On Fri, 21 Nov 2008 21:51:16 -0800, DaveC wrote:


Is it true that the higher the gain the flatter the "donut" shape of the
sensitivity field?

That is the only way to get actual gain from a (horizontally)
omnidirectional antenna (excluding any MIMO designs).

Flattening the vertical radiation pastern may have severe drawbacks
especially if the mast is swinging in the wind or some weak (e.g.
indoors) users are close to the base of the mast.

Paul OH3LWR