Research On Technology Of Seamless Positioning Based-on UWB/GNSS/MIMU

In recent years,indoor positioning technology has become a hot topic in the field of navigation,and seamless positioning technology is the key technology of the engineering application.Based on the navigation and positioning technology of UWB,GNSS and MIMU,this thesis studied seamless positioning.The specific work is as follows:1,The application of GNSS/MIMU integrated navigation technology in outdoor environment was researched.The loose integrated navigation algorithm was verified by simulation data and real car test.The experimental results show that in the complex urban environment the positioning continuity of integrated navigation module is 99.59%,which 75.68% is less than 3m.At the same time,when the satellite signal lose lock in a short time(about 60s),the navigation module can still provide positioning results about 3m.2,The application of UWB/MIMU integrated navigation technology in indoor environment was researched.The DW1000 chip and the MTi-G-700 module were respectively used as UWB and MIMU data acquisition equipment.The car experiment was carried out.The experimental results show that the UWB/MIMU integrated navigation algorithm can make the positioning accuracy better than 2m,can effectively reduce the jumping and missing of UWB positioning results and make the trajectory more stable and smooth.3,Aiming at the problem of the poor accuracy and reliability of GNSS/UWB positioning results caused by the interference of GNSS and UWB signal.This thesis proposes a integrated navigation algorithm based on UWB/GNSS/MIMU.Using GNSS pseudo range equation and UWB distance equation form an overdetermined equation system,which is composed of a group of weighted least square solutions,and then,the loose combination of equation solutions and the location of the MIMU are calculated.Simulation results show that the method can improve the accuracy and reliability of positioning results,providing a new idea to indoor and outdoor seamless positioning.4,Studying the handoff algorithm in seamless positioning.This thesis referred vertical handoff theory in communication profession,proposes a vertical handoff algorithm based on cost function in seamless positioning and added delaying level,residence time,movement tendency in the algorithm,in order to improve the effectiveness of the algorithm.Finally,the simulation results show that the proposed algorithm can effectively reduce the ping-pong effect.