26. The method of claim 25, wherein allocating jamming signal energy comprises allocating sufficient jamming signal energy for transmission at successive emitters in rank order until transmission energy is exhausted.

27. The method of claim 19, wherein step (b) further includes:

(b.3) selecting one or more antennas from a plurality of antennas for transmitting said jamming signals at each of said plurality of emitters based antenna characteristics of each of said plurality of antennas.

28. The method of claim 19, wherein step (b) further includes:

(b.4) analyzing the spectrum of said received signals to determine a frequency band associated with each of said plurality of emitters; and

(b.5) selecting one or more jamming subsystems based on said frequency bands associated with each of said plurality of emitters.

30. The method of claim 15, wherein said measurements include energy measurements of said signals transmitted by said emitter based on a received signal strength of said signals transmitted by said emitter and said measurements include time difference of arrival measurements of said signals transmitted by said emitter based on reception times of said signals transmitted by said emitter, said reception time differences of arrival being proportional to said distances, and wherein step (b) further includes:

(b.1) processing said measurements and determining three-dimensional locations of said emitter within said area based on said energy measurements and said time difference of arrival measurements.