Effect of earth's rotation and range foldover on space-based radar performance

Unnikrishna Pillai, Braham Himed, Ke Yong Li

Research output: Contribution to journalArticle

Abstract

Space-based radar (SBR) by virtue of its motion generates a Doppler frequency component to the clutter return from any point on the Earth as a function of the SBR-Earth geometry. The effect of the rotation of the Earth around its own axis also adds an additional component to this Doppler frequency. The overall effect of the rotation of the Earth on the Doppler turns out to be two correction factors in terms of a crab angle affecting the azimuth angle, and a crab magnitude scaling the Doppler magnitude of the clutter patch. Interestingly, both these quantities depend only on the SBR orbit inclination and its latitude and not on the location of the clutter patch of interest. Further, the crab angle has maximum effect for an SBR on a polar orbit that is above the equator. The crab magnitude, on the other hand, peaks for an SBR on an equatorial orbit. Together with the range foldover phenomenon, their overall effect is to generate Doppler spread/splitting resulting in wider clutter notches that degrade the clutter nulling performance of adaptive processing techniques. A detailed performance analysis and methods to minimize these effects are discussed here.

Original languageEnglish (US)
Pages (from-to)917-931
Number of pages15
JournalIEEE Transactions on Aerospace and Electronic Systems
Volume42
Issue number3
DOIs
StatePublished - 2006

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Earth (planet)
Orbits
Space-based radar
Geometry
Processing

ASJC Scopus subject areas

  • Aerospace Engineering
  • Electrical and Electronic Engineering
  • Computer Networks and Communications

Cite this

Effect of earth's rotation and range foldover on space-based radar performance. / Pillai, Unnikrishna; Himed, Braham; Li, Ke Yong.

In: IEEE Transactions on Aerospace and Electronic Systems, Vol. 42, No. 3, 2006, p. 917-931.

Research output: Contribution to journalArticle

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