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Old November 24th 05, 08:49 PM posted to rec.radio.amateur.antenna
Tim Wescott
 
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Default Antenna reception theory

Paul Taylor wrote:
Hi,

I am looking for an explanation of how an antenna receives a signal due
to the E-field of an electromagnetic wave.

I have looked in some books, and can understand transmission, but the
books I have looked in don't explain reception.

I have found an explanation of how the H-field induces a signal in a loop
antenna: a changing magnetic flux will induce a current.

But what about the E-field and a dipole antenna? I guess that the E-field
causes electrons to move in the antenna wire, because in a solid
conductor, electrons will move until the E-field inside the solid is
cancelled out?

I have googled but having difficulty finding a good explanation. Any
pointers?

Thanks & regards,

Paul.

Transmission and reception work essentially the same way -- if an
antenna induces a certain field pattern in space, then that same field
pattern will induce the same voltages going the other way.

Most books spend about that much space telling you about the principal,
then use the rest of the time telling you how antennas transmit, leaving
it to you to figure out how they receive.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com