RE: Regarding nRF51822 Proximity Range

Nazmus Sakib — Mon, 17 Feb 2014 22:13:07 GMT

Hi Janek.

Thanks for your feedback.

Yes 350 Feet I mentioned considering Line Of Sight.

My board have size constraints. For antenna my available room is around 10mm X 5mm (W X L). In this case, PCB antenna can be used? Or better Chip antenna?

Well, 350 Feet will be best for me. But if device can work with 250 Feet that will be fine for now.

My need is to measure the Proximity RSSI and show an approximate distance (between device and phone) on iPhone.

if you have any recommendation on Antenna (PCB or Chip), please advise.

Regards.

RE: Regarding nRF51822 Proximity Range

Janek Mann — Mon, 17 Feb 2014 21:35:18 GMT

Hi Nazmus,

When a module like the RFduino mentions that kind of range you can be certain that it is only under ideal conditions (in freespace, direct line of sight, no walls etc). If your application allows it, a directional antenna would help a lot (but needs to be evaluated carefully from a regulatory point of view).

The NRF51822 can manage connections at that range, but not consistently, in my opinion.

Most chip antennas are actually no better, or worse, than a good PCB antenna of larger size, so that wouldn't help much unless you have size constraints (like the designers of the module used by RFduino did).

Another issue to keep in mind that for a proximity application, the accuracy will be extremely poor at higher range. In other words, you may have a reasonable connection at one spot 350 feet away but no connection at all a foot to the side (or even a foot closer to the iPhone), due to constructive / deconstructive wave interference.