Design And Implementation Of Fused Indoor Positioning System Based On MEMS Sensors And VLC

At present,with the rapid development of the Internet of Things and new mobile devices,location services have become a basic service requirement no matter whether it is outdoors or in a complex indoor environment.Visible light positioning(VLP)technology based on Visible Light Communication(VLC)has attracted much attention in the field of indoor positioning due to its low cost and high precision.But there are still many problems.In the field of pedestrian indoor positioning,the assumption that the receiver is placed horizontally is difficult to meet,and the observations obtained by the Photodiode-based VLP system are easily blocked by the pedestrian's body;The positioning method is limited by the resolution and angle of view of the camera,and the actual application conditions are harsh.In view of the above problems in the current VLP system,A low-cost,high-precision,highrobustness combined positioning method based on PD,camera and MEMS inertial sensors is proposed in this paper.A Lambertian model correction method is designed to correct deviation between theoretical Lambertian coefficient and actual.And the positioning location when the receiving end is not horizontal is solved by the modified Lambertian model.Then,the method of acquiring observations from the camera and MEMS inertial sensors when the receiving end is not horizontal is designed.Finally,in the fusion positioning algorithm part of the VLP system,two tightly coupled fusion architectures are designed,namely a single filter tightly coupled architecture(SEKF)and a double filter tightly coupled architecture(DEKF),which combines observations based on PD,camera and MEMS inertial sensors to obtain high-precision and high-robustness positioning results.In this thesis,a real experimental environment is built and dynamic experiments are conducted.The experimental results show that in the presence of a random inclination angle of less than 15 degrees at the receiving end,the positioning error of SEKF is 21.58 cm,and the positioning error of DEKF is 18.02 cm.Compared with the PD-based positioning method,the average positioning accuracy is improved by 30% ? 40%.The combined positioning method based on PD and camera proposed in this paper can effectively achieve low-cost,high-precision,high-robustness dynamic indoor positioning.