Re: NEC-List: Q: Current distribution

Hi Robert,

  Thanks. I am much worried about the concept that I have used. Can I
write the current distribution in in form?

        I = Iosin[k(l-z')],0<=z'<=L

where L is the length of the wire,
      Io is the max amplitude of the current.

[NB: the wire antenna is oriented on the z-axis and parallel to it.]

  By doing so, I get the far-field pattern similar to that given by
MiniNEC base on the assumption that the wire antenna is in the
free-space and there is no load attached to it. I wonder is this
concept that I use is correct? I haven't try it on NEC-2 yet.

Thanks again.

Regards,
Boon Phing

Robert Haviland wrote:
>
> As a first approximation, the current on a half wave dipole is a half
> sine, so the voltage is a half cosine. better approximation must consider
> wire size, resistance, feed location, and surrounding objects, which
> include the wires of an end fed system. MiniNec analysis is not accurate
> for a end feed. Use NEC2 for a good solution of the particular antenna.
>
> W4MB
Received on Wed Nov 05 1997 - 11:39:50 EST