Abstract
An approximate theory of ELF propagation in the Earth-ionosphere transmission line is developed by combining the reflection theory of Booker and Lefeuvre (1977) with Greifinger and Greiferinger's (1978, 1979) treatment of the effect of ionization below the level of reflection. The theory allows for the influence of the Earth's magnetic field, for reflection from the gradient on the underside of the D region (or, at night, of a ledge below the E region), for reflection from the gradient on the underside of the E region, and for reflection from the gradient on the topside of the E region. The procedure is to compare local vertical gradient with local wavelength, thereby classifying altitude into intervals where the gradient is high and ones where it is low. Where the gradient is low, the phase-integral treatment is adequate. An interval where the gradient is high may, to a first approximation, be replaced by a discontinuity. The amount of the discontinuity is the difference between the refractive indices at the top and bottom of the interval of high gradient, judged in relation to local wavelength. It is then a matter of combining reflections from the several discontinuities. This requires calculation of the complex phase-changes between the discontinuities. But these are the intervals where the phase-integral treatment is available. To a beter approximation, there is a non-zero phase-change associated with an interval of high gradient. The method for incorporating this is described.
Similar content being viewed by others
References
Bannister, P. R. et al.: 1979, Extremely Low Frequency (ELF) Propagation, Naval Underwater Systems Center, New London, Connecticut.
Barr, R.: 1971, J. Atmos. Terr. Phys. 33, 1577.
Barr, R.: 1975a, J. Atmos. Terr. Phys. 37, 1405.
Barr, R.: 1975b, Int. J. Electronics 34, 241.
Behroozi-Toosi, A. B. and Booker, H. G.: 1983, Space Sci. Rev. 35, 91 (this issue).
Booker, H. G.: 1936, Proc. Roy. Soc. London A155, 235.
Booker, H. G.: 1975, Phil. Trans. Roy. Soc. London A280, 57.
Booker, H. G. and Lefeuvre, F.: 1977, J. Atmos. Terr. Phys. 39, 1277.
Budden, K. G.: 1952, Proc. Roy. Soc. London A215, 215.
Budden, K. G.: 1961a, Radio Waves in the Ionosphere, Cambridge University Press, Cambridge.
Budden, K. G.: 1961b, The Wave-Guide Mode Theory of Wave Propagation, Logos Press, London.
Galejs, J.: 1972, Terrestrial Propagation of Long Electromagnetic Waves, Pergamon Press, Oxford.
Greifinger, C. and Greifinger, P.: 1978, Radio Science 13, 831.
Greifinger, C. and Greifinger, P.: 1979, Radio Science 14, 889.
Hayes, M. G. W.: 1971, Proc. Roy. Soc. London A324, 369.
Wait, J. R.: 1962, Electromagnetic Waves in Stratified Media, MacMillan, New York.
Wait, J. R.: 1974, IEEE Trans. Commun. 22, 353.
Author information
Authors and Affiliations
Additional information
Reprinted from J. Atmos. Terr. Phys. 42.
Supported by the Office of Naval Research under Contract N00014-78-C-0682.
Rights and permissions
About this article
Cite this article
Booker, H.G. A simplified theory of ELF propagation in the Earth-ionosphere transmission line. Space Sci Rev 35, 9–31 (1983). https://doi.org/10.1007/BF00173689
Issue Date:
DOI: https://doi.org/10.1007/BF00173689