Firearm threat detection, classification, and location using wideband radar

• US 8,610,622 B2
• Filed: 10/25/2011
• Issued: 12/17/2013
• Est. Priority Date: 04/18/2008
• Status: Active Grant

• Current Assignee: Flex Force Enterprises Inc.
• Original Assignee: Flex Force Enterprises, LLC
• Inventors: Sullivan, Jacob Ryan, Hyman, Daniel J.
• Primary Examiner(s): Barker, Matthew M
• Application Number:
  US13/281,296
• Publication Number:
  US 20120038505A1
• Time in Patent Office: 784 Days
• Field of Search: 342/90
• US Class Current: 342/90
• CPC Class Codes: F41G 3/14 Indirect aiming means
• CPC Class Codes: F41G 3/147 based on detection of a firing weapon
• CPC Class Codes: G01S 7/412 based on a comparison between measured values and known or stored values
• CPC Class Codes: H01Q 21/205 providing an omnidirectional coverage turnstile aerials H01Q21/26

Abstract

An aimed or aiming firearm can be detected before it is able to shoot. Wideband radar signals can be used to identify the barrel of a firearm when the radar antenna and barrel are aiming at or near each other. Signal processing correlates reflected signals to the characteristics of specific firearms of interest, and alerts the user when someone is pointing such a firearm at them. Modern wideband radar systems with fast signal processing speed can enable real-time detection of firearm threats in crowded and cluttered areas before they shoot, which has never before been possible. Related systems, apparatus, methods, and articles are also described.

Claims

1. A method comprising:

transmitting radio frequency signals towards a zone of interest from a first location, the zone of interest comprising at least one weapon, the transmitted frequency signals covering a range of frequencies that are propagated down at least one type of weapon barrel;

receiving radio frequency signals reflected from the zone of interest;

comparing, by at least one programmable processor, the received radio frequency signals to a library of data characterizing a plurality of different weapons;

determining, by at least one programmable processor, based on the comparing, whether one or more weapons in the zone of interest are aimed at the first location or whether they are aimed at a different location; and

providing, by at least one programmable processor, data characterizing at least one weapon in the zone of interest based on the comparison.

2. A method as in claim 1, further comprising:

comparing, by at least one programmable processor, the received radio frequency signals to a library of radio frequency signatures for a plurality of different objects, wherein the radio frequency signatures characterize variances in phase and amplitude with both time and frequency due to radio frequency characteristics of the weapon.

3. A method as in claim 2, wherein the radio frequency signatures are derived, at least in part, empirically.

4. A method as in claim 2, wherein at least a portion of the radio frequency signatures are derived, at least in part, theoretically.

5. A method as in claim 2 further comprising:

estimating, by at least one programmable processor, a distance to the weapon; and

modifying, by at least one programmable processor, the received radio frequency signals based on a factor associated with the estimated distance;

wherein the comparing compares the modified received radio frequency signals to the radio frequency signatures for a plurality of different objects.

6. A method as in claim 2, wherein the radio frequency signatures each characterize variances in phase and amplitude with both time and frequency due to reflections associated with specific waveguide characteristics for a corresponding weapon barrel.

7. A method as in claim 2, wherein the library comprises data characterizing a fixed length of lossy transmission lines, the transmission line characterizing a steel circular waveguide of a firearm barrel and the fixed length characterizing a distance from a mouth of the firearm barrel to a chambered round.

8. A method as in claim 1, wherein the radio frequency signals are radar signals.

9. A method as in claim 1, wherein the transmitted radio frequency signals were generated with directivity greater than 10.

10. A method as in claim 1, wherein the weapon is a handheld firearm.

11. A method as in claim 10, wherein the firearm is selected from a group consisting of:

5.56 mm rifles, 7.62 mm rifles, and .50 caliber rifles.

12. A method as in claim 10, wherein the data characterizing the weapon identifies the location of the firearm.

13. A method as in claim 10, wherein the data characterizing the weapon indicates a range to the firearm.

14. A method as in claim 1, further comprising:

processing, by at least one programmable processor, the received radio frequency signals to resolve and identify reflections associated with radiating antenna characteristics of a weapon.

15. A method as in claim 1, wherein an antenna for transmitting and/or receiving the radio frequency signals has a directivity characteristic between 100 and 100,000.

16. A weapon threat detection system comprising:

an outbound antenna apparatus that transmits, from a first location, an outbound radio frequency signal toward a potential threat in a zone of interest;

an inbound antenna that receives an inbound reflected radio frequency signal from the potential threat; and

at least one processor coupled to a data store, the data store storing a library of data characterizing a plurality of different weapons;

wherein the processor is configured to analyze the inbound reflected radar signals to determine whether the potential threat includes a weapon barrel pointed in the direction of the first location or whether the potential threat includes a weapon barrel pointed at a different location by comparing the inbound reflected radio frequency signal to the library of data characterizing the plurality of different weapons.

17. A system as in claim 16, wherein the weapon barrel is part of a handheld firearm.

18. A system as in claim 16 wherein the processor initiates notification to a user of the potential threat.

19. A system as in claim 18, wherein the processor initiates notification of a user of a location of the potential threat in relation to the inbound antenna.

20. A non-transitory computer program product storing instructions, which when executed by at least one data processor of at least one computing system, result in operations comprising:

initiating transmission of radio frequency signals towards a zone of interest from a first location, the zone of interest comprising at least one weapon, the transmitted frequency signals covering a range of frequencies that are propagated down at least one type of weapon barrel;

comparing received radio frequency signals reflected from the zone of interest to a library of data characterizing a plurality of different weapons;

determining, based on the comparing, whether one or more weapons in the zone of interest are aimed at the first location or whether they are aimed at a different location; and

providing data characterizing at least one weapon in the zone of interest based on the comparison.

21. A computer program product as in claim 20, wherein the operations further comprise:

comparing the received radio frequency signals to a library of radio frequency signatures or patterns for a plurality of different objects, wherein the radio frequency signatures characterize variances in phase and amplitude with both time and frequency due to radio frequency characteristics of the weapon.

22. A computer program product as in claim 21, wherein the radio frequency signatures are derived, at least in part, empirically.

23. A system comprising:

means for transmitting radio frequency signals towards a zone of interest from a first location, the zone of interest comprising at least one weapon, the transmitted frequency signals covering a range of frequencies that are propagated down at least one type of weapon barrel;

means for receiving radio frequency signals reflected from the zone of interest;

means for comparing the received radio frequency signals to a library of data characterizing a plurality of different weapons; and

means for determining, based on the comparing, whether one or more weapons in the zone of interest are aimed at the first location or whether they are aimed at a different location; and

means providing data characterizing at least one weapon in the zone of interest based on the comparison.