Avoiding WiFi/ZigBee Interference

vining

Here's a link that covers the topic.

http://www.xbow.com/Products/Product_pdf_files/Wireless_pdf/ZigBeeandWiFiInterference.pdf

Darkside

Very interesting and informative read.

It would seem to me looking at the frequency overlays that interference is more likely than unlikely if careful planning is not done.

Thanks for the link VAV.

DHawthorne

The 2.4GHz bandwidth is getting crowded. It seems to me a spectrum analyzer is going to become a necessary tool very soon, if not already. It's one thing if you are aware of every single wireless device on the premise, but what about devices that infringe on the airspace that you are not aware of, like a neighbor with WiFi and a hidden SSID, or harmonics from a high-tension power line?

Darkside

This overcrowding issue is indeed a problem. I'm not sure about the FCC rules in the states, but cordless phones of old all use 2.4GHz band for operation.

The other little boxes sitting on 2.4GHz that thankfully aren't too common any more are the AV wireless senders.

W recently had a service call to resolve 'dodgy pix' on a TV and it turned out to be the cordless hand home phone 2.4GHZ carrier splattering the AV sender when in use.

Solution was easy. Throw the phone out and get a digital version or throw the sender out and get the 5.xGHz flavor.

I can see us all having to be on site with Netstumbler, Airmagnet and Studio!

vining

Stephen Bolton wrote:
I can see us all having to be on site with Netstumbler, Airmagnet and Studio!

And Wi-Spy. It's a $99.00 spectrum analyzer that obviously covers the wi-fi spectrum. It may go high enough to include the upper channels of ZigBee (25 & 26) if it cover the the complete wi-fi range including the international. Some one on the forum was getting one a few months back and it would be nice to know how it worked out.

In resdiential applications using ZigBee on channels 25 or 26 would be the way to go as it only needs one channel for the gateway and all repeater. All the same channel. That is unless you need seperate Personal Area Networks (PAN) which then means you'll need to invade the wi-fi range here in the US. You guys overseas with wi-fi operating on 1-11 and above have no safe range so you have to spot an empty space between the wi-fi channels and then hope the Panasonic multi cell cordless phones if installed don't get you. In commercial installations where it's more likely to need several different ZigBee PANs it should be interesting.

If the job has 802.11N you might want to just walk away.

pauld

vining wrote:

And Wi-Spy. It's a $99.00 spectrum analyzer that obviously covers the wi-fi spectrum. It may go high enough to include the upper channels of ZigBee (25 & 26) if it cover the the complete wi-fi range including the international. Some one on the forum was getting one a few months back and it would be nice to know how it worked out.

I did buy the Wi-Spy, and think it is great. The Wi-Spy does cover the complete wi-fi range and does include ZigBee channels 25 & 26. Wi-Spy is easy to use and gives the user a quick way to see which channels are the best to use in a given project. This has come in handy in a few locations, helping us solve some weird issues. I beleve Wi-Spy is well worth the price. If you can afford it I would get a Wi-Spy, with AMX using both wi-fi and ZigBee I think we will all need it at some point.

Paul

[Deleted User]

Is this the right price?

vining wrote:

And Wi-Spy. It's a $99.00 spectrum analyzer that obviously covers the wi-fi spectrum. It may go high enough to include the upper channels of ZigBee (25 & 26) if it cover the the complete wi-fi range including the international. Some one on the forum was getting one a few months back and it would be nice to know how it worked out.

In resdiential applications using ZigBee on channels 25 or 26 would be the way to go as it only needs one channel for the gateway and all repeater. All the same channel. That is unless you need seperate Personal Area Networks (PAN) which then means you'll need to invade the wi-fi range here in the US. You guys overseas with wi-fi operating on 1-11 and above have no safe range so you have to spot an empty space between the wi-fi channels and then hope the Panasonic multi cell cordless phones if installed don't get you. In commercial installations where it's more likely to need several different ZigBee PANs it should be interesting.

If the job has 802.11N you might want to just walk away.

This looks to be a very interesting product as a diagostic tool. (No endorsement implied)

I did a search and found it for $199.00 USD. Can it be purchased for half that or was your cost a typo?

matt95gsr

B_Clements wrote:

I did a search and found it for $199.00 USD. Can it be purchased for half that or was your cost a typo?

I believe the deal is that the $99 price was supposed to be an introductory price for the first year or so that it was out and the accompanying software was a bit less evolved and pleasing to the eye. IIRC, the introductory price expired around the first of January or February of this year and the "real" price of $199 took effect. Not sure how long this will last, but it appears that ThinkGeek still has them at $99.