Research On Wireless Location Algorithm In NLOS Environment

With advances in single-chip microcomputer systems,wireless communication systems,and sensors,wireless sensor networks(WSNs)have taken up an important position in the field of data sensing and data acquisition because of their advantages of low cost,simple implementation,strong stability.There have been many studies on the WSN location problem in the NLOS environment,but few literatures have discussed the identification and suppression of NLOS measurements from the perspective of recognizing the recovery from localization failures caused by NLOS measurements,and the 100% discrimination NLOS measurement is Difficult to do.The main content and work done in this article are as follows:(1)Introduce the related concept of WSN,study the commonly used ranging technology,positioning model and NLOS error model in WSN,focusing on the various positioning algorithms of WSN and NLOS error suppression.The advantages and disadvantages of the algorithm and applicable conditions.(2)In order to solve the problem that it is impossible to completely pre-identify the NLOS measurement and thus cause positioning failure,a hybrid particle/FIR localization algorithm(HPFF)based on positioning failure recovery is introduced.The distributed HPFF algorithm(DHPFF)for identifying NLOS,and thoroughly discusses the root cause of the effective model-based failure diagnosis method for HPFF in the case of particle collection depletion.The simulation results show that the effectiveness of HPFF under conditions of particle collection depletion,the effectiveness of DHPFF in a single NLOS environment,and complete failure in multiple NLOS environments.(3)Starting from the principle of particle filtering,the reasons why DHPFF can't be located in multiple NLOS environments are analyzed in depth.a positioning failure diagnosis method based on predictive particles is proposed to identify NLOS.Based on this,the decision-making process of DHPFF was improved,which made it possible to distinguish effectively the set failure caused by particle set depletion and NLOS measurement.Simulation experiments show that the improved DHPFF and DHPFF have the same performance in a single NLOS environment.In a multi-NLOS environment,the improved DHPFF has good performance and solves the problem that DHPFF cannot be located.