Earth–ionosphere waveguide Earth–ionosphere waveguide The Earth–ionosphere waveguide refers to the phenomenon in which certain radio waves can propagate in the space between the ground and the boundary of the ionosphere. Because the ionosphere contains charged particles, it can behave as a conductor. The earth operates as a ground plane, and the resulting cavity behaves as a large waveguide. Extremely low frequency (ELF) (< 3 kHz) and very low frequency (VLF) (3–30 kHz) signals can propagate efficiently in this waveguide. For instance, lightning strikes launch a signal called radio atmospherics, which can travel many thousands of miles, because they are confined between the
Radio Waves (song) Radio Waves (song) "Radio Waves" is the opening track from Roger Waters' second solo studio album, "Radio K.A.O.S." It was chosen as the lead single for the album, released worldwide in May 1987. "Radio Waves" introduces the main character, Billy, a disabled man who finds a way to talk and become friends with a radio DJ. Billy is gifted and has the miracle of hearing and interpreting radio waves in his head. He explores a cordless phone which was hidden in his wheelchair by his brother Benny, after destroying and robbing a store. Recognising its similarity to a radio, he