how to find feed gap of half wave dipole antenna

how to design the feed gap of half wave dipole antenna,when it is at the center and i want vary the position of the feed gap to the ends?

how to do this?

please any documents on this send to ashoka856@gmail.com

plz help

Ideally the gap between arms of a dipole should be lowest as possible, to get uniform current distribution on both arms.
But this is not possible in practice, and the gap is given by the physical dimensions of the balun used.

hi vfone thanks.

is ther any method to find the feed gap, theoritically,
plz can you help me how to calculate or idea behind this