The <answer>polarization</answer> of an antenna refers to the orientation of the electric field (E-plane) of the radio wave with respect to the Earth's surface and is determined by the physical structure of the antenna and by its orientation; note that this designation is totally distinct from the antenna's directionality. Thus, a simple straight wire antenna will have one <answer>polarization</answer> when mounted vertically, and a different <answer>polarization</answer> when mounted horizontally. As a transverse wave, the magnetic field of a radio wave is at right angles to that of the electric field, but by convention, talk of an antenna's "<answer>polarization</answer>" is understood to refer to the direction of the electric field.
Whats understood in reference of direction of an E-plane?
polarization