Research On Modeling And Algorithm Of Indoor Moving Target Positioning System

Wireless localization has always been an significant research topic on the applications of tracking,navigation,business and public safety,etc.And it has been widely concerned by domestic and foreign scholars.According to the different positioning scenarios,it can be divided into the outdoor positioning and the indoor positioning.For the outdoor positioning,a variety of the Global Navigation Satellite Systems(GNSS)have been broadly used,which can provide sufficient positioning accuracy to meet the requirements.However,the universal solution has not been found due to the attenuation of satellite signals,the shadowing by obstacles and non-line-ofsight(NLOS)propagation.Especially for the dynamic positioning of indoor moving target,improving the positioning accuracy and performance has always been the focus of the subject researches.Mostly,they focus on the optimization of existing positioning/tracking algorithms,the data fusion based on multiple positioning technologies/methods,and the auxiliary positioning based on motion data,etc..However,there are relatively few studies to analyze the impact of specific strategies on positioning accuracy from the aspect of the practical application.Therefore,aiming at improving the positioning accuracy and performance under mobile conditions,this paper studies the positioning of moving target based on time-division strategy in complex indoor environments.The specific research work is as follows:Firstly,aiming at the dynamic positioning problem of moving target under indoor environments,the system model based on time-division strategy of moving target positioning is proposed.Specifically,the distance model used for positioning is remodeled by taking the time-division and movement characteristics into consideration,making it more appropriate for the practical application.And it is laying the foundation for subsequent research.Secondly,based on the above-mentioned improved distance model,the positioning algorithm is coupled with two system parameters including the velocity of moving target and the slot length of the time-division strategy.And the least squares(LS)algorithm,the Taylor algorithm and the extended kalman filter(EFK)algorithm are optimized and improved.Then the I-Taylor algorithm and the I-EKF algorithm are adopted to calculate the position of the target to be localized.Finally,the numerical simulation based on MATLAB and the moving target positioning experiment in indoor actual scenario are carried out.The simulation and experimental results show that the improved algorithms are robust under different conditions of system parameters.And compared with the unimproved algorithm,it can reduce the positioning error to a certain extent and improve the positioning performance of the system,which verify the effectiveness and robustness of the improved algorithms.Furthermore,in order to further improve the positioning accuracy in real test scenario,the impact of error caused by different ranging schemes is analyzed.