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ioscllocationmanageribeaconindoor-positioning-system

Indoor Navigation using I-Beacon

I am doing an Indoor Navigation using I Beacon. I want to know the current location of the user. Is there any property for beacon like proximity or accuracy where i will get the distance of the beacon from the userLocation. Please help me to get the distance of the beacon from the userLocation. According to my knowledge beacons have accuracy, proximity and Received Signal Strength (RSSI). So it will be helpful if i get a clear idea of what these accuracy, proximity and RSSI means and how i can calculate or get the distance of the beacon from the userlocation.

Thanks in advance.

Solution

  • The CLBeacon class contains three properties which are related to the distance between the beacon transmitter and the receiving device:

    1. rssi: The Received Signal Strength Indicator, measured in dBm, tells how strong the beacon signal was as averaged over the last one second ranging cycle. It originates from the radio receiver on the Bluetooth LE chip, and has a large amount of variation due to radio noise.

    2. accuracy: This field provides a distance estimate in meters between the beacon and the receiving device. It is calculated using a mathematical formula from a running average of the rssi over 20 seconds, combined with a reference measurement of what the rssi is expected to be for the beacon at a distance of 1 meter. This reference measurement is transmitted inside every iBeacon packet. The field also has quite a bit of variance and error due to radio noise, signal multipath and reflections.

    3. proximity: This field is derived from accuracy, and puts that value into one of three "buckets" depending on a range of values. "Immediate" is for an accuracy under 0.5 meters, "Far" is for an accuracy of 3 meters or more, and "Near" is for any value in between.

    None of these fields can be used by themselves for indoor positioning, which is a much more complex subject. However, the first two fields can be useful inputs depending on the technique used.

    More details are available here: http://developer.radiusnetworks.com/2014/12/04/fundamentals-of-beacon-ranging.html