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All things pertaining to wireless and RF links
By static418
#137378
Hi,
I'm trying to find a wireless module for use with an ATMega328p, either Arduino or plain AVR, which is FCC Part 15 certified at a minimum. I need to produce a final device I can sell, not on a huge scale, but at least 40-50 units. My understanding is I can do this only if I use a certified wireless module.
I'm using the wireless to transmit very small data packets according to button events, and some other external input. Running on battery power, so low power is very nice. I'd also greatly prefer something that can connect to several other modules, either multi-point or a mesh network. At least 2 will link up at a time, and I really want the ability to add more to the network later. An integrated antenna would also be great, but isn't required as long as it doesn't operate at a silly frequency that I can't find chip antennas for.
Some additional info that may be pertinent: I'm trying to make the final board as small as possible. It's for a wearable application and will fit inside a glove. So whatever that means as far as wireless reception.
Thanks!
By static418
#137380
Would this work? :
http://www.microchip.com/wwwproducts/De ... e=en535967
It seems to be low-ish power, small, inexpensive, and able to do mesh networking. It's also 2.4 Ghz, which is great because I'll most likely be shipping several of these internationally and sub-Ghz frequencies run into a problem there.
I still have to check on programming tools, but any thoughts?
By Faludi
#138813
I'd give serious consideration to the XBee http://www.sparkfun.com/search/results? ... t=products, which will give you the shortest development time given the XBee's high-level and very well-documented interface. I think the other suggestions here are interesting but might be more appropriate for larger volume applications (such as >30K~50K units). There's also programmable XBees http://www.digi.com/wiki/developer/inde ... ng_Started if you want to forgo the external microcontroller.
By Sacman
#138852
I am struggling with this same problem and one of the significant drawbacks to Xbee is it's cost. At $19 for the simplest module, it adds significant cost to the final product. The other issue is their physical size. For my purposes, these things are huge!

Thanks for the link to that Microchip board. I had not seen that one and it is certainly worth looking into.

Two other possible options that I looked into are the Linx 433Mhz chip but it is not FCC approved. So I had to discard it immediately at the sacrifice of range.

The other is a TI chip. These are FC15 approved and meet the Europe and Canadian requirements and they are cheap. However, you would have to handle a couple of peripheral components (minimal) and an antenna. However, did I mention that they are cheap. They are also a QFN package so they have a VERY small footprint which is a serious consideration for me. On Digikey they are $4.20 for one. Mouser is even cheaper at $3.97. The datasheet is very clear and I think setup for these would be minor. If you ever thought you could get to 1000 of them, they are $1.40 direct through TI. If these work out for me, I would even be willing to split an order with someone to get the savings.

For proto purposes, you can get breakout boards for QFN packages that bring the pins out to a standard 2.54mm header. I even found a service that will order your Digikey part and assemble the breakout for an additional charge.

Anyway, here is the Digikey link. http://search.digikey.com/us/en/product ... ND/1014208

And last, while that Whizbee link above looks interesting, where in the world do you buy them and how much do they cost?

Luck,

Wade
By stevech
#138915
look at JeeLabs' board with the HopeRF RFM12. There's also an Arduino library available. Modern Devices sells it and maybe SFE too.