Accuracy Analysis of UWB RTLS in Multipath Environment

Ultra-wideband (UWB) is a radio technology based on the IEEE 802.15.4a and 802.15.4z standards that enable highly accurate measurement of the Time of Flight (ToF) of the radio signal, leading to centimeter-level distance accuracy measurement. UWB has revolutionized real-time location (RTL) with its high-accuracy of a few centimeters positioning capabilities in both indoor and outdoor environments. However, the accuracy may degrade if there are multipaths and obstructions between the devices that hinder the line-of-sight (LOS). Since GPS signals are not available in indoor environments, UWB has significant benefits over GPS for indoor navigation. In this paper, we have analyzed UWB position accuracy results from an empty room (low multipath) and a normal office room with a multipath environment. We have also analyzed the response of CIR (Cumulative Impulse Response) based on Preamble Length (PL) and Pulse Repetition Frequency (PRF). The CIR data helps to correctly detect the "First Path" peak to compute range measurement even if there are multiple stronger signal peaks.