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Title: Bandwidth requirements for fine resolution squinted SAR

Abstract

The conventional rule-of-thumb for Synthetic Aperture Radar is that an RF bandwidth of c/(2{rho}{sub r}) is required to image a scene at the desired slant-range resolution {rho}{sub r}, and perhaps a little more to account for window functions and sidelobe control. This formulation is based on the notion that the total bandwidth required is the same bandwidth that is required for a single pulse. What is neglected is that efficient processing of an entire synthetic aperture of pulses will often require different frequency content for each of the different pulses that makeup a synthetic aperture. Consequently, the total RF bandwidth required of a Synthetic Aperture Radar may then be substantially wider than the bandwidth of any single pulse. The actual RF bandwidth required depends strongly on flight geometry, owing to the desire for a radar to maintain a constant projection of the Fourier space collection surface onto the {omega}{sub y} axis. Long apertures required for fine azimuth resolution, and severe squint angles with steep depression angles may require total RF bandwidths well beyond the minimum bandwidth required of any single transmitted pulse, perhaps even by a factor of two or more. Accounting for this is crucial to designing efficient versatilemore » high-performance imaging radars. This paper addresses how a data set conducive to efficient processing might increase the total RF bandwidth, and presents examples of how a fixed RF bandwidth might then limit SAR geometries.« less

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:
752099
Report Number(s):
SAND99-2360C
TRN: AH200018%%441
DOE Contract Number:
AC04-94AL85000
Resource Type:
Conference
Resource Relation:
Conference: SPIE 14th Annual International Symposium on Aerospace/Defense Sensing, Simulation and Control, Orlando, FL (US), 04/24/2000--04/28/2000; Other Information: PBD: 1 Mar 2000
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; RADAR; IMAGES; GEOMETRY; MOTION; CORRECTIONS; WAVE FORMS; SPECIFICATIONS; SAR; BANDWIDTH; SQUINT; MOTION COMPENSATION

Citation Formats

DOERRY,ARMIN W. Bandwidth requirements for fine resolution squinted SAR. United States: N. p., 2000. Web.
DOERRY,ARMIN W. Bandwidth requirements for fine resolution squinted SAR. United States.
DOERRY,ARMIN W. 2000. "Bandwidth requirements for fine resolution squinted SAR". United States. doi:. https://www.osti.gov/servlets/purl/752099.
@article{osti_752099,
title = {Bandwidth requirements for fine resolution squinted SAR},
author = {DOERRY,ARMIN W.},
abstractNote = {The conventional rule-of-thumb for Synthetic Aperture Radar is that an RF bandwidth of c/(2{rho}{sub r}) is required to image a scene at the desired slant-range resolution {rho}{sub r}, and perhaps a little more to account for window functions and sidelobe control. This formulation is based on the notion that the total bandwidth required is the same bandwidth that is required for a single pulse. What is neglected is that efficient processing of an entire synthetic aperture of pulses will often require different frequency content for each of the different pulses that makeup a synthetic aperture. Consequently, the total RF bandwidth required of a Synthetic Aperture Radar may then be substantially wider than the bandwidth of any single pulse. The actual RF bandwidth required depends strongly on flight geometry, owing to the desire for a radar to maintain a constant projection of the Fourier space collection surface onto the {omega}{sub y} axis. Long apertures required for fine azimuth resolution, and severe squint angles with steep depression angles may require total RF bandwidths well beyond the minimum bandwidth required of any single transmitted pulse, perhaps even by a factor of two or more. Accounting for this is crucial to designing efficient versatile high-performance imaging radars. This paper addresses how a data set conducive to efficient processing might increase the total RF bandwidth, and presents examples of how a fixed RF bandwidth might then limit SAR geometries.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2000,
month = 3
}

Conference:
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