No abstract

The ohlique reflection of VLF rad io waves from a cont inuously stratifi ed ionized medium is considered. The profile of the eff ecti\'e conductiv ity is taken to be of an eXIlonrntlal form. This is a fair represe ntation for the actual D layer of the lOnosphere. It IS 8howI1 that the g radi ent of the conductivity change has a mar ked effect on the reflection characteristics.

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 .

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Th e obli que refl ection of radio waves from a continuously stratified ionized medium is cons id ered . In this p ap er t he m ed iu m is assumed to be isotrop ic. T he h eight profile of the effect ive cond uctivity is a Gaussian curve superimposed on th e (u nd istu rbed ) exponentia l form. The refl ection coefficient is shown to be influenced by the vertical location of the Ga uss ian perturbation . In some cases the magnitude of the reflection coefficient is increased while, in other situations, it is d ecrea cd. In nearly all cases, insofa r as p hase is concerned, t he pre ence of t he p ert ur bation correspon ds to a lowering of the refl ection h eig ht .