Improving Wi-Fi indoor positioning based on matching visibility with virtual simulation

Wi-Fi is vulnerable to non-line-of-sight (NLOS) propagation and multipath effects in indoor positioning. This paper proposes a novel access point (AP) visibility matching method for Wi-Fi round-trip-time (RTT) ranging, aiming at reducing positioning errors in complex NLOS indoor environments. This method identifies NLOS signals to determine observation visibility based on the RTT and received signal strength indicator (RSSI). This method also projects the floor plan onto the polar coordinate system to derive simulation visibility. By comparing the consistency between simulation and observation visibility, the method pinpoints where users are most likely located. Experimental evaluations demonstrate that the proposed method achieves positioning accuracy comparable to fingerprinting, without the need for extensive pre-work.