The electric acreage backbone at a specific point can be bent from the ability delivered to the transmitting antenna, its geometry and radiation resistance. Consider the case of a center-fed half-wave dipole antenna in chargeless amplitude (). If complete from attenuate conductors, the accepted administration is about sinusoidal and the beaming electric acreage is accustomed by
Current administration on antenna of breadth according to one bisected amicableness ().
where is the bend amid the antenna arbor and the agent to the ascertainment point, is the aiguille accepted at the feed-point, is the permittivity of free-space, is the acceleration of ablaze in a vacuum, and is the ambit to the antenna in meters. When the antenna is beheld battery () the electric acreage is best and accustomed by
Solving this blueprint for the aiguille accepted yields
The boilerplate ability to the antenna is
where is the center-fed half-wave antenna’s radiation resistance. Substituting the blueprint for into the one for and analytic for the best electric acreage yields
Therefore, if the boilerplate ability to a half-wave dipole antenna is 1 mW, again the best electric acreage at 313 m (1027 ft) is 1 mV/m (60 dBµ).
For a abbreviate dipole () the accepted administration is about triangular. In this case, the electric acreage and radiation attrition are
Using a action agnate to that above, the best electric acreage for a center-fed abbreviate dipole is
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