0
\$\begingroup\$

I'm designing a smartphone app that gets advertising transmissions from N BLE beacons that transmit to M meters (approximately), for kind-of indoor-navigation. My goal is to maximize N and M as possible.

AFAIU the bigger N is the more noisier the air (the transmission-medium), so there is some upper bound of N that beyond it the air will be too noisy and the app won't work well because of frequencies collision

Let's say the beacons transmit 1 time per second, and M = 2 meters - what is the upper bound of N approximately? and what if M = 20 meters?

\$\endgroup\$
2
  • \$\begingroup\$ 1) Maximizing M is not a good idea for indoor navigation. How can you know where you are when you receive all beacons? 2) M is not a constant with BLE. Because of antenna directivity and indoor reflections, M can be 2m to 20m for the same beacon. \$\endgroup\$ Feb 12, 2020 at 19:25
  • \$\begingroup\$ The use case isn't real indoor Navigation, for the sake of simplicity let's say we need only proximity awareness. When setting the beacon transmission power it possible to control approximately the range of the signal, and let's neglect the effect of the reflection \$\endgroup\$
    – o.z
    Feb 12, 2020 at 20:31

1 Answer 1

0
\$\begingroup\$

BLE has 3 advertising channels with no interference in the frequency band of 2.4 to 2.48 GHz. A beacon transmission can be done in min. 20ms. So the upper bound for N is 3ch*1sec/20ms=150 beacons.

\$\endgroup\$
2
  • \$\begingroup\$ there are only 3 advertising channels, which used by each beacon advertising event \$\endgroup\$
    – o.z
    Feb 13, 2020 at 9:43
  • \$\begingroup\$ @o.z Thanks, I edited my answer accordingly. \$\endgroup\$ Feb 16, 2020 at 18:59

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.