Anyone know how to set up a wireless network...

[jc8654]

...over a 20 mile link? Lol.

In the lab I'm working, we have a wireless link running from a base station at around 4,000ft up to a summit station at 14,000ft. The line of sight distance is in the region of 20 miles to the summit. The summit station then relays the signal (using a second independent system) to another station about 5 miles away.

Now, there a nice link up there which manages about 2Mbps at the moment however we'd like to up this to a higher speed link. Also, in bad weather the current link grinds to a halt so it would be nice to be able to have a higher bandwidth in good weather so that when it's cloudy etc we still get decent speeds.

I understand I'm going to need directional antennas etc but I just wondered if anyone had experience with this kind of stuff (as the person who set up the first link no longer works in the lab!).

[jc8654]

It appears for once, I've managed to beat everyone's technical knowledge on the forum! I think that's a first. :-p

[eUKhost.com]

It appears for once, I've managed to beat everyone's technical knowledge on the forum! I think that's a first. :-p

hehe. This will be answered within 24 hours.

[jc8654]

*Starts stop watch*

And I want a minimum of 20Mbps.

[Brian]

...over a 20 mile link? Lol.

In the lab i'm working, we have a wireless link running from a base station at around 4,000ft up to a summit station at 14,000ft. The line of sight distance is in the region of 20 miles to the summit. The summit station then relays the signal (using a second independent system) to another station about 5 miles away.

Now, there a nice link up there which manages about 2mbps at the moment however we'd like to up this to a higher speed link. Also, in bad weather the current link grinds to a halt so it would be nice to be able to have a higher bandwidth in good weather so that when it's cloudy etc we still get decent speeds.

I understand i'm going to need directional antennas etc but i just wondered if anyone had experience with this kind of stuff (as the person who set up the first link no longer works in the lab!).

usps .

[jc8654]

usps .

I said 20Mbps not 20 bits per year!

[paul]

Probably you will need a multi-point radio operating system such as LMDS/WiMAX.

[jc8654]

Both of those systems only have a range of 5 miles tops with max bandwidth of 3Mbps. I do have a reasonable idea now about what to set up but I'm waiting for the 24 hour Mark challenge before I let the cat out of the bag!

[flesso]

A really long ethernet cable?

[eUKhost.com]

Hi JC


I' am posting this on behalf of our Network Engineer :-

Since you want to upgrade existing wireless bandwidth from 2Mbps to 20Mbps, I would like to know your current setup. This will help me to assist you. Please let us know your current wireless deployment setup in detail including the devices you are using.

To upgrade to 20Mbps circuit, your indoor as well as out door unit should have capability of carrying 10 E1/T1 circuit. Do they have that much capacity?

How is your wireless connectivity, is it point to point or Multipoint? Are you using URB (unlicensed radio band)?

What is the frequency your wireless antenna is set at? Is there any obstacle like any building, tree between your antenna and hub antenna? I mean in line of sight.

[jc8654]

A really long ethernet cable?

Maximum practical length is 100m.

[jc8654]

Since you want to upgrade existing wireless bandwidth from 2Mbps to 20Mbps, I would like to know your current setup. This will help me to assist you. Please let us know your current wireless deployment setup in detail including the devices you are using.

To upgrade to 20Mbps circuit, your indoor as well as out door unit should have capability of carrying 10 E1/T1 circuit. Do they have that much capacity?

How is your wireless connectivity, is it point to point or Multipoint? Are you using URB (unlicensed radio band)?

What is the frequency your wireless antenna is set at? Is there any obstacle like any building, tree between your antenna and hub antenna? I mean in line of sight.

Current setup - 4 WiLan VIP 110-24 units - transmitting at 2.4GHz. Base station with 6ft vertically polarised parabolic antenna with 30dB gain. Sector antennas (x2) at summit with 17dB gain and 1 final sector antenna (17dB) gain at final location. See photo attachments.

OVL antenna 4-26-04, small.jpg
OVL antenna back 4-25-04, small.jpg
new radio box 5-18-04, small.jpg

The units would be connecting in to a Gbps network so I don't see the capacity is a problem.

Direct line of sight is possible.

Further specs of path analysis in PDF (for the long 20 mile link) - http://www.deepspace.ucsb.edu/wirele...k_analysis.pdf

For those of you who are interested, put the Lat and Long into Google Earth and look at the terrain!

Base: 37°21'37.814' N, 118°19'36.037' W
Summit: 37°38'03" N, 118°15'20" W

[eUKhost.com]

Hi JC,

Here's what our Network admin says :-

The “VIP 110-24” wireless device which you are using uses 802.11b protocol which supports maximum 11 Mbps bandwidth with -82 dBm Receive Sensitivity. Currently, Receive Sensitivity is set to -86 dBm on your “VIP 110-24” device for 2Mbps bandwidth. This device only supports BPSK, QPSK, CCK Radio frequency modulation. However, you will need a device like https://www.broadbandbuyer.co.uk/Sho...ProductID=4482 which supports Orthogonal Frequency Division Multiplexing (OFDM) RF modulation to get more than 11Mbps bandwidth.



With “VIP 110-24” http://passthrough.fw-notify.net/dow...AN%20Radio.pdf you can get max 11 Mbps bandwidth and for that you need to adjust antenna to operate at -82 dBm Receive Sensitivity.

[jc8654]

That's nothing I didn't already know. :-p I was more on about specifics for antennas etc. the ensure there is enough gain in the system.

[DPS Computing]

I would like to add something useful to this conversation .

Ever thought about giving up?

[jc8654]

Some of us aren't quitters David.

[DPS Computing]

Some of us aren't quitters David.

Haha, no some of us are realistic I'll admit .

[eUKhost.com]

Haha, no some of us are realistic I'll admit .

haha.

I think he should have managed to figure out some solution by now.

[eUKhost.com]

Hi JC,

That snow and those beautiful mountains in the background look awesome. I am ready to come there and fix your networking problem.

[Ben Stones]

Hi JC,

That snow and those beautiful mountains in the background look awesome. I am ready to come there and fix your networking problem.

I'm not sure if you can get those sorts of mountains in the UK, but if that snow is still there during summer then we have a serious global warming issue .