Cage aerial
（重定向自Cage antenna）
A Cage aerial is a radio antenna, which consists of the top portion of a tower or mast and of several parallel wires, which are radially arranged around the lower part of the mast. one advantage of the cage aerial is that the supporting tower can be grounded, allowing it to be used for other radio services, such as a support for VHF or UHF antennas. A grounded tower also simplifies the installation of aircraft warning lamps. Cage aerials have been built in different variants for broadcasting stations in the longwave and mediumwave band.