Date of Award

12-1990

Document Type

Thesis

Degree Name

Master of Science in Electrical Engineering

Department

Department of Electrical and Computer Engineering

First Advisor

Philip Joseph, Captain, USAF

Abstract

This paper investigates the scattering from impedance strips and impedance-loaded conducting strips. The UTd diffraction coefficient for an edge in a conductor is heuristically modified for impedance edges and junctions. Essentially, this is done by scaling the UTD diffraction coefficients according to changes in the geometrical optics field. The new diffraction coefficients are then used to investigate the scattering from impedance strips and impedance- loaded conducting strips. Both uniform and tapered impedances are considered. Results are compared to moment method and physical optics predictions and to measured data. The scattering pattern of a uniform impedance strip was seen to behave as that for a conducting strip, but at a lower level. However, tapering the impedance was seen to significantly decrease the sidelobe levels relative to the main lobe. Also, applying an impedance load to a conducting strip reduced the sidelobe levels. This was most pronounced for loads of tapered impedance. the modified UTD approach accurately predicted the sidelobe levels and locations for the simple impedance strips, and worked fairly well for the impedance-loaded conducting strips. The predictions for all geometries were better near broadside incidence than near edge-on.

AFIT Designator

AFIT-GE-ENG-90D-26

DTIC Accession Number

ADA230526

Comments

The author's Vita page is omitted

Download

Share

COinS