TECHNISCHE HOCHSCHULE GRAZ (AUSTRIA) INSTITUT FUER THEORETISCHE PHYSIK UND REAKTORPHYSIK
The present Final Report contains the continuation and extension of investigations on the propagation of electromagnetic VLF waves in polar regions. The extension considered in this report concerns mainly the terrestrial magnetic field. Part I is devoted to general theoretical considerations. It deals with the derivation of a fictitious surface impedance of the plane ionospheric boundary which mimics the influence of the ionosphere on wave propagation through the atmosphere. In Part II the surface impedance derived in Part I is applied to two waveguide models, the plane two-dimensional and the cylindrical model. In Part III the possibilities for suppressing or favouring the excitation of certain modes in the earth-ionosphere waveguide by a suitable antenna array are discussed.
Final technical rept. 1 Jan-31 Dec 74,
Continuation of contracts DAJA37-72-C-3796 and DAJA37-71-C-3546. See also report dated Dec 73, AD-775 477.