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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Measurements of ocean surface waves using synthetic aperture radar

Assal, Hany Mohamed. January 1981 (has links)
Thesis (Ph. D.)--Stanford University, 1981. / Includes bibliographical references (leaves [88]-91).
52

Adaptive multiscale estimation for fusing image data

Slatton, Kenneth Clinton. January 2001 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI Company.
53

Array processing methods for calibrating Inverse Synthetic Aperture Radar and Multiple Pass Synthetic Aperture Radar

She, Zhishun. January 2000 (has links) (PDF)
Table of corrections inserted opposite table of contents. Bibliography: p.191-212. Investigates calibration for errors of a synthetic aperture in Inverse Synthetic Aperture Radar and Multiple Pass Synthetic Aperture Radar. Both are reviewed as the problems of array processing and are solved from the point of array calibration.
54

Sea state monitoring by radar altimeter from a microsatellite

Sun, Yiping January 2001 (has links)
This thesis constitutes a general survey and a study of significant extensions to the usual conventional satellite radar altimetry. Historically radar altimeter has been configured to the measurement of mean sea level. It is well known that other statistics such as Significant Wave Height (SWH) and wind speed are in principle recoverable from the radar echo and these are currently of great interest. It has been the aim in this thesis to optimize such measurements, for a general meteorological application, with less interest shown in absolute measurement of sea level. Current technology makes possible a total Earth survey using a constellation of small satellites, covering the entire Earth sea surface with short revisit time. Such solutions necessitate less cost, lower power, and less precise attitude control than the scientific satellites used hitherto. The purpose of this thesis is to present a novel two mode radar altimeter for sea state monitoring. SWH is still measured by conventional high-resolution mode, which is not sensitive to off-nadir pointing. An additional novel low-resolution mode is proposed for wind speed measurement. By using this mode, wind speed measurement is much more robust to pointing error than by using conventional high-resolution mode. An improved wind speed measurement can be achieved by using a cost effective small satellite. Some considerable time was also spent on incorporating SAR (Synthetic Aperture Radar) into altimetry techniques to improve the signal to noise ratio. For sea state monitoring the improvements are relatively disappointing, although greater improvement are expected for ice sheet monitoring.
55

Infrared aperture synthesis imaging of close binary stars with the Iota.

Kraus, Stefan 01 January 2003 (has links) (PDF)
No description available.
56

Multichannel synthetic aperture radar

Rosenberg, Luke January 2007 (has links)
"In this thesis, the two problems of image formation for a Multichannel Synthetic Aperture Radar (MSAR) and suppressing interferences while forming a good quality image have been addressed. For the first problem, three wavefront reconstruction algorithms were presneted based on the multichannel Matched Filter (MF) imagining equation which demonstrated differing levels of performance and accuracy. A fourth algorithm known as multichannel backprojection was also presented to provide comparative quality with a reduced computational load. To address the second problem, a detailed jammer model was described and tested with a multichannel imaging algorithm to demonstrate the effect of hot-clutter on a SAR image. Multi-channel imaging and optimal slow-time Space Time Adaptive Processing (STAP) were shown to only partially suppress the hot-clutter interference, while optimal fast-time STAP demonstrated a much greater performance." --p. 185 of source document. / Thesis (Ph.D.)--School of Electrical and Electronic Engineering, 2007.
57

Ionospheric effects on synthetic aperture radar imaging /

Liu, Jun, January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 100-105).
58

Fast circular aperture synthesis in sar all-aspect target imaging

Burki, Jehanzeb 14 October 2008 (has links)
The objective of this research is a fast circular synthetic aperture radar (F-CSAR) algorithm. Slow-time imaging distinguishes synthetic aperture radar (SAR) from its predecessor imaging radars. SAR slow-time imaging is strongly rooted in Huygens-Fresnel principle and Kirchhoff's approximation based scalar diffraction theory. Slant-plane SAR Green's function and resultant Fourier integral, unlike some Fourier integrals, cannot be analyzed using residue theory from complex analysis and Cauchy-Riemann equations yield analyticity. The asymptotic expansion of 1D and 2D Fourier integrals renders a decomposition of the Green's function leading to SAR data focusing. The research unveils Fraunhofer diffraction patterns in 2D aperture synthesis formulation corresponding to various aperture shapes including circular aperture that appears to be an optimum aperture shape from the mathematical condition in the asymptotic expansion. It is shown that these diffraction patterns may be used for refocusing of defocused images. F-CSAR algorithm is demonstrated using Householder transform recently shown to have improved error bounds and stability. Research is also carried out into various interpolation schemes. Backprojection implementation of CSAR is compared to F-CSAR and elevation coverage renders 3D reconstruction. F-CSAR is also demonstrated using GTRI T-72 tank turntable data.
59

Synthetic Aperture LADAR Automatic Target Recognizer Design and Performance Prediction via Geometric Properties of Targets

Ross, Jacob W. 13 June 2022 (has links)
No description available.
60

Effect of Atmospheric Turbulence on Synthetic Aperture Ladar Imaging Performance

Schumm, Bryce Eric 20 December 2017 (has links)
No description available.

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