The relation between the number of turns and the axial ratio (helix antenna)

Hello,

In the book of <<antenna for all application>>,
whose author is John D Kraus,I want to know
the relation between the number of turns
and the axial ratio.

Axial ratio of helical antenna is depend on the last several turn of the open end, usually it is taper for lower axial ratio performance

http://emclab.concordia.ca/~trueman/..._Lecture2w.pdf

Is there any parameters different between axial mode and normal mode of helical antenna? (In term of the formuale)

Hey stefen !

Here is the relation between Axial Ration and n (number of turns) in helical antenna :

A.R. = (2n+1) / 2n

hi all,
it seems impossible to design Helix antenna in MWS, doesn't it?

Thanks!

Khang

it is not impossible to get a helix modeled in CST. Draw a circle, cover it so that it becomes a metal sheet. Later set the axis of rotation (in the icon "edge from coordinates"). When both edge and the circular sheet are done, select the surface of this sheet and click on rotate - it is just a matter of filling in the fields to set the appropriate number of turns and its height.

good luck