Hi there,
Post by Noel PeatfieldI would like to set up a shared 2mbps connection with four other
houses/flats located around a small junction. I'm planning to use a
WRT54G/WAP54G solution but I'm still wondering about range. With
distances of up to 80 feet with a couple of brick walls included is
this asking too much?
A quick Google revealed amongst many others
http://lists.nycwireless.net/pipermail/nycwireless/2001-August/003460.html
which talks about 4dB for a cinder block wall, whatever that means.
If you're in modern houses which have relatively low density walls I'd
say you probably have the equivalent of two cinder block walls per
leaf of any external wall. From the above reference I suppose that
might mean a loss of 16dB, maybe 20 or more, on top of whatever else
you have to contend with. You might just get away with it. If you
have a couple of high density walls between the stations you might be
in trouble.
Will there be vehicles passing between the houses which are linked by
radio? That could cause problems, especially if someone parks a
removal van directly between them.
How old are the walls? Foil-backed plasterboard could be a nuisance.
Are they dry walls? Water absorbs radiation strongly at 2.4GHz.
Post by Noel PeatfieldLinksys themselves are very none committal about information on range.
With good reason. :)
Post by Noel Peatfieldany good tips on judging distances in this type of environment?
I don't think calculations will help very much, so try it and see.
If you don't get good results at first, try a few alternative
arrangements. Be aware that signals are reflected from surfaces as
well as being absorbed by materials. For example put the devices in
different places to try to minimise the effect of destructive
reflections, and make use of any helpful reflections you might be
lucky enough to get. Position changes as small as a few centimetres
can make a big difference.
Try to minimise the absorption. If you can get a line of sight
between the antennas that distance is nothing, so if you can trade
distance for obstacles the extra distance probably won't matter.
Don't run the signal down a long coaxial cable if you can avoid it,
if one of the cables has to be a long, make it an Ethernet cable.
Be careful with the orientation of the antennas, rotating a dipole
about an axis that joins the two stations (that is changing from a
vertical polarization to something nearer to horizontal) can cause a
huge difference in the received signal strength.
If all else fails try some different antennas.
I'm sure there are more people out there with more ideas.
Do let us know what you find.
73,
Ged.