Radar Imaging of Buildings Using Model-Based Focusing and Data-Based Focusing

• US 20090207067A1
• Filed: 02/12/2009
• Published: 08/20/2009
• Est. Priority Date: 02/14/2008
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Samaniego, Raymond, Birleson, Stanley V.
• Granted Patent: US 7,898,468 B2
• Time in Patent Office: Days
• US Class Current: 342/22
• CPC Class Codes: G01S 13/56 for presence detection presence detection using near field arrangements G01V3/00, e.g. G01V3/08, G01V3/12; burglar, theft or intruder alarms with electrical actuation G08B13/22 - G08B13/26
• CPC Class Codes: G01S 13/888 through wall detection
• CPC Class Codes: G01S 13/90 using synthetic aperture techniques , e.g. synthetic aperture radar [SAR] techniques

Abstract

According to one embodiment, an image generating device includes an image former coupled to a radar that transmits and receives electro-magnetic radiation at multiple frequencies. The image former generates an image using information received from the radar, adjusts the image according to a material characteristic of the object, and combines the image with other images received at differing frequencies to form a resulting image.

Claims

1. An image generating device comprising:

an image former comprising a computer-readable media storing code executable by a computer processor of a computing system, the computing system coupled to a radar that is operable to transmit and receive electro-magnetic radiation at a plurality of frequencies in the range of 500 Mega-Hertz to 3 Giga-Hertz, the image former operable, at each of the plurality of frequencies, to;

receive, from the radar, the electro-magnetic radiation reflected from a building;

generate an image of the building from the received electro-magnetic radiation;

adjust the image according to a material characteristic of a wall of the building, the material characteristic comprising a thickness of the wall and a dielectric constant of a material in which the wall is made;

apply a phase gradient factor to a plurality of contiguous regions of the image, the plurality of the contiguous regions overlapping one another, the phase gradient factor comprising a phase difference of the received electro-magnetic radiation between adjacent samples of each of the plurality of contiguous regions; and

combine the image with other images received from the radar at the differing plurality of frequencies to form a resulting image.

2. An image generating device comprising:

an image former comprising a computer-readable media storing code executable by a computer processor of a computing system, the image former operable, at each of the plurality of frequencies, to;

receive, from a radar, the electro-magnetic radiation reflected from an object;

generate an image of the object from the received electro-magnetic radiation;

adjust the image according to a material characteristic of the object; and

combine the image with other images received from the radar at the differing plurality of frequencies to form a resulting image.

3. The image generating device of claim 2, wherein the image former is operable to apply a phase gradient factor to a contiguous region of the image, the phase gradient factor comprising a phase difference of the received electro-magnetic radiation between adjacent samples of the contiguous region.

4. The image generating device of claim 3, wherein the image former is further operable to apply the phase gradient factor to a plurality of the contiguous regions of the image, the plurality of the contiguous regions overlapping one another.

5. The image generating device of claim 2, wherein the object is a building having a wall and the material characteristic comprises a thickness of the wall and a dielectric constant of a material in which the wall is made.

6. The image generating device of claim 2, wherein the image former is operable to adjust the image using a material characteristic that is manually determined.

7. The image generating device of claim 2, wherein the image former is operable to adjust the image using a material characteristic that is determined using an automated artificial intelligence process.

8. The image generating device of claim 2, wherein the image former is operable to adjust the image using a material characteristic that is heuristically determined.

9. The image generating device of claim 2, wherein the radar is a synthetic aperture radar.

10. The image generating device of claim 2, wherein the radar is operable to transmit and receive electro-magnetic radiation at a plurality of frequencies in the range of 500 Mega-Hertz to 3 Giga-Hertz.

11. An image generating method comprising:

generating, by a radar, electro-magnetic radiation that is transmitted toward an object at a plurality of frequencies;

receiving reflected electro-magnetic radiation from an object;

generating an image of the object from the received electro-magnetic radiation;

adjusting the image according to a material characteristic of the object; and

combining the image with other images received from the radar at the differing plurality of frequencies to form a resulting image.

12. The method of claim 11, further comprising applying a phase gradient factor to a contiguous region of the image, the phase gradient factor comprising a phase difference of the received electro-magnetic radiation between adjacent samples of the contiguous region.

13. The method of claim 12, further comprising applying a phase gradient factor to a plurality of the contiguous regions of the image, the plurality of the contiguous regions overlapping one another.

14. The method of claim 11, wherein generating the image of the object comprises generating the image of a building having a wall and the material characteristic comprises a thickness of the wall and a dielectric constant of a material in which the wall is made.

15. The method of claim 11, further comprising manually determining the material characteristic of the object.

16. The method of claim 11, further comprising determining the material characteristic using an automated artificial intelligence process.

17. The method of claim 11, further comprising heuristically determining the material characteristic of the object.

18. The method of claim 11, wherein generating the electro-magnetic radiation by the radar comprises generating the electro-magnetic radiation by a synthetic aperture radar.

19. The method of claim 11, wherein generating the electro-magnetic radiation at a plurality of frequencies comprises generating the electro-magnetic radiation at a plurality of frequencies in the range of 500 Mega-Hertz to 3 Giga-Hertz.