High accuracy VLC indoor positioning system with differential detection

Recently, several positioning systems based on visible light communications (VLC) have been proposed, and most of them are based on received signal strength (RSS) because of its simplicity and high accuracy. In order to improve the accuracy further, a differential detection-based positioning algorithm is proposed. It can reduce positioning instability caused by light intensity fluctuation and the area outside the light-emitting diode (LED) cell can also be positioned. Experimental results show that the proposed method can improve the positioning accuracy from 10.0 to 4.0 cm and reduce the standard deviation from 9.0 to 2.5 cm. Meanwhile, the positioning accuracy outside the cell can reach 10.0 cm or less.