Radio frequency power transmission is the transmission of the output power of a

transmitter In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the ...

to an

antenna Antenna ( antennas or antennae) may refer to: Science and engineering * Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g., TV or radio) waves * Antennae Galaxies, the name of two collid ...

. When the antenna is not situated close to the transmitter, special

transmission line In electrical engineering, a transmission line is a specialized cable or other structure designed to conduct electromagnetic waves in a contained manner. The term applies when the conductors are long enough that the wave nature of the transmi ...

s are required. The most common type of transmission line for this purpose is large-diameter

coaxial cable Coaxial cable, or coax (pronounced ) is a type of electrical cable consisting of an inner conductor surrounded by a concentric conducting shield, with the two separated by a dielectric ( insulating material); many coaxial cables also have a p ...

. At high-power transmitters, cage lines are used. Cage lines are a kind of overhead line similar in construction to coaxial cables. The interior conductor is held by insulators mounted on a circular device in the middle. On the circular device, there are wires for the other pole of the line. Cage lines are used at high-power transmitters in Europe, like longwave transmitter Topolna,

longwave-transmitter Solec Kujawski The Longwave transmitter Solec Kujawski is a longwave broadcasting facility of the Polish Radio for the AM-LW (long wave) 225 kHz frequency/1333 meters wavelength. Its construction was necessary after the collapse of the Warsaw radio mast ...

and some other high-power transmitters for long-, medium- and shortwave. For UHF and VHF,

Goubau line A Goubau line or Sommerfeld–Goubau line, or G-line for short, is a single-wire transmission line used to conduct radio waves at UHF and microwave frequencies. The dielectric coated transmission line was invented by F. Harms cited i Stulle, Ber ...

s are sometimes used. They consist of an insulated single wire mounted on insulators. On a Goubau line, the wave travels as longitudinal currents surrounded by transverse EM fields. For

microwave Microwave is a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter corresponding to frequencies between 300 MHz and 300 GHz respectively. Different sources define different frequency ra ...

waveguide A waveguide is a structure that guides waves, such as electromagnetic waves or sound, with minimal loss of energy by restricting the transmission of energy to one direction. Without the physical constraint of a waveguide, wave intensities de ...

s are used.

External links

Cage lines of Solec Kujawski transmitter

Cage lines of longwave transmitter Topolna(second image)(third image)
{{Telecommunications Cables Power cables Radio technology