WiFi network with 1600Ft between two buildings

[Guest]

Archived from groups: alt.internet.wireless (More info?)

Hi, what is the cheapest way to make a WiFi Network between two buildings
with 1600ft in between?
Thank you.
GL

 

[Guest]

Archived from groups: alt.internet.wireless (More info?)

In the 1600 ft between building are there any obstructions?

Do you have line of sight between the buildings?

What type of use are you trying to have such as a single computer on
one end talking to an access point or do you plan on bridging networks?
How important is quality and reliability?

 

[Guest]

Archived from groups: alt.internet.wireless (More info?)

On Fri, 10 Dec 2004 10:59:59 -0500, "G Lam" <No_spam_glaml@qvs.com>
wrote:

>Hi, what is the cheapest way to make a WiFi Network between two buildings
>with 1600ft in between?

Cheapest? Well, two USB radios with a 16ft max USB extension cable on
the roofs. Setup the radios for Ad-Hoc mode so exactly two computers
can talk to each other. No access point required (or useable). Older
802.11b USB radios go for as low as $15/ea. You will need a bit more
antenna gain, so shoving the USB radio inside a 1 lb coffee can will
help.

Of course, this is probably not what you wanted. It's kind hard to
offer advice without known the nature of the path (any trees), what
type of traffic you plan to move (speed), and what type of machines,
broadband, servers, etc. are at each end.


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558

 

[Guest]

Archived from groups: alt.internet.wireless (More info?)

Yes, we have line of sight between the buildings, no blockage.
Wish to have 2 or 3 computer at one end talking to an access point at the
other. If not possible, one PC talking to the access point is acceptable.
Preferred to have 11mbs or above reliable connection.
Thank you for your help.
GL

"kbloch2001" <kbloch2001@hotmail.com> wrote in message
news:1102706989.721805.21240@z14g2000cwz.googlegroups.com...
> In the 1600 ft between building are there any obstructions?
>
> Do you have line of sight between the buildings?
>
> What type of use are you trying to have such as a single computer on
> one end talking to an access point or do you plan on bridging networks?
> How important is quality and reliability?
>

 

[Guest]

Archived from groups: alt.internet.wireless (More info?)

Yes, we have line of sight between the buildings, no blockage.
Wish to have 2 or 3 computer at one end talking to an access point at the
other. If not possible, one PC talking to the access point is acceptable.
Preferred to have 11mbs or above reliable connection.
Thank you for your help.
GL

"Jeff Liebermann" <jeffl@comix.santa-cruz.ca.us> wrote in message
news:i8vjr01nhm1d3ipahisqupoop5r1vegbs4@4ax.com...
> On Fri, 10 Dec 2004 10:59:59 -0500, "G Lam" <No_spam_glaml@qvs.com>
> wrote:
>
> >Hi, what is the cheapest way to make a WiFi Network between two buildings
> >with 1600ft in between?
>
> Cheapest? Well, two USB radios with a 16ft max USB extension cable on
> the roofs. Setup the radios for Ad-Hoc mode so exactly two computers
> can talk to each other. No access point required (or useable). Older
> 802.11b USB radios go for as low as $15/ea. You will need a bit more
> antenna gain, so shoving the USB radio inside a 1 lb coffee can will
> help.
>
> Of course, this is probably not what you wanted. It's kind hard to
> offer advice without known the nature of the path (any trees), what
> type of traffic you plan to move (speed), and what type of machines,
> broadband, servers, etc. are at each end.
>
>
> --
> Jeff Liebermann jeffl@comix.santa-cruz.ca.us
> 150 Felker St #D http://www.LearnByDestroying.com
> Santa Cruz CA 95060 AE6KS 831-336-2558

 

[Guest]

Archived from groups: alt.internet.wireless (More info?)

On Fri, 10 Dec 2004 17:33:19 -0500, "G Lam" <No_spam_glaml@qvs.com>
wrote:

>Yes, we have line of sight between the buildings, no blockage.
>Wish to have 2 or 3 computer at one end talking to an access point at the
>other. If not possible, one PC talking to the access point is acceptable.
>Preferred to have 11mbs or above reliable connection.

Ok. What you need is either two transparent bridge boxes, or a
"workgroup bridge". Since you want cheap, I suggest a pair of Linksys
WAP54G boxes in "bridge mode". These will pass 32 MAC addresses which
means you can have a total of 30 computahs on the bridge.

1600ft is too far to do with the cheezy antennas that come with the
WAP54G. My guess(tm) is that you'll need want at least 14dBi dish or
panel antennas at each end. Running some very rough calculations
using:
http://www.ydi.com/calculation/som.php

The receive sensitivity is *APPROXIMATELY*:
* 54Mbps OFDM, 10% PER, -68dBm)
* 48Mbps OFDM, 10% PER, -68dBm)
* 36Mbps OFDM, 10% PER, -75dBm)
* 24Mbps OFDM, 10% PER, -79dBm)
* 18Mbps OFDM, 10% PER, -82dBm)
* 12Mbps OFDM, 10% PER, -84dBm)
* 11Mbps CCK, 8% PER, -82dBm)
* 9Mbps OFDM, 10% PER, -87dBm)
* 6Mbps OFDM, 10% PER, -88dBm)
* 5.5Mbps CCK, 8% PER, -85dBm)
* 2Mbps QPSK, 8% PER, -86dBm)
* 1Mbps BPSK, 8% PER, -89dBm)
I would aim for about 24Mbits/sec, so I'll use -79dBm for receiver
sensitivity.

Plugging into:
http://www.ydi.com/calculation/som.php
Distance = 0.255 miles
Tx power = 15dBm
Tx ant gain = 14dBi
Rx and gain = 14dBi
Tx cable loss = 3dB (including connectors)
RX cable loss = 3dB
RX sens = -79dBm (for 24 mbits/sec)

I get a fade marine of 23.7dB, which is good enough. You could
probably get away with slightly less antenna gain. A 24Mbit/sec
connection should give you about 12Mbits/sec thruput, which is
adequate.

Note that I assumed 3dB loss in the coax cable and connectors.
However, you offered no information about the location of the radios
and antennas, so this is just a guess(tm).

This solution may not be the absolute cheapest possible, but it will
work.


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# jeffl@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager jeffl@cruzio.com AE6KS