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New Member

Association Delay

Im trying to connect to sites using a wireless 340 bridge with an estimate distance of 17KM. During the association process, im not sure how long would it take the devices to associate. There should be considerable latency for this but would it take 20 mins or 1hour? or better yet leave it overnight?

7 REPLIES
New Member

Re: Association Delay

What type of antennas are you using? At that distance only parabolic dishes will work. Have you cleared the fresnel zone (are the antennas high enough)? When you did the install, did you use the diagnostics to tune for max signal stregnth?

New Member

Re: Association Delay

340 wireless bridge with 21dBi solid dish and is using 50ft low-loss cables. Is the association speed the same regardless of distances?

New Member

Re: Association Delay

It sounds like you're losing a lot of packets. Try using a lower speed (like 1Mbps) and see if it's any better.

If not, then there's probably a problem with the fresnel zone or LoS.

New Member

Re: Association Delay

You could also be having an issue with the bridge itself - I had a similar problem on a 2 mile hop, once I changed out the bridge, the link came up with out a problem. So if you have a spare bridge, try swapping out one end and see if things get better.

Gerri

New Member

Re: Association Delay

hi , i think you should change your modulation to MOK from cck if you are using low Rate;such as 1Mbps-2Mbps .i had this prob too. i changed my modulation to this and used low rate such as 5.5_11Mbps.oh, you should check your Encapsulation , if you use BridgeMode you should set your EncapType in RFC1042 . it`s My Configuration and works good.

now i have a question : do you have PacketLosts to your any Radio on your bridge?if yes, you should changed your Frequency .

Mohsen@nixtechnologies.com

New Member

Re: Association Delay

I don't think your question was actually answered, but yes your association speed should be within seconds irregardless of the distance if your signal levels are within operational limits.

The other suggestions that were given will help: lowering your data rate should increase your attainable distance, parabolic antenna's with definately increase your range and will also reduce interference from other radio networks with the vacinity of yours as they have a much narrower beam width. Ensureing that you are high enough to clear the fresnel zone is also very imoortant for long range applications **cisco has a good utility for calculating this at (http://www.cisco.com/warp/public/102/wlan/faq-hardware-us-calc.xls)

I would also suggest using a Nema Enclosure located as close to the antennas as possible to eliminate the loss due to Coax, alternatively you could also use an Amplifier with will improve your power level leaving the antenna.

In our systems we routinely incorporate an outdoor 100mW amp. located at the antenna to practicaly reduce all loss associated to the cabling. an Amp will also provide you with some added receive gain as well.

The key to any wireless network of any distance is a high signal to noise ratio.

If you need any more suggestions please post or contact me.

David Fulgham, AScT

ComGuard CTS

david@comguardcts.com

867-979-3292

New Member

Re: Association Delay

One other thing. May sound silly, but some folks forget to set the distance setting off the default 0 km. Works in the lab, but doesn't work in the field. Assuming this is good, lower the speed to verify and align the link. Then you can try the higher speeds.

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