Antenna Polarisation
 

Hi,

Just wondering if someone can confirm something regarding antenna positioning. I believe the following seems to be correct, but it seems quite confusing:

(This is for a VOR) A horizontally positioned antenna is horizontally polarised in it's electrical element, and vertically polarised in its magnetic element.

This continues with:

A horizontal antenna is horizontally polarised in a vertical direction....

There is an excellent article on antenna polarity here.

If you don't get a response here, I may move this question to our Technical Forum.

Just google antenna e&h plane....

I always had the rule of thumb that:

A vertical antennae is vertically polarized in a horizontal direction.

A Horizontal antenna is horizontally polarized in a vertical direction.

It's been a while since I have done the ATPLs so I'm a little rusty. I'll check out my notes when I can be arsed dragging them out.

GG

Thanks for your help Green Goblin, I got the question correct :) I'm still unsure as to why this question falls under Navigation, as opposed to Systems...But oh well

Hi Mattoo.
Polarisation refers to the electric field so that if the antenna is horizontal so is the polarisation.
Vertcal is vertical.Keeps it simple that way .The magnetic part of the field is opposite.

If they are referring to a hori antenna polarised vertically they must be on drugs or referring to the mag field for some obtuse reason to confuse you.

In a practical sense verticals speak to verticals more efficiently, same for horis and hori's work better together.

Over long distances this can be a moving feast but line of sight the above generally applies.

The polarity of an antenna refers to the orientation of the (oscillating) electric field. A vertical antenna radiates the electric field in the vertical orientation.

The magnetic field is in "time-phase but space-quadrature" to the electric field, that is to say its strength mirrors that of the electric field with respect to time, but it propagates through space at ninety degrees to the orientation of the electric field. (quadrature in space).

Introducing the magnetic field in a discussion where the electric-field is the phenomenon of interest is in my view obtuse and designed to be deliberately misleading. Most radio equipment operates by receiving the electric-field. (However, some satellite-dish LNBs use the magnetic-field for better resistance to electromagnetic pulse damage.)