Method for Determining the Geographic Coordinates of Pixels in SAR Images

• US 20120133550A1
• Filed: 06/16/2010
• Published: 05/31/2012
• Est. Priority Date: 06/25/2009
• Status: Active Grant

• Current Assignee: Airbus Defence and Space GmbH
• Original Assignee: EADS Deutschland GmbH (Airbus SE)
• Inventors: Benninghofen, Benjamin, Koban, Tamer, Stahl, Christoph
• Granted Patent: US 9,927,513 B2
• Time in Patent Office: Days
• US Class Current: 342/25.A
• CPC Class Codes: G01S 13/90 using synthetic aperture techniques , e.g. synthetic aperture radar [SAR] techniques
• CPC Class Codes: G01S 7/295 Means for transforming co-ordinates or for evaluating data, e.g. using computers
• CPC Class Codes: G09B 29/10 Map spot or coordinate position indicators; Map reading aids optical projection apparatus per se G03B

Abstract

A method for effecting the airborne determination of geographic coordinates of corresponding pixels from digital synthetic aperture radar images, where the SAR images are available in the form of slant range images and the recording position of the respective SAR image is known. The coordinates of the corresponding pixels in the SAR images and the corresponding range gates are used in each case to determine the distance between a corresponding resolution cell on the ground and the respective recording position of the respective SAR image. The determined distances and associated recording positions of the SAR images are used to determine the geographic coordinates of the corresponding pixels in the SAR images by employing a WGS84 ellipsoid.

Claims

1-4. -4. (canceled)

5. A method for airborne determination of geographic coordinates of corresponding pixels from digital synthetic aperture radar images, wherein the SAR images are available in a form of slant range images and a recording position of the respective SAR image is known, the method comprising:

determining a distance between a corresponding resolution cell on a ground and the respective recording position of the respective SAR image using coordinates of the corresponding pixels in the SAR images and corresponding range gates; and

determining, by using the determined distances and associated recording positions of the SAR images, the geographic coordinates of the corresponding pixels in the SAR images by employing a WGS84 ellipsoid.

6. The method according to claim 5, wherein a mean altitude of a target region that is predefined for an SAR image is used to determine the geographic coordinates of corresponding pixels.

7. The method according to claim 5, wherein a relief map that is predefined for an SAR image is used to determine the geographic coordinates of corresponding pixels.

8. The method according to claim 5, wherein two or three SAR images are used to determine the geographic coordinates of corresponding pixels from digital synthetic aperture radar images.