Unexpected RSSI value from Estimote beacon

My Estimote beacon is set with transmission power of +4dBm and advertisement interval of 302ms. RSSI value displayed on iOS device is normal until a distance of 10 meters from the beacon. However beyond it, RSSI value starts increasing (from -104dBm to -47dBm / -38dBm /-17dBm etc) and sometime settles at 0dBm. Since, I am trying to convert the RSSI value to distance manually, this unexpected value is creating a problem. What could be the solution? Thank you.

Hey santobedi,

Could you provide us with the details listed below?

  • iOS device models you’re experiencing the problem with
  • iOS versions
  • beacon settings: advertising interval, broadcasting power, power modes
  • battery level
  • environment in which the issue manifests itself: distance to the beacon, any potential sources of interference etc.
  • does minimizing Bluetooth usage by other apps help?
  • does unpairing any wireless headsets, fitness trackers and other Bluetooth devices from the phone help?


Hi Jacku,
I’ve checked with three different iOS devices,the details are:

  1. iOS devices: iPhone 4S (two devices) and 5S
  2. iOS versions: iOS 8.1.3 (1st 4S device), iOS 8.2 (2nd 4S) and iOS 8.2 (5S)
  3. beacon settings:
    i) advertising interval: 308 ms (2 beacons), 307 ms(3 beacons) and 302 ms (1 beacon) -total 6 beacons
    ii) broadcasting power: +4dBm
    iii) I could not find power modes in Estimote App.
  4. battery level: Estimated Battery Life is shown in a range of 250- 372 days among six beacons.
  5. Problem starts when the distance to beacons exceeds 10m. Potential interference: There are two nano cells (installed by telecom service provider) and two wifi routers nearby. I don’t think nano cell and wifi router could interfere.
  6. No other App use Bluetooth.
  7. No wireless headsets, fitness trackers or any Bluetooth devices paired with the iOS device during experiment.

Thank you for your time and considerations.