skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: High Resolution Terrain Elevation Mapping Results from Airborne Cross-Track SAR Stereo

Abstract

No abstract prepared.

Authors:
; ;
Publication Date:
Research Org.:
Sandia National Labs., Albuquerque, NM (US); Sandia National Labs., Livermore, CA (US)
Sponsoring Org.:
US Department of Energy (US)
OSTI Identifier:
769072
Report Number(s):
SAND2000-3005C
TRN: AH200108%%34
DOE Contract Number:
AC04-94AL85000
Resource Type:
Conference
Resource Relation:
Conference: IEEE ICASSP 2001 Conference, Salt Lake City, UT (US), 05/07/2001--05/11/2001; Other Information: PBD: 1 Dec 2000
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; SPATIAL RESOLUTION; MAPPING; RADAR; AERIAL SURVEYING; COMPLEX TERRAIN; LEVELS; PERFORMANCE

Citation Formats

Jakowatz, C.V. Jr., Yocky, D.A., and Wahl, D.E.. High Resolution Terrain Elevation Mapping Results from Airborne Cross-Track SAR Stereo. United States: N. p., 2000. Web.
Jakowatz, C.V. Jr., Yocky, D.A., & Wahl, D.E.. High Resolution Terrain Elevation Mapping Results from Airborne Cross-Track SAR Stereo. United States.
Jakowatz, C.V. Jr., Yocky, D.A., and Wahl, D.E.. Fri . "High Resolution Terrain Elevation Mapping Results from Airborne Cross-Track SAR Stereo". United States. doi:. https://www.osti.gov/servlets/purl/769072.
@article{osti_769072,
title = {High Resolution Terrain Elevation Mapping Results from Airborne Cross-Track SAR Stereo},
author = {Jakowatz, C.V. Jr. and Yocky, D.A. and Wahl, D.E.},
abstractNote = {No abstract prepared.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Dec 01 00:00:00 EST 2000},
month = {Fri Dec 01 00:00:00 EST 2000}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share:
  • No abstract prepared.
  • 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
  • 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
  • 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
  • Coherent stereo pairs from cross-track synthetic aperture radar (SAR) collects allow fully automated correlation matching using magnitude and phase data. Yet, automated feature matching (correspondence) becomes more difficult when imaging rugged terrain utilizing large stereo crossing angle geometries because high-relief features can undergo significant spatial distortions. These distortions sometimes cause traditional, shift-only correlation matching to fail. This paper presents a possible solution addressing this difficulty. Changing the complex correlation maximization search from shift-only to shift-and-scaling using the downhill simplex method results in higher correlation. This is shown on eight coherent spotlight-mode cross-track stereo pairs with stereo crossing angles averaging 93.7{supmore » o} collected over terrain with slopes greater than 20{sup o}. The resulting digital elevation maps (DEMs) are compared to ground truth. Using the shift-scaling correlation approach to calculate disparity, height errors decrease and the number of reliable DEM posts increase.« less