Utilizing Near-Field Measurements to Characterize Far-Field Radar Signatures

Abstract

The increased need for stealth aircraft requires an on-site Far-Field (FF) Radar Cross-Section (RCS) measurement process. Conducting these measurements in on-site Near-Field (NF) monostatic facilities results in significant savings for manufacturers and acquisition programs. However, NF measurements are not directly extended to a FF RCS. Therefore, a large target Near-Field to Far-Field Transformation (NFFFT) is needed for RCS measurements. One approach requires an Inverse Synthetic Aperture Radar (ISAR) process to create accurate scattering maps. The focus of this work is the development of accurate NF scattering maps generated by a monostatic ISAR process. As a first look, the process is isolated to a simulated environment to avoid the uncontrollable effects of real measurement environments. The simulation begins with a NF Synthetic Target Generator (STG) which approximates a target using scattering centers illuminated by spherical electromagnetic waves to approximating NF scattering. The resulting NF In-phase and Quadrature (IQ) data is used in a "Trapezoidal" ISAR process to create spatially distorted images that are accurately corrected within the ISAR process resolution using a newly developed NF correction. The resulting spatially accurate ISAR images do not complete the NFFFT. However, accurate scattering maps are essential for process development.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 2004
Accession Number
ADA426468

Entities

People

  • John R. Watkins

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Aircrafts
  • Carrier Frequencies
  • Continuous Waves
  • Detection
  • Doppler Effect
  • Electric Fields
  • Electrical Engineering
  • Electromagnetic Fields
  • Far Field
  • Radar Signals
  • Radiation Patterns
  • Signal Processing
  • Synthetic Aperture Radar
  • Target Recognition
  • Three Dimensional
  • Wave Propagation

Fields of Study

  • Physics

Readers

  • Computer Vision.
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Rocket Propulsion.