Multipath Mitigation for RSSI-Based Bluetooth Low Energy Localization

Multipath fading poses a great challenge in indoor wireless positioning. In this paper, we propose a 2-stage multipath mitigation technique which consists of RSSI filtering and received signal strength indicator (RSSI) combining methods. First, a low-complexity weighted average filter is proposed in the filtering stage. Then, a space diversity, where multiple Bluetooth Low Energy (BLE) tags are attached to the object being tracked, is presented in the combing stage. Here the signals from multiple tags are combined to provide signal stability. Measurement results showed that an overall position estimation error of around 1.5 m can be achieved by using the proposed technique with BLE anchor optimization.