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English: Graph of the measured base feed resistance and reactance of a typical mast radiator antenna vs the height of the mast. A mast radiator antenna consists of a guyed lattice mast in which the steel mast structure itself is connected to the transmitter and functions as the antenna. It is mounted on a ceramic insulator which keeps it ...
Panel antennas are common at Ultra high frequencies or UHF, where they are often used for cellular/mobile base stations or wireless networking due to their size and directional properties. At very high frequencies, such an antenna would be impractically large for most receiving applications unless implemented as no more than a two-bay design.
The receiving antenna height of 10m dates from the 1950s when receivers were relatively insensitive and used rooftop antennas. Although this may seem unrealistic for typical situations today, when combined with the above threshold it is considered a good proxy for providing coverage to more sensitive modern receivers used without external ...
The rhombic antenna is a directional wire antenna used on MF and HF bands for shortwave reception. The antenna consists of a wire suspended above the ground in the shape of a rhombus , terminated at one end by a resistor equal the the wire's characteristic impedance, about 400 to 600 ohms, and at the other end connected to the feedline to the ...
The typical height of a 'T' antenna is shorter than the quarter wavelength required for resonance. A 'T' antenna is distinguished from the similar 'L' antenna by the place where the dangling, radiating wire attaches to the horizontal cross wire: For the 'T' antenna the dangling wire attaches to the exact center of the top horizontal wire.
VHF is the first band at which wavelengths are small enough that efficient transmitting antennas are short enough to mount on vehicles and handheld devices, a quarter wave whip antenna at VHF frequencies is 25 cm to 2.5 meter (10 inches to 8 feet) long.
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Antenna directivity is the ratio of maximum radiation intensity (power per unit surface) radiated by the antenna in the maximum direction divided by the intensity radiated by a hypothetical isotropic antenna radiating the same total power as that antenna. For example, a hypothetical antenna which had a radiated pattern of a hemisphere (1/2 ...