An UWB-based indoor coplanar localization and anchor placement optimization method

Ultrawideband (UWB)-based localization systems are appropriated for human and vehicle tracking because the time-of-flight between UWB devices can be accurately estimated. A moving UWB embedded target can be located by the anchors whose positions are set in the initialization step. Considering that some areas are unreachable or dangerous for humankind or some urgent tasks make it impossible to set the position for anchors manually. Hence, we propose a coplanar localization method for one-side-open areas, which is easy for deploying. In this method, the coordinates of the inside node can be estimated by the coplanar outside anchors that are attached to an outside window and are easy for calibrating. However, optimizing anchor placement is still a critical challenge that affects localization performance and is essentially NP-complete. To improve the localization accuracy, we propose an anchor placement optimization method that is based on utilizing the genetic algorithm and minimizing the Cramer-Rao lower bound. Finally, field experiments are conducted, and a thorough comparison confirms the efficiency and effectiveness of the proposed method.