Accession Number : ADP006165

Title :   Hybrid PE-Ray-Mode Formulation of High Frequency Propagation in a Bilinear Tropospheric Surface Duct,

Corporate Author : NATIONAL DEFENSE ACADEMY YOKOSUKA (JAPAN)

Personal Author(s) : Ishihara, T. ; Felsen, L. B.

Report Date : SEP 1989

Pagination or Media Count : 15

Abstract : Prediction of signal strengths due to high frequency sources in the presence of a tropospheric surface or elevated duct poses a problem of substantial complexity because the propagation environment is generally heterogeneous in height as well as in the lateral domain. A prediction algorithm should not only furnish adequate accuracy but also incorporate a parametrization in terms of physical observables so that the output can be properly interpreted. Relevant physical observables include ray fields, normal (trapped) and leaky mode fields, and beam-like (parabolic) propagators. These observables are employed here in self-consistent hybrid combination to model propagation in a laterally homogeneous surface duct with bilinear refractive index profile in height. A reference solution, which has been generated by normal and leaky mode summation, is interpreted qualitatively in terms of the corresponding ray field plot. Work is in progress on a quantitative reconstruction of the reference data via the hybrid algorithm.

Descriptors :   *ELECTROMAGNETIC WAVE PROPAGATION, TROPOSPHERE, HIGH FREQUENCY, ALGORITHMS.

Subject Categories : Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE