In this paper, a calibration method based on a two-step extended Kalman filter (EKF) is proposed. Firstly, the four vertex positions of a rectangle in the environment are calibrated. Specifically, in the first stage the initial position states of all anchor nodes are obtained using a rough localization method. In the second stage, the first and second step EKFs are used to obtain the real-time state of the measured target and all anchor nodes. The state estimation of all anchor nodes is achieved by employing the iterative process of the two-step EKF. The effectiveness and stability of the proposed algorithm are verified by simulations and experiment.

中文翻译：

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基于两步扩展卡尔曼滤波的室内环境锚点位置标定方法

本文提出了一种基于两步扩展卡尔曼滤波器（EKF）的标定方法。首先，校准环境中矩形的四个顶点位置。具体地，在第一阶段，使用粗略定位方法获得所有锚节点的初始位置状态。在第二阶段中，第一步和第二步EKF用于获取被测目标和所有锚点的实时状态。通过使用两步EKF的迭代过程，可以实现所有锚节点的状态估计。通过仿真和实验验证了所提算法的有效性和稳定性。