RE: NEC-LIST:Proper Antenna Patterns

>You are somewhat correct. Because an antenna has it own characteristic
>impedance, the current distribution on the antenna is altered by the
>"source" impedance whether it is a receive or transmit antenna. Altering the
>current distribution in turn alters the pattern. This may not be noticeable
>on a simple dipole but becomes quit noticeable in complex scattering
>environments (even on simple Yagis).
>
>-----Original Message-----
>From: ROSSI Giuseppe [mailto:giuseppe.rossi_at_fiat.com]
>Sent: Thursday, October 11, 2001 9:08 AM
>To: 'KLysiak'
>Subject: R: NEC-LIST:Proper Antenna Patterns
>
>
>altough I'm not a pure scientist on antenna
>as an engineer, i believe that antenna pattern do not depend on
>antenna input impedance.
>The radiation pattern is completely due to the flow of the current on the
>antenna.
>So as long as there is current flowing on the antenna i.e.
>the input impedance is not completely reactive every antenna produces
>its own antenna pattern.
>
>In other word the field emitted by the antenna do not rely on input
>impedance
>but only on the current and geometrical property of the antenna
>
>Sincerely
>
>Ing. Giuseppe Rossi

I believe Mr./Dr. Rossi is correct. I've never encountered a
situation in which the antenna pattern is altered by a passive
terminating impedance. Of course the impedance at a given frequency
seen at the terminals (feedpoint) of an antenna depends upon antenna
geometry and the environment (any nearby metallic or dielectric
structures). Sincerely,

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