Design And Implementation Of Indoor Positioning System Based On UWB

Ultra-Wide Band(UWB)technology has high precision,low power consumption and strong anti-interference ability.It has Outstanding advantages and higher application potential compared with traditional indoor positioning technology in large logistics warehouses,important personnel equipment storage,rescue search and rescue and large shopping malls.But the UWB technology mainly used in indoors is faced with a more complex positioning environment.In some areas,severe signal attenuation will occur,which will greatly reduce the accuracy and even make the positioning difficult to continue.This paper analyzes and improves the UWB positioning algorithm,at the same time,inertial devices are added to improve the stability and accuracy of the system.After designing the joint positioning scheme and establishing the actual positioning system,verify the positioning effect through simulation and experiment.Based on the technical characteristics of UWB,this paper first analyzes the basic principles of UWB positioning,and determines the data acquisition scheme used in this paper by combining the different acquisition methods of UWB measurement information and the corresponding subsequent processing methods.We discussed the errors in the UWB part and the IMU part of the positioning system to be acquired when acquiring the original measurement information.And designed the corresponding optimization scheme for the antenna delay,clock error and non-lineof-sight error reduction.We also give the mathematical accuracy judgment indicators to provide basis for subsequent simulation experiments.Subsequently,this paper focuses on the positioning algorithm under the UWB positioning model,analyzes the advantages and disadvantages of the Chan algorithm and the Taylor algorithm,and the possibility of synergy between the two,and further proposes a recognition algorithm based on distance residuals to identify the NLOS identification of the positioning system.In order to effectively utilize the measurement information of DW1000 and motion sensor,this paper further studies the joint positioning algorithm.Based on Kalman filter,We give a model of location tracking and design a combined positioning model based on extended Kalman filter for UWB and motion sensor information fusion.Finally,using the Matlab to complete the simulation positioning experiment in the simulation environment,the feasibility and effectiveness of the combined positioning model are verified.After completing the theoretical analysis and design,this paper starts from the actual positioning system,completes the overall design of the joint positioning system from hardware to software,and completes the cooperation of data transmission,acquisition and upload in the UWB control chip;In the solution of the completed attitude,the upper machine outputs the acceleration in each direction of the current geographic coordinate system and converts it to the laboratory coordinate system to remove the gravity acceleration component;finally,the data fusion of UWB and motion information based on extended Kalman filtering is realized in the upper computer.After the experimental platform is built,we collect the actual static measurement information and dynamic measurement information,and compare and analyze the difference of positioning accuracy between the independent UWB measurement system and the data fusion positioning scheme.It proves that the joint positioning algorithm designed in this paper helps the accuracy improvement,and at the same time builds an actual positioning system that can be applied and positioned in the indoor environment.