A BLE and UWB Beacon-Assist Framework for Multiuser Augmented Reality Synchronization Across Multiple Devices in Shared Environments

The challenge to synchronize augmented reality (AR) across sessions/devices has been solved by relying solely on vision-feature mapping, which is suboptimal in scaling workable space and flaws under visual changes in surroundings. This study implemented AR synchronization solutions utilizing location beacon technology, namely Bluetooth Low Energy (BLE) and Ultra-Wideband (UWB), to discourse scalability issues and inconsistencies in the existing AR system. The framework is bifurcated into two approaches: BLE-assist and UWB-assist AR synchronization. The BLE-assist method utilizes iBeacon technology for room context recognition, integrating with Apple's ARKit ARWorldMap and Google's ARCore Cloud Anchors. The UWB-assist solution employs precise beacon ranging capabilities fusion with the device's azimuth to establish fixed spatial reference in AR across sessions/devices. Comparative evaluations show that the UWB-assist approach outperforms the BLE-assist approach in reliability across environmental variations, as it always successfully resolves virtual anchors with a near-constant latency average at 25 seconds, regardless of the physical setting changes. Conversely, the BLE-assist implementation tends to be more accurate in resolving virtual anchors with a mean of 0.02 metres in position error and within 0.03 radian in orientation error. In the UWB-assist approach, computed fixed spatial references have an average disparity of 0.04 metres and 0.11 radians in pose. The UWB-assist approach is ideal for scenarios requiring consistently successful localization with acceptable accuracy. In contrast, the BLE-assist approach is more suitable when demanding finer precision in virtual anchor poses with the performance tradeoffs when the surroundings are altered, such as for destinated short-lived AR sessions.