Resolution and synthetic aperture characterization of sparse radar arrays

• Published in: IEEE transactions on aerospace and electronic systems Vol. 39; no. 3; pp. 921 - 935
• Main Authors: Goodman, N.A., Stiles, J.M.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.07.2003; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Air traffic control; Ambiguity; Arrays; Filtering; History; Matched filters; Pattern matching; Radar; Radar satellites; Radar signal processing; Satellite constellations; Signal analysis; Signal design; Spaceborne radar; Synthetic aperture radar; Synthetic apertures
• ISSN: 0018-9251; 1557-9603
• DOI: 10.1109/TAES.2003.1238746

The concept of radar satellite constellations, or clusters, for synthetic aperture radar (SAR), moving target indicator (MTI), and other radar modes has been proposed and is currently under research. These constellations form an array that is sparsely populated and irregularly spaced; therefore, traditional matched filtering is inadequate for dealing with the constellation's radiation pattern. To aid in the design, analysis, and signal processing of radar satellite constellations and sparse arrays in general, the characterization of the resolution and ambiguity functions of such systems is investigated. We project the radar's received phase history versus five sensor parameters: time, frequency, and three-dimensional position, into a phase history in terms of two eigensensors that can be interpreted as the dimensions of a two-dimensional synthetic aperture. Then, the synthetic aperture expression is used to derive resolution and the ambiguity function. Simulations are presented to verify the theory.