Polarity of Parabolic Antenna?

What is the polarity of a solid parabolic antenna for 2.4GHz? As i
assume that grid antenna's polarity is on the basis of its grids
alignment i.e if virtical lining then vertical polarity if horizontal
then horizontal polarity. But in solid parabolic antenna there are no
grids so what will be polarity?

If its effected on the basis of Feed of antenna then how to set
specific polarity if we are using cantenna, wave guide or quad as Feed
of antenna.

"Jack" <(E-Mail Removed)> schreef in bericht
news:(E-Mail Removed) om...
> What is the polarity of a solid parabolic antenna for 2.4GHz? As i
> assume that grid antenna's polarity is on the basis of its grids
> alignment i.e if virtical lining then vertical polarity if horizontal
> then horizontal polarity. But in solid parabolic antenna there are no
> grids so what will be polarity?
>
> If its effected on the basis of Feed of antenna then how to set
> specific polarity if we are using cantenna, wave guide or quad as Feed
> of antenna.


Its not the grid but the antenna itself.....


Marcel

--
Posted by news://news.nb.nu

Depends all on your feedhorn. A basic can antenna when holding it with the
connector down or up its vertical...... If your using a dipole feed it's all
the same. There are a few people who favour the quads and/or double quad
feeds and i can't bloody recall... Newho the grid or dish or reflector
doesn't set your polarity. Unless your antenna is a yagi.. If the reflector
or driven elements aren't in phase they don't count

"Jack" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> What is the polarity of a solid parabolic antenna for 2.4GHz? As i
> assume that grid antenna's polarity is on the basis of its grids
> alignment i.e if virtical lining then vertical polarity if horizontal
> then horizontal polarity. But in solid parabolic antenna there are no
> grids so what will be polarity?
>
> If its effected on the basis of Feed of antenna then how to set
> specific polarity if we are using cantenna, wave guide or quad as Feed
> of antenna.

(E-Mail Removed) (Jack) wrote in message news:<(E-Mail Removed). com>...
> What is the polarity of a solid parabolic antenna for 2.4GHz? As i
> assume that grid antenna's polarity is on the basis of its grids
> alignment i.e if virtical lining then vertical polarity if horizontal
> then horizontal polarity. But in solid parabolic antenna there are no
> grids so what will be polarity?
>
> If its effected on the basis of Feed of antenna then how to set
> specific polarity if we are using cantenna, wave guide or quad as Feed
> of antenna.

Polarity is actually a function of the driven element of the antenna.
A parabolic dish is simply a reflector. The polarity of the driven
element is what matters.

If thus if the driven element is horizontally polarized then the
assembly is horizontally polarized and vice versa...

-m-

"Jack" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> What is the polarity of a solid parabolic antenna for 2.4GHz? As i
> assume that grid antenna's polarity is on the basis of its grids
> alignment i.e if virtical lining then vertical polarity if horizontal
> then horizontal polarity. But in solid parabolic antenna there are no
> grids so what will be polarity?
>
> If its effected on the basis of Feed of antenna then how to set
> specific polarity if we are using cantenna, wave guide or quad as Feed
> of antenna.

While all of the above responses are correct, it should be stated that some
grid antennas will not function properly if you just rotate the feed 90º
because the grid spacing is not the same in the horizontal and vertical
directions. Generally speaking, for grid antennas you should rotate the
entire grid and feed to change polarization -- better yet, just follow
manufacturer's instructions.

Cantenna, wave guide or quad polarization is the same when used with a
parabolic reflector as it is without; the reflector doesn't change the
polarization.

Don W.