Research On Personnel Trajectory Tracking Method Based On UWB In Nlos Environment

Ultra-Wideband(UWB)is a communication method that uses pulses with extremely short time intervals(less than 1ns)without using a carrier.Because UWB itself has the advantages of high positioning accuracy and simple operation,ultra-wideband positioning is more and more widely used in current production and life,and is widely used in academic and industrial production.Therefore,this thesis focuses on the UWB positioning that is more in line with the actual scene.The current issues of UWB positioning in terms of the number of base stations,equipment costs,and positioning accuracy are discussed further.The main contributions and innovations of this paper are as follows:(1)An improved Kalman filter algorithm in non-line-of-sight(NLOS)environment is proposed.It uses the maximum likelihood estimation algorithm to iterate to eliminate the influence of NLOS on the positioning algorithm to the greatest extent.Clock synchronization.Through experimental verification,it is found that this method improves the positioning accuracy and stability in the whole.(2)The Bayesian Compressed Sensing mechanism is introduced.Then,the 3D perception is used to model the human body,analyze the transmission law of crawling waves on the human body and recover the acquired UWB crawling wave signals by Bayesian Compressed Sensing.Combining with maximum likelihood estimation and the iterative approximation algorithm,the label position is determined.This paper proposes a method using Bayesian compressed sensing to eliminate the effects of creeping waves,and verifies that the algorithm has better performance on signal recovery through actual experimental scenarios.(3)A trajectory tracking algorithm based on the least square method is proposed.Firstly,the non-line-of-sight signal is identified through the estimation of the channel model,and the second is based on the TDOA algorithm to use the direct path component(Dreact Path,DP)to calculate the time difference between the sender and receiver.Then,the N-WLS algorithm is used to eliminate the time gap between the positioning tags due to environmental factors and the time gap causing by the sending and receiving ends;by determining the position of the tags at different moments to describe the trajectory of the tags,a weighted least square method is used to realize the trajectory tracking method N-WLS in the NLOS environment.By building an actual experimental platform and analyzing the experimental results,the trajectory tracking method for people in a non-line-of-sight environment based on UWB improves the accuracy of trajectory tracking,improves the positioning effect,and achieves fewer base stations,shorter base station tag distance,lower equipment cost and higher positioning accuracy,etc.The expected positioning target is achieved.