Vertical Antenna-Animation

Vertical antenna:

First antenna is a 1/4 wavelength Vertical Dipole
Second antenna is a 1/2 wavelength Vertical Dipole (Collinear Array)

  1) a vertical antenna is omni-directional;

  2) the ground plane (reflection) creates virtual elements;

  3) and the effect of adding more elements (Collinear Array) on

     directional gain. --Less sky & ground waves.  

 As the second dipole is introduced, note the Flattening of the pattern, this is effectively doubling the Antenna Gain, i.e., reducing the skywave and groundwaves.

Hardwork Can Never Ever Fails...

Best Luck..