Fig. 1. Overall block diagram of visible light indoor positioning system

Fig. 2. LED drive circuit

Fig. 3. Flow chart of coding RTL

Fig. 4. Singal waveform of LED

Fig. 5. Effects of LED-ID light stripe code under different exposure. (a) 1/500; (b) 1/1000; (c) 1/2000

Fig. 6. Effects of LED-ID light stripe code under different sensitivity. (a) 1000; (b) 200; (c) 50

Fig. 7. Effects of light stripe code at different frequencies^[11]. (a) 1500 Hz; (b) 2000 Hz; (c) 3000 Hz

Fig. 8. Effects of light stripe code under different duty cycle. (a) 25%; (b) 50%; (c) 75%

Fig. 9. Effects of light stripe code under different distances. (a) 10 cm; (b) 20 cm; (c) 30 cm

Fig. 10. Selection of duty cycle column pixels

Fig. 11. Column pixel grayscale

Fig. 12. Support vector

Fig. 13. Three-dimensional diagram of LED-ID recognition

Fig. 14. Side view of LED-ID recognition

Fig. 15. Transformation relation of coordinate system

Fig. 16. System model of proposed location algorithm

Fig. 17. Different situations of rotation angle φ

Fig. 18. Light distribution map

Fig. 19. Three-dimensional diagram of positioning results

Fig. 20. top view of positioning results

Fig. 21. Distribution of positioning error