For footprint reasons, I need a wireless transceiver that has recent range, without an external antenna. So far I have found the nRF24L01+ which has sufficient (>100 kbps) bandwidth for my needs, however the range of that seems to be 50m: NRF24L01 real life range test – Charles's Blog
Would any trace antennas let me get about 250m outdoors? If not, could I attach a really small antenna?
In my experience trace antennas can't be expected to work over about 30 m, even outside. I'm surprised that Hallard found a set that worked to 50 m, but he can't remember where he bought them!
Antenna efficiency depends strongly on length, with the shortest optimal length being about 1/4 the wavelength (perpendicular to a 1/4 - 1/2 wavelength ground plane, if possible). Also, transmitting and receiving antennas must be oriented parallel for optimal range.
I found this on SparkFun which has a 'PCB antenna' and claims 1 mile range:
It does seem to use a lot of power though, but this seems good?
Hi,
That xbee module would be illegal in the UK where the limit is 10mW for 2.4GHz.
I have some concerns about that blog entry. The blogger says the the "green" module had the better range. But he also said they had the same pinout when you can clearly see the the green module has 10 pins versus 8 on the black. I have modules identical to both those, and have been told that the green/10-way module is the older model nrf24l01, which does not support the 250MB/s setting he claims to be using for testing.
Check out this thread where I got lots of good advice from forum members crofter and pico. The early posts are about me struggling with sketches and libraries, so skip to towards the end of the first page.
http://forum.arduino.cc/index.php?topic=224418.msg1625403#msg1625403
Paul