Passive UWB TAG Localization based on Reference Node

Ultra-Wideband (UWB) technology has become a popular positioning technology due to its high bandwidth and strong anti-interference capabilities. However, the power consumption and standby time of UWB tags remain limiting factors for its application. While passive tags significantly reduce power consumption, they perform poorly in precise Two-Way Ranging (TWR) schemes, posing challenges for high-accuracy positioning. To address this issue, we propose a positioning scheme that combines Time Difference of Arrival (TDoA) and angle measurements under passive tags. Specifically, we design a wireless clock synchronization scheme based on reference node to solve the base station clock synchronization problem. By creatively employing data fitting methods to estimate clock drift, our test results demonstrate that this scheme can achieve a median positioning accuracy of $\mathrm{0 . 1 5 m}$ in area of $\mathrm{3 m} * \mathrm{3 m}$ and $\mathrm{0 . 8 6 m}$ in area of $\mathrm{4 m} * \mathrm{1 5 m}$.