Obstruction-aware Bluetooth Low Energy Indoor Positioning

Bluetooth low energy (BLE) technology is demonstrating significant potential in providing accurate and reliable positioning indoors. However, wireless signals such as Bluetooth, tend to be affected by an obstruction, thus creating a non-line-of-sight (NLOS) environment. This paper proposes a statistical technique for improving the accuracy of indoor positioning using BLE technology through detecting obstructions and compensating for signal degradation caused. Several experiments are conducted to observe the obstruction effect on the signal stability, computed in this paper using standard deviation. Results show a lower standard deviation for an NLOS environment. A threshold is suggested at 2.6 dBm to detect a line-of-sight (LOS) environment. The detection accuracy of this threshold is 76.25%; thus, in most cases, the technique will be able to differentiate an LOS from an NLOS environment. Using this technique, positioning in NLOS environments show an average of 1.13 metres improvement compared to positioning without using the technique.