Research On Indoor Positioning Technology Of Wireless Sensor Network Based On Received Signal Strength

With the development of science and technology,the demand for indoor positioning in all walks of life is increasing day by day,and the requirement for indoor positioning accuracy is also gradually improved.In this paper,the indoor positioning technology of wireless sensor network based on receiving signal strength is studied in depth with the aim of improving indoor positioning accuracy.The main work of this paper is as follows.1.In view of the errors in the ranging stage,RSSI preprocessing is adopted to obtain smooth and accurate RSSI as the basis of distance estimation.Experimental results show that RSSI pretreatment can effectively improve the ranging accuracy and positioning accuracy,and the average positioning accuracy is improved by 33.98%.In view of the limitations of the traditional weighted centroid location algorithm with single distance as the weight,a weighted centroid location algorithm using distance logarithm as the weight is proposed to calculate the unknown node coordinates,so as to reduce the influence of ranging error on the final location coordinates.The experimental results show that the error of 75% localization results is less than0.8 m by using the logarithmic weighted centroid localization algorithm.2.In the process of using the weighted centroid positioning algorithm,the circle may not intersect the circle.In order to improve the fault tolerance of the localization algorithm,an improved distance correction localization algorithm was proposed.The measured distance factor was used as the weight to correct the radius of the two circles,and the radius ratio of the two circles before and after the correction was guaranteed to remain consistent.Experimental results show that the average positioning accuracy of the modified weighted centroid positioning algorithm is 16.16% higher than that of the unmodified weighted centroid positioning algorithm.Combined with RSSI pretreatment,the average positioning accuracy of the logarithmic weighted centroid localization algorithm with distance correction is 45.57%higher than that of the traditional weighted centroid localization algorithm.3.In order to further improve the positioning accuracy,the Bayesian filtering method is proposed.On the basis of the initial coordinates obtained by the log-weighted centroid location algorithm with distance correction,the coordinate values are modified according to the subsequent updated ranging results to obtain more accurate positioning coordinates.Experimental results show that the positioning accuracy of the Bayesian filtering algorithm is63.73% higher than that of the traditional weighted centroid positioning algorithm.