Human Position Estimation Using Wi-Fi CSI Variations

The demand for indoor monitoring systems has increased owing to the growing elderly population. Cameras are commonly used for indoor monitoring, but the field of view is limited. In this paper, we propose a human position estimation method using Wi-Fi within an observation area without complex calculations. Experiments were conducted in an 18 m2 observation area inside a gymnasium, where a single access point (AP) was placed in three different positions, and 12 receiving antennas were installed around the perimeter of the observation area. Human positions were estimated on the basis of channel state information (CSI) variations, specifically the moving variance of the CSI amplitude component measured at each receiving antenna. The estimation error was evaluated by comparing the results to actual positions measured by LiDAR.