Optimization And Improvement Of Centroid Localization In Wireless Sensor Networks

Localization is one of the core problems in wireless sensor networks,the study and development of the localization is very important,especially in some special scenarios,such as the forest fires and disaster rescue.This paper studies the localization technology,emphasis on the study of the non-ranging based centroid localization algorithm,and an improvement of existing research on the algorithm is carried out.The main work and innovations in this paper are as follows:(1)The localization technology and the research status of the technology at home and abroad are studied,the specific principles of the ranging-based localization algorithm and the non-ranging based localization algorithm are discussed,and then,several indicators for evaluating the performance of the algorithm are given.Finally,the challenges faced by the current non-ranging based localization algorithm are briefly introduced.(2)In order to solve the issue of traditional centroid localization algorithm's localization accuracy,a weighted centroid of mass algorithm based on weight correction is proposed.The improved algorithm converts the RSSI data received by blind nodes into distance,then calculates the negative square of distance ratio as an mend weight,and then estimates the coordinate of blind nodes.The simulation results indicate that comparison of general centroid localization algorithm and the general weighted centroid localization algorithm,the proposed weighted centroid algorithm can greatly improve the accuracy of positioning.(3)In order to solve the issue of unsteadiness of RSSI value,a weighted Gauss filtering algorithm based on weight correction is proposed.First of all,the RSSI value is preprocessed,then the preprocessed RSSI value is Gaussian filtered,and finally the RSSI value is averaged and weighted to obtain the final RSSI value.The simulation results indicate that the improved algorithm reduced the error of ranging to a certain degree.In addition,we combine the improved algorithm in ranging stage with the improved algorithm in location stage to make a better positioning accuracy than other enhanced algorithms.