Beacon detection with monitoring beacon region doesn't work as expected when the app is in background.

Originator:sanggeon.park
Number:rdar://28608501 Date Originated:04-Oct-2016 03:33 PM
Status:Open Resolved:
Product:iOS Product Version:iOS 10.0.2
Classification:Bluetooth Reproducible:Always
 
Area:
Bluetooth

Summary:
iPhone cannot find a beacon in region even the beacon is always beside the phone (in 50 cm) when the app is in background and the 'Uses Bluetooth LE accessories'  background mode is enabled.
The TxPower of beacon is +4dB (maximum), and advertising interval was 800ms, 500 ms and 350 ms.

Steps to Reproduce:
1. clone https://github.com/SanggeonPark/iOSRangedBeaconInRegionProblem.git
and run it on the phone.
2. Start advertising iBeacon with "73676723-7400-0000-FFFF-0000FFFF0007" proximity UUID very close by the phone. Set TxPower of beacon as +4dB (max) and Advertising interval as 800 ms.
3. Press home button on the phone to put the app in the background.
4. After an hour open the app and check the ranged beacon in region event.

Expected Results:
The app could get the ranged beacons through the CLLocationManagerDelegate method (locationManager: didRangeBeacons:inRegion:) call even the app is running in the background.

Actual Results:
Over 30% of CLLocationManagerDelegate method (locationManager: didRangeBeacons:inRegion:) calls doesn't deliver any beacon. 

Version:
10.0.2 (14A456) 

Notes:


Configuration:
iPhone 6s 64GB Model A1688

Comments


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