Search results
Results From The WOW.Com Content Network
In telecommunications, the effective height of an antenna is the height of the antenna's center of radiation above the ground. In low-frequency applications involving loaded or nonloaded vertical antennas, the effective height is the moment of the current distribution in the vertical section, divided by the input current. For an antenna with a ...
Height above average terrain (HAAT), or (less popularly) effective height above average terrain (EHAAT), is the vertical position of an antenna site above the surrounding landscape. HAAT is used extensively in FM radio and television , as it is more important than effective radiated power (ERP) in determining the range of broadcasts ( VHF and ...
The Friis transmission formula is used in telecommunications engineering, equating the power at the terminals of a receive antenna as the product of power density of the incident wave and the effective aperture of the receiving antenna under idealized conditions given another antenna some distance away transmitting a known amount of power. [1]
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 ...
h is the height of the antenna, λ is the wavelength, and I 0 is the RMS input current in amperes. This formula shows that the radiated power depends on the product of the base current and the effective height, and is used to determine how many metre-amps are required to achieve a given amount of radiated power.
It can be used for base-station antenna heights ranging from 30–1000 m. Okumura developed a set of curves giving the median attenuation relative to free space (A mu), in an urban area over a quasi-smooth terrain with a base station effective antenna height (hte) of 200 m and a mobile antenna height (hre) of 3 m. These curves were developed ...
Die WOW!-Bewerbung 4 Inhalt Inhalt Die Autorin 6 Das Unternehmen 7 Vorwort 8 1 Einleitung10 2 Der WOW!-Effekt 11 2.1 Total Recall 11 2.2 Wann es WOW! macht 12
The effective area of an antenna is defined as "In a given direction, the ratio of the available power at the terminals of a receiving antenna to the power flux density of a plane wave incident on the antenna from that direction, the wave being polarization matched to the antenna."