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Title: Terrain elevation mapping results from airborne spotlight-mode coherent cross-track SAR stereo.

Abstract

No abstract prepared.

Authors:
; ;  [1];
  1. (.,
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
913528
Report Number(s):
SAND2003-0313J
TRN: US200802%%691
DOE Contract Number:
AC04-94AL85000
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proposed for publication in IEEE Trans. on Geoscience and Remote Sensing.
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; OPTICAL RADAR; PERFORMANCE; COMPLEX TERRAIN; LEVELS; MAPPING; REMOTE SENSING

Citation Formats

Yocky, David Alan, Wahl, Daniel Eugene, Jakowatz, Charles V., Jr., and .). Terrain elevation mapping results from airborne spotlight-mode coherent cross-track SAR stereo.. United States: N. p., 2003. Web.
Yocky, David Alan, Wahl, Daniel Eugene, Jakowatz, Charles V., Jr., & .). Terrain elevation mapping results from airborne spotlight-mode coherent cross-track SAR stereo.. United States.
Yocky, David Alan, Wahl, Daniel Eugene, Jakowatz, Charles V., Jr., and .). Wed . "Terrain elevation mapping results from airborne spotlight-mode coherent cross-track SAR stereo.". United States. doi:.
@article{osti_913528,
title = {Terrain elevation mapping results from airborne spotlight-mode coherent cross-track SAR stereo.},
author = {Yocky, David Alan and Wahl, Daniel Eugene and Jakowatz, Charles V., Jr. and .)},
abstractNote = {No abstract prepared.},
doi = {},
journal = {Proposed for publication in IEEE Trans. on Geoscience and Remote Sensing.},
number = ,
volume = ,
place = {United States},
year = {Wed Jan 01 00:00:00 EST 2003},
month = {Wed Jan 01 00:00:00 EST 2003}
}
  • No abstract prepared.
  • In this report, we employ an approach quite different from any previous work; we show that a new methodology leads to a simpler and clearer understanding of the fundamental principles of SAR interferometry. This methodology also allows implementation of an important collection mode that has not been demonstrated to date. Specifically, we introduce the following six new concepts for the processing of interferometric SAR (INSAR) data: (1) processing using spotlight mode SAR imaging (allowing ultra-high resolution), as opposed to conventional strip-mapping techniques; (2) derivation of the collection geometry constraints required to avoid decorrelation effects in two-pass INSAR; (3) derivation ofmore » maximum likelihood estimators for phase difference and the change parameter employed in interferometric change detection (ICD); (4) processing for the two-pass case wherein the platform ground tracks make a large crossing angle; (5) a robust least-squares method for two-dimensional phase unwrapping formulated as a solution to Poisson`s equation, instead of using traditional path-following techniques; and (6) the existence of a simple linear scale factor that relates phase differences between two SAR images to terrain height. We show both theoretical analysis, as well as numerous examples that employ real SAR collections to demonstrate the innovations listed above.« less
  • In this paper we describe a new method for creating three-dimensional images using pairs of synthetic aperture radar (SAR) images obtained from a unique collection geometry. This collection mode involves synthetic apertures that have a common center. In this sense the illumination directions for the two SAR images are the same, while the slant planes are at different spatial orientations. The slant plane orientations give rise to cross-range layover (fore-shortening) components in the two images that are of equal magnitude but opposite directions. This differential cross-range layover is therefore proportional to the elevation of a given target, which is completelymore » analogous to the situation in stereo optical imaging, wherein two film planes (corresponding to the two slant planes) result in elevation-dependent parallax. Because the two SAR collections are coherent in this particular collection mode, the images have the same speckle patterns throughout. As a result, the images may be placed into stereo correspondence via calculation of correlations between micro-patches of the complex image data. The resulting computed digital stereo elevation map can be quite accurate. Alternatively, an analog anaglyph can be displayed for 3-D viewing, avoiding the necessity of the stereo correspondence calculation.« less
  • For synthetic aperture radar systems, missing data samples can cause severe image distortion. When multiple, coherent data collections exist and the missing data samples do not overlap between collections, there exists the possibility of replacing data samples between collections. For airborne radar, the known and unknown motion of the aircraft prevents direct data sample replacement to repair image features. Finally, this paper presents a method to calculate the necessary phase corrections to enable data sample replacement using only the collected radar data.
  • All prior interferometric SAR imaging experiments to date dealt with pairwise processing. Simultaneous image collections from two antenna systems or two-pass single antenna collections are processed as interferometric pairs to extract corresponding pixel by pixel phase differences which encode terrain elevation height. The phase differences are wrapped values which must be unwrapped and scaled to yield terrain height. We propose two major classes of techniques that hold promise for robust multibaseline (multiple pair) interferometric SAR terrain elevation mapping. The first builds on the capability of a recently published method for robust weighted and unweighted least-squares phase unwrapping, while the secondmore » attacks the problem directly in a maximum likelihood (ML) formulation. We will provide several examples (actual and simulated SAR imagery) that illustrate the advantages and disadvantages of each method.« less