Launching a surface wave over the Earth

Proposals are made for a ferrite-loaded horn type of antenna capable of launching a 1.5 MHz surface wave over the Earth. The use of a ferrite coating on the conductor laid parallel with the ground, and forming one side of the horn, makes provision for a surface reactance which can be tapered up to reduce the size of the radiating aperture, and thence tapered down again to match the reactance of the ground.