Accession Number : AD0429755

Title :   PERIODIC STRUCTURES ON CURVED SURFACES,

Corporate Author : WASHINGTON UNIV SEATTLE COLL OF ENGINEERING

Personal Author(s) : Lean,Eric Gung-Hwa ; Ishimaru,Akira

Report Date : OCT 1963

Pagination or Media Count : 27

Abstract : An extension is presented of the theory developed for plane periodic structures to cylindrical structures having an azimuthal periodicity. The main object is obtaining k - v diagrams (where v is the complex azimuthal propagation constant). Since the cylindrical structures considered have azimuthal periodicity, the fields can be expanded, in accordance with Floquet's theorem, in space harmonics. Two particular structures are considered: (a) the curved corrugated surface and (b) the curved periodic slotted conductors. For (a) the characteristic equation for v is obtained by equating appropriate energies on the surface of the structure; for (b), the characteristic equation is obtained by using the transverse resonance condition. An approximate solution for v is found for structure (a). In this case, a perturbation technique permits obtaining the real and imaginary part of the azimuthal propagation constant for the slow region and for the n equals minus 1 leaky wave region. (Author)

Descriptors :   (*CURVED PROFILES, PERIODIC VARIATIONS), CYLINDRICAL BODIES, HEMISPHERICAL SHELLS, MECHANICAL WAVES, PROPAGATION, PERTURBATION THEORY, HARMONIC ANALYSIS

Distribution Statement : APPROVED FOR PUBLIC RELEASE