On the theory of reflection of low- and very-low-radiofrequency waves from the ionosphere

Abstract

The rigo ro us appli cation of t he magn eto-ionic t heory to t he calculation of re flection coeffi cients for a sha rpl y bound ed ionospher e mod el is carri ed ou t . The p ap er is illu str ated with compu tations applicable to the D-region or t he E-region of t he ionosp her e. The quasilongi t udinal approxim ation is d eriv ed from this t heory a nd the r a nge of validi ty of this a pproximatio n is illustra ted . The r estri ctions imposed by t he use of a s ha rply bounded mod el ionospher e a re discussed .

Electron density profiles in the lower ionosphere deduced from long path VLF wave propagation

“…The transmission of VLF radio waves over long distances is best described by waveguide mode theory. There is a large number of very elaborate theoretical investigations in this field of mode propagation [e.g., Budden, 1961;Galejs, 1968Galejs, , 1969Johler and Walters, 1960;Pappert et al, 1967;Wait, 1962]. Thus propagation conditions of each excited mode are defined by the electrical properties of the earth's surface and the reflection coefficient of the lower ionosphere.…”

A General Analytic Solution for Reflection From a Sharply Bounded Anisotropic Ionosphere

“…Solutions to the reflection coefficient matrix for a sharply bounded, anisotropic ionosphere are given in the literature for a number of special cases. In addition, the general case was solved by Johler and Walters (1960). However, their solution is not in closed form and requires fairly complicated techniques for solving_.…”

Wave hop theory of long distance propagation of low-frequency radio waves

“…If the r eceiYer and/or trn,n smittel' are elevated, the integrand of I j is multiplied by G,_Y, (klr)G. _y, (kl b), where N ow, the effect of the earth's magnetic field is consider ed. Assuming that o~ = 0, and t he ionospher e is locally plan ar, (26) where (27) The planar anisotropic ionospheric reflection coefficients Tee, T em, Tme, and T mm [Johler and Walters, 1960] correspond to IIR II , IIR J.., J..R II , and J.. RJ.., respectiYely, in the notation of Wait [1962] and others. Explicit expressions [or the T's are given by Johler and Berry [1964].…”