Dipole
A vertical dipole is a special type of shrinkage-reducing transmission antenna for medium waves . It consists of a vertically polarized dipole , which is mounted at a precisely defined height above the earth's surface and, together with its mirror image, provides an antenna diagram with low incline radiation. A height dipole was used from 1934 to 1969 as the transmitting antenna of the Ismaning transmitter , the height dipole being on the wooden tower that was demolished in 1983.
Incidentally, a vertically polarized dipole, the dimensions of which are small compared to the suspension height, does not represent a height dipole in the actual sense, since in this case there is a spread of free space . In the case of the vertical dipole, there is a dipole whose center of gravity is slightly more than a quarter of the emitted wavelength above the ground.
literature
- Ulrich Freyer: Antenna technology for radio practitioners. 1st edition, Franzis-Verlag GmbH, Poing 2000, ISBN 3-7723-4693-6