Fig. 1. System hardware overall architecture diagram

Fig. 2. Schematic diagram of ranging

Fig. 3. Three-side positioning under ranging errors. (a) No-intersection; (b) intersection, and the intersection area is too large

Fig. 4. Distance distribution of base station

Fig. 5. Adaptive three-sided positioning correction process. (a) When the intersection area of three circles is too large; (b) when the three circles do not intersect

Fig. 6. Solution of label position

Fig. 7. Simulation position estimation diagrams. (a) Weighted centroid method to solve the label position map; (b) adaptive three-sided positioning algorithm to solve the tag position

Fig. 8. Distance between the estimated location and the actual location for different labels

Fig. 9. Layout of the base station

Fig. 10. Positioning renderings of each algorithm. (a) Least square method; (b) centroid method; (c) weighted centroid method; (d) adaptive three-sided localization algorithm