A UTD (Uniform Geometrical Theory of Diffraction) Scattering Analysis of Pyramidal Absorber for Design of Compact Range Chambers
Abstract
The compact range allows for the measurement of radar cross section and antenna patterns in a relatively small room. An offset-feed parabolic reflector is normally used to approximate a plane wave in the target zone; however, some of the energy transmitted by the feed will strike the ceiling, walls, and floor of the room. These stray signals then scatter in all directions. To reduce the level of scattered energy, the room is typically lined with pyramidal-shaped radar absorbing material. However, the behavior of this material is not well understood. A diffraction formulation, based on the Uniform Geometrical Theory of Diffraction is developed for a lossy dielectric corner. Using this formulation, a computer code is written that calculates the bistatic scattering from a pyramidal absorber tip. Sample results display some features of scattering from a single pyramid. Calculations are then compared with backscatter measurements of a single pyramid, and with bistatic measurements of an absorber wall. Next, a general purpose computer code is written which calculates the scattering into the target zone of a compact range from the pyramidal absorber which lines the room. Sample calculations show the total power scattered into the target zone, and how strongly various locations in the room contribute to this total scattered power. Theses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1988
- Accession Number
- ADA199219
Entities
People
- Philip J. Joseph
Organizations
- Air Force Institute of Technology