A Simultaneous Visible Light Positioning and LED Database Construction Scheme

Visible light positioning (VLP) is endowed with high accuracy in indoor scenarios. However, the positioning algorithms require plenty of beacon light-emitting diode (LED) coordinates stored in databases, which are expensive to obtain by manual measurements. To circumvent such laborious efforts, we propose a two-step automatic scheme for simultaneous VLP and LED database construction. Specifically, in the first step, a receiver with a photodiode (PD) array samples the optical signals from few benchmark LEDs to locate itself. In the second step, the receiver estimates the unknown beacon LED coordinates through its own locations and the beacon LED signals. For the proposed two-step scheme, we derive closed-form error expressions for the beacon LED coordinates to evaluate the benchmark LEDs' arrangement and the sampling places. Simulation results agree with the analytical error expressions and reveal that the proposed scheme can achieve centimeter-level accuracy with reasonable transmit powers. Experimental results from the hardware platform verify the feasibility of the scheme. The proposed scheme can circumvent laborious manual measurements and allow the LED database to "grow" while the receivers wander and more receivers enter.