“…There are two basic approaches taken to solve the problem of the coupling of the radiation from a ionospheric source into the Earth-ionosphere waveguide. One approach centers around matching the fields radiated by an elementary dipole source in the ionosphere to the Earth-ionosphere waveguide modal fields [Einaudi and Wait, 1971;Tripathi et al, 1982;Pappert, 1973;Chang et al, 1982;Bellyustin et al, 1975]. The other approach involves the use of reciprocity [Galejs, 1971;Barr and Stubbe, 1984a, b].…”