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All,

Some damn fool has gon out and purchansed a Bluetooth scanning system and I have to deploy it smack dab in the middle of our facility that is heavliy saturated with 2.4GHz WiFi as well as some 5 GHz. The bluetooth readers as class 1, 100mW designed to track BT enabled devices as they move about our facility. Proplem is, I don't have a spectrum analyzer. I've got AirMagnet and a Fluke WiFi analyzer that does show the interference, but not in a way that I can quantify and say 'yes' or 'no' to this deployment.

Does anyone have any experience with such high power BT devices?

I do not have any experience with BT deployments but I am curious to know the duty cycle when the device you mentioned is activated.

What is the device make and model? If it s only a BT scanner then it might not have a high duty cycle because most of the time it will be in monitor mode anyway.

Seems to me that if they want you to deploy something, they need to supply you with the tools to analyze it. This gives you another great reason to obtain a spectrum analyzer lol.

Please fill me in on any results you get if you end up "HAVING" to install the device.

It's a USB BT device plugged into a small unix box, which then goes to a 802.11 device configured as a wireless routing client as the connection to our network. Those devices will be 5GHz when able, but some will be 2.4. Actual device is a Sena Technologies UD-100. Don't know about the duty cycle - doubt if the vendor knows much about it either.

When I look at the channel screen on my Fluke AirCheck, there is a noticeable increase in 802.11 traffic right across the spectrum, and an even larger increase in non-802.11 traffic. Seems to be skewed towards the higher end of the spectrum. AirMagnet does not show anything obvious. Wi-Fi clients do seem to be affected, (based on my Fluke listening for their probes and reporting channel and strength) but not by a horrible amount. It's difficult to say exactly how much, because the baseline is always moving!

My reading on BT suggests that it trys to stay out of the way of WiFi so perhaps there won't be a big deal. If you can suggest some way to test this better (short of flying you out with a spectrum analyzer ;-) - I'd appreciate it. My biggest concern is that in areas that are already busy with a lot of WiFi traffic, the extra noise will fill up the spectrum. Is my concern valid?

Thanks,

Mike

Mike,

Invest in a WiSpy analyser fom Metageek.net, you need a tool like this and it's affordable.

If you are concerned about the effects of the BT system, do some throughput tests with iperf (Google it) Finally get a frame capture. Make both of these tests with BT on and off and see if you can see any noticeable differences. Look for fragmentation and retries, both of which indicate layer 1 problems. Be sure to benchmark first to see what normal traffic looks like.

Final thought - have you approached the manufacturer for their deployment guide?

NM

Thanks - the WiSpy looks pretty capable and at good price. I've already run iperf and noticed no discernable degredation. AirMagnet hasn't really complained either, so I don't think a frame capture will show much in this case. I'll give it a try if I have time.

The vendor is pretty lame - more of an integrator - not much help there.

I love the Paris Hilton line in the WiSpy video. It made my day!

I have worked in areas with many (5) Sena Bluetooth AP's running simultaneously. We never had any Wi-Fi problems caused by them.

Any BT device running AFH is unlikely to cause a problem.