The excitation of plane surface waves

It is shown that a surface wave will be generated by a horizontal slot situated above a corrugated or dielectric-coated guiding surface. A physical interpretation of the analysis is suggested which explains the mechanism of launching in terms of a resonance phenomenon allied to that which arises when a piston attenuator is terminated by a reactance equal and opposite to its own (reactive) characteristic impedance. The problem of efficient launching is discussed, and it is shown that under suitable conditions a high launching efficiency is possible. Some of the theoretical predictions have been verified experimentally.