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Title: SAR Window Functions: A Review and Analysis of the Notched Spectrum Problem

Abstract

Imaging systems such as Synthetic Aperture Radar collect band-limited data from which an image of a target scene is rendered. The band-limited nature of the data generates sidelobes, or ''spilled energy'' most evident in the neighborhood of bright point-like objects. It is generally considered desirable to minimize these sidelobes, even at the expense of some generally small increase in system bandwidth. This is accomplished by shaping the spectrum with window functions prior to inversion or transformation into an image. A window function that minimizes sidelobe energy can be constructed based on prolate spheroidal wave functions. A parametric design procedure allows doing so even with constraints on allowable increases in system bandwidth. This approach is extended to accommodate spectral notches or holes, although the guaranteed minimum sidelobe energy can be quite high in this case. Interestingly, for a fixed bandwidth, the minimum-mean-squared-error image rendering of a target scene is achieved with no windowing at all (rectangular or boxcar window).

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:
801413
Report Number(s):
SAND2002-2949
TRN: US200223%%162
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 1 Sep 2002
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; DESIGN; RADAR; WAVE FUNCTIONS; IMAGE PROCESSING

Citation Formats

DICKEY, FRED M., ROMERO, LOUIS, and DOERRY, ARMIN W. SAR Window Functions: A Review and Analysis of the Notched Spectrum Problem. United States: N. p., 2002. Web. doi:10.2172/801413.
DICKEY, FRED M., ROMERO, LOUIS, & DOERRY, ARMIN W. SAR Window Functions: A Review and Analysis of the Notched Spectrum Problem. United States. doi:10.2172/801413.
DICKEY, FRED M., ROMERO, LOUIS, and DOERRY, ARMIN W. 2002. "SAR Window Functions: A Review and Analysis of the Notched Spectrum Problem". United States. doi:10.2172/801413. https://www.osti.gov/servlets/purl/801413.
@article{osti_801413,
title = {SAR Window Functions: A Review and Analysis of the Notched Spectrum Problem},
author = {DICKEY, FRED M. and ROMERO, LOUIS and DOERRY, ARMIN W.},
abstractNote = {Imaging systems such as Synthetic Aperture Radar collect band-limited data from which an image of a target scene is rendered. The band-limited nature of the data generates sidelobes, or ''spilled energy'' most evident in the neighborhood of bright point-like objects. It is generally considered desirable to minimize these sidelobes, even at the expense of some generally small increase in system bandwidth. This is accomplished by shaping the spectrum with window functions prior to inversion or transformation into an image. A window function that minimizes sidelobe energy can be constructed based on prolate spheroidal wave functions. A parametric design procedure allows doing so even with constraints on allowable increases in system bandwidth. This approach is extended to accommodate spectral notches or holes, although the guaranteed minimum sidelobe energy can be quite high in this case. Interestingly, for a fixed bandwidth, the minimum-mean-squared-error image rendering of a target scene is achieved with no windowing at all (rectangular or boxcar window).},
doi = {10.2172/801413},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2002,
month = 9
}

Technical Report:

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