antenna and distance question

In a perfect world and assuming all things to be equal and atmospheric
conditions, line of sight etc to be good and also assuming 2.4 ghz:

What sort of line of sight distances should a 15.4dBi omni-directional
antenna be able to effectively communicate with two or three clients with
high gain (maybe 22 or 24di) directional parabolic antennas? Could this be
effective communication at a distance of a few miles? Or is that wishful
thinking?

The highest gain omni I can find in my price range is 15.4dBi. I need three
clients (and maybe soon a fourth) to be able to connect to a central
location from different directions. The furthest away is about 4.5 miles.
All client locations have line of sight to the central location.

all opinions welcome

Recently is Wi-Fi :shootout" near VegaS
a pair of Hams got 32 miles. One engineer in San Diego with illegal 1 watt
power reached San Clemente at about 70+ miles. Still got the distance with
legal FCC power, but with much reduced throughput. Regards. Hard work, but
go for it.


"mobile" <(E-Mail Removed)> wrote in message
news:%Eklb.327106$(E-Mail Removed). net...
> In a perfect world and assuming all things to be equal and atmospheric
> conditions, line of sight etc to be good and also assuming 2.4 ghz:
>
> What sort of line of sight distances should a 15.4dBi omni-directional
> antenna be able to effectively communicate with two or three clients with
> high gain (maybe 22 or 24di) directional parabolic antennas? Could this
be
> effective communication at a distance of a few miles? Or is that wishful
> thinking?
>
> The highest gain omni I can find in my price range is 15.4dBi. I need
three
> clients (and maybe soon a fourth) to be able to connect to a central
> location from different directions. The furthest away is about 4.5 miles.
> All client locations have line of sight to the central location.
>
> all opinions welcome
>
>