Richard Harrison wrote:
Tom Donaly, KA6RUH wrote:
"I know there are people in the past who have attempted to characterize
antennas as transmission lines."
True. You can include Terman among them.
Terman discusses antenna current distribution on page 866 of his 1955
edition:
"Under most circumstances the losses are sufficiently low and the ratio
of wire length to diameter sufficiently great so that to a first
approximation the current distribution can be taken as that for a line
with zero losses; it then has the characteristics discussed in Sec,
4-5."
Sec.4-5 is found on page 95 and is titled: "The Effect of Attenuation on
Voltage and Current Distribution - Lossless Lines".
Sec. 4-5 is in Terman`s chapter on Transmission lines. Obviously an
open-circuit antenna has the same current distribution as an
open-circuit transmission line, and for the same reason.
Best regards, Richard Harrison, KB5WZI
You don't even have to go as far back as Terman. Reg Edwards bases his
antenna programs on the transmission line behavior of antennas, and
his programs do as well as you'd want. That's one way to look at
antenna behavior. It's not the only way, and it doesn't mean that
Cecil knows what he's talking about when he espouses the theories
he made up in his head out there in the hot Texas sun.
73,
Tom Donaly, KA6RUH
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