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Hi all

Not sure if I am in the correct section, but I am sure a mod will soon tell me if not.

I have a school that I look after, which has approximately 16 access points. The access points are only 11b standard as they have been in for over 4 years now.

Until recently we experienced no issues at all with wireless coverage. That is until about two months ago with a new Hutchinson mast was erected across the way from the school.

The only part of the wireless that is affected by the loss of coverage is the section nearest the mast.

The AP's allow cleints to connect then drop the connection within 20-30 seconds then pick them up again. I am confiden that it isnt a hardware issue as we have relocated AP's to more 'protected' parts of the school and they work perfecty fine.

I have spoken with Hutchinson and they tell me they are operating at 1.9GHz and 2.1GHz and therefore should cause no issues.

I have also spoken to Ofcom, however as they stated I am woring in a licence free section of the spectrum.

The nearest houses are some 500M away from the school building.

Any body else had an issue like this?

BCB -

In short, I haven't seen this exact situation before.

You may want to try a wireless spectrum analyzer of some sort. If you don't already have one, MetaGeek offers a fairly inexpensive one.

http://www.metageek.net/

It may not be as glorious as AirMagnet's version but it sure is a lot less expensive:
http://www.airmagnet.com/


It may help in proving the interference is coming from a particular source. That being said, it doesn't mean you can change what they are doing - only gives you more informed options of what to do about it.

Regards,
Brett C.

Hi Bret

Thanks for the advice. I did think about an analyser, but cost was a serious factor.

I have had a brief look and the Wi-spy analyser and cost certainly isn't a barrier.

Although as you say, even if I find the root of the problem, it may be somebody else opperating in the same spectrum, in which case I cant do anything about.

My biggist concern currently is that the registers are all taken using wireless tablets!!!

Regards

BCB

If there is massive interference, the party generating the interference may be exceeding FCC limits and could be convinced to either reduce their transmissions or face a visit by a local FCC representative.

If they are trashing the spectrum and don't know it, you can do some direction finding to determine who the offending party is and help them understand what they're doing. A spectrum analyzer will help you determine exactly where the interference is coming from, especially when it's not coming from a Wi-Fi source (you could use many other inexpensive or free tools, like NetStumbler, to analyze Wi-Fi signals). If it is a Wi-Fi source, you could help them understand how to better deploy their WLAN (and maybe make some consulting revenue in the process).

The key here is determining exactly what and where the offending source is then being able to show the owner what it's doing to the surrounding environment. This is unlicensed spectrum but there are limits to what people can legally do in it. They are not allowed to consume all airwaves nor deny you access to your own WLAN... they must play fair with their neighbors.

Joel

Excellent, Thanks for your recommendations.

I orriginally used NetStumbler to identify the AP's that were being 'interfered' with. This only found the AP's that were on my clients network.

I will send the client a report and recommend that a survey be carried to determine the exact cause of the interference.

One possibility that was recommended by a telco was may be either a local taxi company has overstepped their frequency or somebody in the local area is running something that they shouldn't.

Thanks again for your help.

BCB

Most taxi companies operate in the 450-470 MHz band so I serioulsy doubt they'd be causing the problem.

Joel