Rick Frazier wrote:
A radiating wire is essentially an antenna. Typically, in popular use,
wires or equivalent metallic structures are not automatically considered
antennas unless they are intended to transmit or receive a specific
frequency range. This tends to increase confusion for people learning
about electromagnetic radiation.
I'd also add that I think it's important to point out to people that
quasi-static analysis leads you to regular electric and magnetic field
coupling (e.g., capacitive couplers and transformers) and that -- at least
in my opinion -- such pickup is not to be attributed to an 'antenna.' That
is, antennas are intended to transmit or receive far field radiation, even
though of course it's not like a wire can differentiate where its signal is
going to or coming from.
It's a pet peeve of mine when people talk about noise induced in systems
start calling everything in sight an 'antenna' even when there's nothing
involved that's a large fraction of the wavelength of the signals in
question... technically perhaps they're correct, but it doesn't help much
in trying to combat the problem.
---Joel Kolstad
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