An investigation of the properties of radial cylindrical surface waves launched over flat reactive surfaces

The problem of launching and supporting the radial form of surface wave over a flat surface is examined both theoretically and experimentally. The arrangement discussed consists of a vertical dipole aerial erected at different heights above the centre of a large horizontal metal plate inductively loaded at the surface, either by coating it with a thin layer of dielectric or by corrugating it with a series of concentric ridges. The earlier theoretical work of Cullen on the launching of a plane surface wave has been extended to the present case, and the results obtained have been substantially confirmed by the experimental observations recorded. In particular, the practicability of securing launching efficiencies approaching 80% for a particular height of aerial above a given surface has been fully demonstrated.