3DLoc: A Non-Line-of-Sight 3D Indoor Localization System in Wireless Sensor Networks

Indoor localization systems in wireless sensor networks (WSNs), such as WiFi BLE, are still not widely adopted despite years of continuous research. One possible impediment is that many prior systems perform worse in non-line-of-sight (NLoS) indoor scenarios than in line-of-sight (LoS) scenarios or even fail to work. Nevertheless, realizing localization in both LoS and NLoS scenarios is indispensable for a viable system working in indoor environments. Since existing state-of-the-art solutions mainly aim to localize a target in LoS indoor scenarios, we present 3DLoc that uses multipath channel parameters to achieve 3D localization with a single AP in indoor NLoS scenarios. 3DLoc introduces deployable and simple custom-designed radio relays to assist localization, which can receive signals from the target and forward them to the AP in NLoS scenarios. Field trials conducted in a real NLoS scenario show that our system achieves a median 3D localization accuracy of 86 cm with a uniform circular array (UCA) in NLoS conditions.