[TriLUG] WLAN Research

[Warren Myers]

On 5/22/06, Greg Brown <gwbrown1 at gmail.com> wrote:
<snip>

> need to drop the input power on your AP going into the amp.  I've found 20
> mw of power works best.


</snip>
you mean milliwatts I hope and not megawatts ?   :)

Being as this is a point-to-point link you can raise the gain on the
> antennas and the amps a bit to.  Here are your limits:
>
> Total    Amp                         Max gain           EIRP in watts
> *30dBm 1W                            6dBi                 3.98
> 29dBm 800mW                      9dBi                 6.35
> 28dBm 630mW                    12dBi                10.14
> 27dBm 500mW                    15dBi                15.81
> 26dBm 398mW                    18dBi                25.23
> 25dBm 316mW                    21dBi                40.28
> 24dBm 250mW                    24dBi                62.79
> 23dBm 200mW                    27dBi                100.2
>
> So, looking at this we have a couple options.  I'd go with Yagi antennas
> or
> dishes.  Personally I would only mess with 500 mw or 1 watt amps, too much
> freakiness on the adjustable amps.
>
> Use LMR400 antenna cables.  The other stuff has too high loss.  And mount
> the amp as close to the antenna as possible.
>
> Personally I'd go with Antennex Yagis, they are weatherproof and sealed.
> Nice.  At 14.6 dBi gain you can still go with a 500 mw amp and you'll be
> just under max power.  Anything more then 100 yards I'd consider going
> with
> dishes, but at this power level you should be ok.
>
> Use WPA between the devices too (keep the prying eyes out).  If you get
> adventerous try afterburner mode on the wrts.  I've never tried it, but I
> can't see why not.
>
> Anyway, those are my suggestions.
>
> Greg
>
> *
> On 5/22/06, Matt Dinsmore <matt at centrix.net> wrote:
> >
> > I've done this before, not locally though. We used Cisco 350 bridges.
> > Worked great, except for when it got snowy/icey which I don't think will
> > be a problem here. We had multiple sites with yagi antennas. At the
> > center we had an omni. We had a 3 mile radius. The extreme edges got
> > kinda sketchy, but 100 yards should work fine and be stable.
> >
> > I would recommend the Cisco stuff, or even the Linksys ( which is now
> > owned by Cisco ) stuff if this is tmp / on a budget.
> >
> > How is your line of site ? This is VERY important for long distance
> hauls.
> >
> > Matt Dinsmore
> > matt at centrix.net
> >
> > Carl Crider wrote:
> > > I am currently researching parts/designs for a wireless LAN here at my
> > > office.
> > > We need to connect a building that is 100 yards away from our main
> > > switch.
> > > This building houses only 5 PC's. Does anyone have suggestions on both
> > > design and local shops to buy the parts?
> > >
> > > This will be a permanent installation replacing the current
> underground
> > > fiber patching these 2 buildings. The fiber has to come up due to
> > > construction.
> > >
> > > Thanks in advance for any input.
> > >
> >
> >
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