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Old May 30th 07, 07:15 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
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Default Determining Total Gain of an Antenna

Richard Harrison wrote:
If the questioner draws his information from Terman and Kraus, he won`t
err.


Don't forget Balanis who said: "Standing wave antennas,
such as the dipole, can be analyzed as traveling wave
antennas with waves propagating in opposite directions
(forward and backward) ..."

To answer the original questioner: Consider the forward
and backward traveling waves separately and phasor add
the two voltages or two currents to obtain the net
voltage or net current. For an ordinary dipole, the
forward voltage and forward current amplitudes decline
by ~5% during the forward trip from the feedpoint to the
tip of the antenna. There they are reflected and suffer
another ~5% decline on their way back to the feedpoint.
The feedpoint impedance is a result of the superposition
of the forward and reflected waves on the standing-wave
antenna.
--
73, Cecil http://www.w5dxp.com