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Direction Finding was introduced with Bluetooth 5.1 (pdf) and uses of Angle of Arrival (AoA) and Angle of Departure(AoD) to determine location to sub-meter accuracy.
Enhancing Bluetooth Location Services with Direction Finding
New Bluetooth Direction Finding Feature Will Enhance Location Services Solutions
Bluetooth Enhances Support for Location Services with New Direction Finding Feature
Bluetooth Direction Finding: Angle of Arrival (AoA) and Angle of Departure (AoD)
Angle of Arrival - Bluetooth 5.1 Direction Finding Explanation
AoA and AoD: Driving Business Value Through Location