UWB Indoor Positioning System Calibration Method Research

After traditional positioning technology development,UWB technology with its high precision,high immunity,high penetration,high security,low power consumption and other characteristics gradually displaces the position of Bluetooth,Infrared,WiFi and RFID technology and becomes the hot point on indoor positioning.At present,the indoor positioning system based on UWB technology has been successfully applied in prison management,power station patrol line and virtual reality.The positioning accuracy can reach decimeter level under certain constraint conditions.However,with the positioning accuracy improvement,most enterprises and manufacturers still use their own criteria to measure the accuracy of the product,for the UWB indoor positioning system calibration system does not have a unified standard.In this thesis,by analyzing the error sources of the UWB indoor positioning system,a complete process of calibrating the UWB indoor positioning system is proposed.The error of the UWB indoor positioning system is calibrated and the effect of the positioning accuracy is improved for the future of the industry and the calibration standard.The main work of this thesis is as follows:1.The thesis summarizes the development of indoor positioning system and researches on UWB high precision indoor positioning system development status and calibration technology,then illustrated the significance and needs of the UWB indoor positioning system calibration work.2.The error of the UWB indoor positioning system in the process of distance measurement is studied,and the objectivity and non-negligibleness of the error are elucidated.The time synchronization error,the antenna phase center error and the base station ranging error are analyzed and modeling.Tthe feasibility of the model is also studied.3.The error model is used to calibrate the error.In the calibration of time synchronization beacon error,a multi-antenna mutual calibration method is proposed to test the antenna time delay.The antenna model is constructed by 3D laser scanning modeling to extract the axis and the vertex to calculate the center of the antenna phase.The error of the ranging section is calibrated by referring to the total station plus multiplication method.4.The PDOP value simulation is used to analyze the base station layout of UWB indoor positioning system.The static positioning accuracy of the system is tested and the dynamic positioning accuracy of the system is tested based on the laser tracker.The fitting algorithm is used to fit and evaluate the dynamic trajectory.