VLF mode conversion at terminator taking into account earth's curvature
Abstract
As an extension of earlier work in which VLF mode conversion at the solar terminator has been treated with a plane model of the earthionosphere waveguide, here a spherical model is used. This is done with some simplifications. First, the real threelayer problem (ionosphereatmosphereearth) is reduced to a boundary value problem involving fictitious surface impedances along the interfaces to the ionosphere and to the ground, chosen such that they describe in an asymptotically equivalent way the influence of these layers. Second, the thin shell approximation is employed, which permits one to reduce the problem to a quasiplane model still containing the spherical characteristics, as, for example, the characteristic values of the spherical modes. A system of coupled integral equations is obtained which is solved rigorously by an iterative procedure.
 Publication:

Radio Science
 Pub Date:
 October 1982
 DOI:
 10.1029/RS017i005p00879
 Bibcode:
 1982RaSc...17..879L
 Keywords:

 Atmospheric Models;
 Propagation Modes;
 Terminator Lines;
 Very Low Frequencies;
 Waveguides;
 Boundary Value Problems;
 Integral Equations;
 Iterative Solution