Wireless - how far and what kit works

Toying with the idea of WiFi-ing down the village.

How far can I expect to get with what kit?

What recommendations to get from office to home - about 300m with a
couple of houses in the way?

tia


--
TonyL

"Tony Lewis" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Toying with the idea of WiFi-ing down the village.
>
> How far can I expect to get with what kit?
>
> What recommendations to get from office to home - about 300m with a
> couple of houses in the way?

Unless you can get one of the in the way house owners to repeat your signal
(with a couple of back to back Linksys WET11's or similar) or you can get
over or around the obstructions then forget it. Wifi doesn't travel through
more than 1 or 2 walls well at all.

Paul

In article <(E-Mail Removed)>,
Tony Lewis <(E-Mail Removed)> wrote:
>Toying with the idea of WiFi-ing down the village.
>
>How far can I expect to get with what kit?
>
>What recommendations to get from office to home - about 300m with a
>couple of houses in the way?

Forget doing it over that distance outdoors unless you are at roof-top
level. The power levels allowed on the 2.4GHz kit really don't cut it
unless you have genuine line of site. Even then, I'd type "fresnel zone"
into google and start reading.

Also, unless you are fantastically rich, it's going to cost oyu a lot
of money to get started!! (Assuming you already have a broadband feed
yourself). Check out Smart Bridges for some reasonable outdoor kit,
but it aint cheap! http://www.smartbridges.com/

Maybe theres a Wireless broadband operator in your area already? Where
are you?

Gordon
(Who does some work for a local wireless broadband company)

There's lots of good info at:
alt.internet.wireless

Hope this helps

JohnK
On Sat, 07 Feb 2004 23:14:55 GMT, (E-Mail Removed) (Tony Lewis)
wrote:

>Toying with the idea of WiFi-ing down the village.
>
>How far can I expect to get with what kit?
>
>What recommendations to get from office to home - about 300m with a
>couple of houses in the way?
>
>tia
>
>
>--
>TonyL

In message <c04rvb$j0t$(E-Mail Removed)>, Gordon Henderson
<(E-Mail Removed)> writes
>Forget doing it over that distance outdoors unless you are at roof-top
>level. The power levels allowed on the 2.4GHz kit really don't cut it
>unless you have genuine line of site. Even then, I'd type "fresnel zone"
>into google and start reading.

I have no personal experience of this (except to know that my wi-fi kit
goes through several walls at home with no problems). But the recent
wi-fi shootout showed some remarkable results. The world record is now
over 300 km, but that involved amplification. If you use just a clever
antenna people have managed a few kilometres. Even a Pringles can seems
to help. See:

http://home.earthlink.net/~wifi-shootout/

--
Clive Page

In article <(E-Mail Removed)>,
Clive Page <(E-Mail Removed)> wrote:
>In message <c04rvb$j0t$(E-Mail Removed)>, Gordon Henderson
><(E-Mail Removed)> writes
>>Forget doing it over that distance outdoors unless you are at roof-top
>>level. The power levels allowed on the 2.4GHz kit really don't cut it
>>unless you have genuine line of site. Even then, I'd type "fresnel zone"
>>into google and start reading.
>
>I have no personal experience of this (except to know that my wi-fi kit
>goes through several walls at home with no problems). But the recent
>wi-fi shootout showed some remarkable results. The world record is now
>over 300 km, but that involved amplification. If you use just a clever
>antenna people have managed a few kilometres. Even a Pringles can seems
>to help. See:
>
>http://home.earthlink.net/~wifi-shootout/

Sure. Great distances, but at what data rate? Stunts like that don't
really mean anything in the real world. Stick a window in the way and
it'll halve the data rate. Stick a few walls and you really are down to
the bottom of its limit, and who wants a marginal service at the very
edge of its performance, or a 5 metre dish on a mile-high pole on the
side of their house?

I've helped deploy a commercial wireless broadband service in 3
communities now and it's not that easy. Trust me. You need to spend a
lot of time, money and effort to get it right, then just as you think
you have succeeded, along come the towns CCTV systems which just happens
to use about half your avalable spectrum in the 2.4GHz band )-:

You can use whatever antennae you like, but as soon as you stick a bit
of co-ax in the path and a connector or 2, you've already lost some of
the pathetically weak (due to UK licensing regulations) signal, so
sometimes it's questionable. Look for kit with built-in flat-plate
antennae and it'll often outperform an external antennae, so then your
issue is getting the unit on the roof in line of sight to your next
hop.

Gordon

Gordon:
>Stick a window in the way and it'll halve the data rate.

Not so. My 11b wifi works perfectly trough two sets of double glazed and
leaded windows at acute angle (and 75m of clear space in between).
Regards,
Martin

In article <OkBVb.1483$(E-Mail Removed)>,
Martin² <(E-Mail Removed)> wrote:
>Gordon:
>>Stick a window in the way and it'll halve the data rate.
>
>Not so. My 11b wifi works perfectly trough two sets of double glazed and
>leaded windows at acute angle (and 75m of clear space in between).

Lucky you!

However, the point I'm trying to make is that it's not just as simple as
sticking a couple of nodes in windows when it comes to outdoor stuff,
especially if you want it to be reliable and consistent. (And out of
sight!) You'll certainly be able to provide a service between 2 nodes if
you are lucky, but IIRC the OP was going on about WiFi enabling their
village, and thats a different kettle of fish entirely.

To do it well, you really need to get up to the roof-top level and out of
the fresnel zone. Then you have the problem of channel spacing - how many
channels are there? Take a look at the spacing and you'll see that in
reality you only have 3 clear channels out of the 11 (or 13) allocated
)-: If you can find kit and antennae that can be horizontally polarised
then you can gain some margin until some home-user sticks their personal
WiFi AP on the same channel and blots out half your neighbourhood )-:

In the past 2 years I've tested various bits of kit (Avoid DLink!) for
outdoor use and haven't found anything that's really good in all
situations. If you want reliable long distance, you need a better
frequency (and equipment) than 2.4GHz and extending 2.4Ghz networks with
2.4GHz kit is witchcraft in itself - you'll end up with duplex problems,
problems with the processors in the equipment just not being up to it,
crappy software that doesn't do ARP aging, problems with the DSPs not
being able to suppress reflected signals and so on.

It can be done - right now I'm at home (rural town in Devon, not
Torrington!) with a 2.4Ghz broadband link to the world, but it takes
a lot of time, money, and effort to set it up in a usable manner, for
anything other than casual use.

OFDM is probably the future of non-line-of-sight stuff, but right now
it's expensive, and we're still going to be limited by the power levels
available to us in the 2.4Ghz band.

You might as well pay to have your local exchange enabled!!!

Good luck!

Gordon

In message <c06e5r$la4$(E-Mail Removed)>, Gordon Henderson
<(E-Mail Removed)> writes
>Stick a window in the way and
>it'll halve the data rate.

Really? That's not my experience, and having just checked it, there's
exactly the same signal strength on either side of my office window. I
assume glass has a low microwave absorption, which is why the rotating
plates in microwave ovens are made from it.

--
bof at bof dot me dot uk

On Mon, 9 Feb 2004 10:01:04 +0000, bof <(E-Mail Removed)>
wrote:

>In message <c06e5r$la4$(E-Mail Removed)>, Gordon Henderson
><(E-Mail Removed)> writes
>>Stick a window in the way and
>>it'll halve the data rate.
>
>Really? That's not my experience, and having just checked it, there's
>exactly the same signal strength on either side of my office window. I
>assume glass has a low microwave absorption, which is why the rotating
>plates in microwave ovens are made from it.

Depends on the glass. I suspect that with windows, the frame
construction is going to be as much of an issue - metal frames, semi
faraday cage etc?