802.15.4 to WiFi gateway

Wireless & IoT
1

Hey everyone,

I am currently working on a project that includes designing a 802.15.4 to IP gateway. It would be much more interesting for me to have the IP side carried by a WiFi connexion rather than ethernet…

However I am facing some issues and questions about designing such a gateway (with WiFi). I know that 802.15.4 and 802.11 operate on the same 2.4 GHz frequency band, and that they differ in terms of power/bandwidth and modulation. To my understanding, this could lead to RF interferences, and 802.15.4 and Wifi coexistence has been discussed for a while. However, I figured that companies like Digi or Libelium manufacture such products.

In my project, I would like the whole design to be relatively small (a few inches long and large), meaning the antennas would be close (but as far as possible from each other!).

Do you think there’s a special process (hardware and/or software) involved/required in the design of such gateways?

I thought of good channel positioning, RF isolation (although I don’t have a clue if that is even the point here)…

Does any one have some experience on building such a thing or some knowledge to share on how it should be done?

Any help greatly appreciated!

Thanks!

2

I’ve done '15.4 to IP (802.3 ethernet).

From your questions, sounds like you need more experience with microprocessors before undertaking a DIY.

There are fairly inexpensive commercial products that do this, such as from Digi International.

3

Hey Stevech,

Thanks for writing,

I happen to have some experience with microcontrollers, in fact I am not so concerned about the programming part, this is more of a networking question! I’ve also done 802.15.4 to ethernet, but I would like to know if someone in the community ever had an experience with a 802.15.4 to Wifi design, and how the coexistence between the two networks went in that context.

4

lots of 802.11 modules out there with microprocessor interfaces via UART and SPI.

Another option is a cheap Ethernet to WiFi bridge- guts of consumer product.

5

Yes, of course. But that does not tell me how it would do with an xbee or whatever on its side (although I am more concerned about the xbee’s operation in that scenario)!