i asked sparkfun if its critical to have the SMD antannea to be clear from any ground planes and traces… (the docs seem to require it) and here is what sparkfun (pete) had to say. (i also asked him how critical it is to have handshaking as well)
Hello,
How critical is it that the smd antennae be clear from a ground plane and other traces?
You can expect performance to be roughly proportional to the antenna’s proximity to other metal. How critical is that? That depends what sort of performance you want. I don’t have any firm numbers that say how much for how far, but I would design with this in mind.
(I want to use this for my robot but its easiest to slap the Bluetooth chip on top of some analog traces and a ground plane running underneath).
You can certainly try it. If it doesn’t work well enough, you can make a little extending header (or something of the like). That’s an easy fix.
The documentation says to avoid this, but I do not need >100ft range, more like 20 ft& (someone mentioned that in RF it doesnt matter if its 3 ft or 30ft)
And is it that critical to go for handshaking?
Critical? Not so much, really. The nRF2401A’s do all their own CRC, addressing, etc. When configured right, they’re pretty dependable. I don’t think it’s critical at all for Blue Tooth modules. It might also help to have a look at the comparative range test I did last week:
http://www.sparkfun.com/tutorial/how_far/How_far.htm
Sorry we didn’t get the Blue Tooth stuff in the test. It’s a bit more complicated to configure these things for the sort of test I did, but it will happen sometime soon.
Since I couldnt find these answers in the forum, Ill post your response.
Then I’ll say “word up” to all my homies out there!
Pete
