Delay-Doppler Radar Imaging.

Abstract

The goal of this project is to formulate and investigate new approaches for forming images of radar targets from spotlight-mode, delay-doppler measurements. These measurements could be acquired with a high-resolution radar-imaging system operating with an optical- or radio-frequency carrier. Two approaches are under study. The first is motivated by an image-reconstruction algorithm used in radionuclide imaging called the confidence-weighted algorithm; here, we will refer to this approach as the chirp-rate modulation approach. The second approach is based on more fundamental principles which starts with a mathematical model that accurately describes the physics of an imaging radar-system and then uses statistical-estimation theory with this model to derive processing algorithms; we will refer to this as the estimation-theory approach. Spotlight-mode high-resolution radar-imaging relies upon the relative motion between the transmitter, target, and receiver. The target is illuminated by a series of transmitted pulses. The return for each pulse is a superposition of reflections from various locations on the target, with each location affecting the pulse by introducing a time delay, doppler shift, and reflectance gain. The returns are processed to produce an image of the target. Two types of images are possible. One is a map in delay/doppler or range/cross-range coordinates of the target's complex-valued reflectivity, which indicates the amplitude-gain applied to the incident radar-pulse by each location on the target. The other is a map in the same coordinates of the target's scattering function, which indicates the power-gain applied at each location on the target.

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Document Details

Document Type
Technical Report
Publication Date
Nov 30, 1987
Accession Number
ADA191509

Entities

People

  • Donald L. Snyder

Organizations

  • University of Washington

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Algorithms
  • Computational Science
  • Computer Simulations
  • Data Science
  • Detectors
  • Doppler Effect
  • Electromagnetic Scattering
  • Equations
  • High Resolution
  • Information Processing
  • Information Science
  • Maximum Likelihood Estimation
  • Order Statistics
  • Radar
  • Radar Imaging
  • Statistics
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Calculus or Mathematical Analysis
  • Computer Vision.
  • Radar Systems Engineering.