Dismount step discrimination with temporal adaptive matched filtering of doppler spectral features

• US 8,102,310 B2
• Filed: 03/31/2009
• Issued: 01/24/2012
• Est. Priority Date: 03/31/2009
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Krikorian, Kapriel, Rosen, Robert, Krikorian, Mary
• Primary Examiner(s): Brainard, Timothy A
• Application Number:
  US12/416,098
• Publication Number:
  US 20100245159A1
• Time in Patent Office: 1,029 Days
• Field of Search: 342/90, 342/160, 342/162, 342/192, 342/195
• US Class Current: 342/195
• CPC Class Codes: G01S 7/415 Identification of targets based on measurements of movement associated with the target

Abstract

A process for detecting and discriminating a particular target, such as an ambulating human, amidst an environment crowded with other objects or humans having similar doppler profiles to the desired target. A method according to one embodiment includes generating an initial radar image corresponding to a received doppler profile of a target, and generating a matched filter signal corresponding to the received doppler profile. The matched filter signal is correlated with subsequently received radar images to detect and discriminate the target.

Claims

1. A method comprising:

generating an initial radar image corresponding to a received doppler profile of a target measured over a plurality of coherent processing intervals;

smoothing the initial radar image in doppler or time over the plurality of coherent processing intervals;

generating a matched filter corresponding to the smoothed initial radar image;

generating a matched filter signal from the matched filter;

generating a subsequent radar image; and

correlating the matched filter signal with the subsequent radar image to discriminate the target.

2. The method of claim 1, further comprising:

generating a second matched filter corresponding to a stored doppler profile of an intended target;

generating a second matched filter signal from the second matched filter; and

correlating the second matched filter signal with the subsequent radar image to discriminate the target.

3. A method comprising:

generating an initial radar image corresponding to a received doppler profile of a target;

generating a matched filter signal corresponding to the received doppler profile of the target;

generating a subsequent radar image; and

correlating the matched filter signal with the subsequent radar image to discriminate the target,

wherein generating the initial radar image comprises;

receiving and storing information corresponding to a doppler profile of radiation scattered off the target over a plurality of coherent arrays; and

smoothing the information to reduce variations in the information in doppler or time.

4. The method of claim 3, wherein smoothing the information comprises smoothing out variations in the information in doppler.

5. The method of claim 3, wherein smoothing the information comprises calculating a time average of the doppler profile over a plurality of intervals.

6. The method of claim 5, wherein the target is a dismount, and the plurality of intervals comprise a plurality of steps by the dismount.

7. The method of claim 3, wherein generating the matched filter signal comprises generating voltages generally matching the smoothed information in doppler and time.

8. The method of claim 7, further comprising varying a stretch factor of the matched filter, the stretch factor corresponding to a stretching in doppler or in time of the smoothed information.