Control of Electromagnetic Scattering from Wing Profiles by Impedance Loading


Book Description

A computational technique has been developed to calculate the electromagnetic scattering from two-dimensional wing profiles loaded by impedance strips. These strips are represented by impedance boundary conditions. This report deals with the parallel electric polarization (TM polarization) while a similar study of the perpendicular polarization is contained in Reference (1). The effect of the impedance loading is studied for different shapes and sizes of the wing, and for different angles of incidence. The last part of the report deals with the relation between two- and three-dimensional scattering. Three-dimensional problems may in certain cases be solved at least approximately from the knowledge of the scattered field in two-dimensional problems. (Author).




Continuation of the Investigation of Multi-frequency Radar Reflectivity and Radar Target Identification


Book Description

This report summarizes research during the period July 1, 1974 to June 30, 1975 under the contract on two technical objectives of the Air Force: improved detection and discrimination of radar targets and reduction of nonspecular scattering by wing geometries. The report is contained in two main sections. The first section outlines methods for deducing the complex natural resonances of arbitrary radar targets and the use of these resonances via predictor-correlator processing for detection and discrimination. Illustrative examples of both natural resonance extraction and discrimination are given for aircraft targets. The second section of the report summarizes the analysis of a loaded two-dimensional wind model for horizontal polarization. Hybrid techniques combining moment methods and the geometrical theory of diffraction are used and the loading consists of surface impedance patches. Examples of reduction of the nonspecular cross section are given. A 'folded dipole' like antenna is used as an alternate mechanism for controlling edge diffracted fields.










Radio Science


Book Description




Government Reports Annual Index


Book Description

Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.




R & D Abstracts


Book Description