called ground waves that carry the signal from MF AM broadcasting stations to home AM radios. The ability of surface waves to bend and follow the contour of a conductor explains why AM radio stations can be received on the far side of hills, and how over-the-horizon radar works. See also Surface wave Surface plasmon polariton Radio frequency power transmission Patents , "Surface wave transmission line". George J. E. Goubau , "Launching and receiving of surface waves". George J. E. Goubau. References Microwave technology