High Resolution Beacon-Based Proximity Detection for Dense Deployment

The emergence of Bluetooth low energy (BLE) beacons has promoted the development of proximity-based service (PBS), which is a context-aware application delivered subject to the Proximity of Interest (PoI). Most commercial applications use the sequential proximity detection with a fixed scanning mechanism to identify the target PoI. Such sequential execution, though is able to produce reliable detection, suffers severe performance degradation especially when the number of deployed beacons in the vicinity increases. To understand the effects of dense deployment, we conduct an empirical investigation and derive the statistical properties of both received signal strength (RSS) and signal inter-arrival time. In light of the statistical insights, this paper proposes a high resolution proximity detection using an adaptive scanning mechanism fusion with a spontaneous Differential Evolution ( AS+sDE ). This novel approach enables the receiver to adapt its scanning duration conditioned on the deployment density and make an almost spontaneous detection in parallel with the scanning. The feasibility of the proposed approach is verified by both simulations and real-world implementations. For a density of ≤5 beacons/m2 , AS+sDE achieves a superior performance with a high accuracy rate, i.e., on average <1s is spent to guarantee at least 90 percent accuracy.