Mine detection using radar vibrometer

• US 7,183,964 B2
• Filed: 08/07/2006
• Issued: 02/27/2007
• Est. Priority Date: 09/06/2002
• Status: Expired due to Fees

• Current Assignee: L-3 Communications Security & Detection Systems, Inc. (Leidos Holdings, Inc.)
• Original Assignee: L-3 Communications CyTerra Corporation (L3Harris Technologies, Inc.)
• Inventors: Steinway, William, Scott, Waymond
• Primary Examiner(s): PIHULIC, DANIEL T
• Application Number:
  US11/462,868
• Publication Number:
  US 20060267828A1
• Time in Patent Office: 204 Days
• Field of Search: 342/22, 342/27, 342/52, 342/90, 342/192, 342/194, 342/196, 367/128, 89/11.3
• US Class Current: 342/22
• CPC Class Codes: F41H 11/12 Means for clearing land minefields; Systems specially adapted for detection of landmines
• CPC Class Codes: G01S 13/32 using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
• CPC Class Codes: G01S 13/88 Radar or analogous systems specially adapted for specific applications electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00
• CPC Class Codes: G01S 13/885 for ground probing prospecting or detecting using electromagnetic waves G01V3/12
• CPC Class Codes: G01V 3/12 operating with electromagnetic waves operating with millimetre waves G01V8/005

Abstract

A frequency-stepped radar may be used to detect buried landmines by sequentially inducing vibrations of different frequencies in the landmine. A sensor detects signals associated with the vibrations, and a processor processes the signals to detect the landmine.

Claims

1. A system comprising:

a stepped-frequency radar configured to induce vibrations in a buried object using different frequencies; and

a receiver configured to;

collect, over time at a packet rate, measurement packets from electromagnetic signals associated with the vibrations, and

process the collected measurement packets to determine vibration displacement to detect the buried object.

2. The system of claim 1 wherein the receiver is configured to measure a peak of an electromagnetic signal to determine vibration displacement.

3. The system of claim 2 wherein the receiver is further configured to convert the determined vibration displacement to an audible signal.

4. The system of claim 2 wherein the receiver is further configured to identify whether the determined vibration displacement is consistent with the buried object being a landmine.

5. The system of claim 2 wherein the receiver is further configured to:

compare the determined vibration displacement with a previously determined vibration displacement; and

identify that the determined vibration displacement is consistent with the buried object being a landmine in response to a result of the comparison that exceeds a threshold difference.

6. The system of claim 1 wherein the receiver is further configured to present an audible signal when a buried object is detected.

7. The system of claim 1 wherein the measurement packets include real and imaginary values of a received electromagnetic signal.

8. The system of claim 1 wherein the receiver is further configured to apply time gates to the received measurement packets to remove clutter from a received electromagnetic signal.

9. The system of claim 1 wherein the receiver is further configured to process the received measurement packets from multiple contiguous frequencies to reduce clutter.

10. The system of claim 9 wherein the receiver is further configured to process the received measurement packets from all frequencies to reduce sparkle effects.

11. The system of claim 1 further comprising a metal detection sensor configured to detect metal.

12. A method comprising:

using a frequency-stepped radar to sequentially induce vibrations of different frequencies in a buried object; and

using a receiver to;

collect, over time at a packet rate, measurement packets from electromagnetic signals assocaited with the vibrations, and

process the collected measurement packets to determine vibration displacement to detect the buried object.

13. The method of claim 12 further comprising processing includes measuring a peak of an electromagnetic signal to determine vibration displacement.

14. The method of claim 13 further comprising converting the determined vibration displacement to an audible signal.

15. The method of claim 13 further comprising:

comparing the determined vibration displacement with a previously determined vibration displacement; and

identifying that the determined vibration displacement is consistent with the buried object being a landmine in response to a result of the comparison that exceeds a threshold difference.

16. The method of claim 12 further comprising presenting an audible signal when a buried object is detected.

17. The method of claim 12 wherein the measurement packets include real and imaginary values of a received electromagnetic signal.

18. The method of claim 12 further comprising processing the received measurement packets from all frequencies to reduce sparkle effects.

19. The method of claim 12 further comprising using a sensor to detect metal.