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Title: The Direction Cosine Method of Scatterer Location Extended to Spotlight-Mode IFSAR

Abstract

In this paper we have shown how the direction cosine method of stripmap-mode IFSAR maybe modified for use in the spotlight-mode case. Spotlight-mode IFSAR geometry dictates a common aperture phase center, velocity vector, and baseline vector for every pixel in an image. Angle with respect to the velocity vector is the same for every pixel in a given column and can be computed from the column index, the Doppler of the motion compensation point and the Doppler column sample spacing used in image formation. With these modifications, the direction cosines and length of the line of sight vector to every scatterer in the scene may be computed directly from the raw radar measurements of range, Doppler, and interferometric phase.

Authors:
Publication Date:
Research Org.:
Sandia National Labs., Albuquerque, NM, and Livermore, CA (US)
Sponsoring Org.:
US Department of Energy (US)
OSTI Identifier:
766558
Report Number(s):
SAND2000-1316C
TRN: AH200038%%307
DOE Contract Number:
AC04-94AL85000
Resource Type:
Conference
Resource Relation:
Conference: 34th Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, CA (US), 10/29/2000--11/01/2000; Other Information: PBD: 26 Oct 2000
Country of Publication:
United States
Language:
English
Subject:
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; APERTURES; COMPUTERS; GEOMETRY; MODIFICATIONS; RADAR; VECTORS; VELOCITY

Citation Formats

EICHEL,PAUL H. The Direction Cosine Method of Scatterer Location Extended to Spotlight-Mode IFSAR. United States: N. p., 2000. Web.
EICHEL,PAUL H. The Direction Cosine Method of Scatterer Location Extended to Spotlight-Mode IFSAR. United States.
EICHEL,PAUL H. 2000. "The Direction Cosine Method of Scatterer Location Extended to Spotlight-Mode IFSAR". United States. doi:. https://www.osti.gov/servlets/purl/766558.
@article{osti_766558,
title = {The Direction Cosine Method of Scatterer Location Extended to Spotlight-Mode IFSAR},
author = {EICHEL,PAUL H.},
abstractNote = {In this paper we have shown how the direction cosine method of stripmap-mode IFSAR maybe modified for use in the spotlight-mode case. Spotlight-mode IFSAR geometry dictates a common aperture phase center, velocity vector, and baseline vector for every pixel in an image. Angle with respect to the velocity vector is the same for every pixel in a given column and can be computed from the column index, the Doppler of the motion compensation point and the Doppler column sample spacing used in image formation. With these modifications, the direction cosines and length of the line of sight vector to every scatterer in the scene may be computed directly from the raw radar measurements of range, Doppler, and interferometric phase.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2000,
month =
}

Conference:
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  • In this paper we take a new look at the tomographic formulation of spotlight mode synthetic aperture radar (SAR), so as to include the case of targets having three-dimensional structure. This bridges the work of David C. Munson and his colleagues, who first described SAR in terms of two-dimensional tomography, with Jack Walker's original derivation of spotlight mode SAR imaging via Doppler analysis. The main result is to demonstrate that the demodulated radar return data from a spotlight mode collection represent a certain set of samples of the three-dimensional Fourier transform of the target reflectivity function, and to do somore » using tomographic principles instead of traditional Doppler arguments. We then show that the tomographic approach is useful in interpreting the two-dimensional SAR image of a three-dimensional scene. In particular, the well-known SAR imaging phenomenon commonly referred to as layover is easily explained in terms of tomographic projection. 4 refs.« less
  • In this paper we take a new look at the tomographic formulation of spotlight mode synthetic aperture radar (SAR), so as to include the case of targets having three-dimensional structure. This bridges the work of David C. Munson and his colleagues, who first described SAR in terms of two-dimensional tomography, with Jack Walker`s original derivation of spotlight mode SAR imaging via Doppler analysis. The main result is to demonstrate that the demodulated radar return data from a spotlight mode collection represent a certain set of samples of the three-dimensional Fourier transform of the target reflectivity function, and to do somore » using tomographic principles instead of traditional Doppler arguments. We then show that the tomographic approach is useful in interpreting the two-dimensional SAR image of a three-dimensional scene. In particular, the well-known SAR imaging phenomenon commonly referred to as layover is easily explained in terms of tomographic projection. 4 refs.« less
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