Study On Localization Problem Of Wireless Sensor Network With Noises

Since the 21 st century,the continuous progress of computer,microelectronics and communication technology have led to the rapid development of wireless sensor networks.In the wide application of wireless sensor networks,estimating the position of each sensor node is often a necessary part.Around the localization problem,many domestic and foreign scholars from different fields have designed a large number of localization mechanisms and algorithms.However,as wireless sensor networks are usually deployed in complex environments,the existing algorithms may have some problems in application,such as loss of accuracy,weak anti-noise ability and so on.This paper considers the localization problem of sensor networks with noises,and designs localization algorithms with high robustness.In this paper communication and measurement noises are analyzed,and through the treatment of these two kinds of noise,localization algorithms with corresponding noises are developed.Based on the analysis of the communication noise in terms of quantization error in digital communication,a dithered quantization method is provided.Using the knowledge of random theory,the paper provides a distributed localization algorithm called ECHO-CN which based on the barycentric coordinate and the existing algorithm named as ECHO.Future,the mean square convergence and almost sure convergence under different parameters of this algorithm is studied,combined with rigorous theoretical proof.The measurement noise is studied in the second part of this paper,and an unbiased distance estimator is constructed.Under the large number theorem,the estimation of distance between nodes converges to the true value gradually.Also based on the barycentic coordinate,combined with the distance estimation mechanism,this paper then develop the ECHO-MN algorithm with the consider of measurement noise.During the analysis of this algorithm,the proof of the almost sure convergence is also given,and draw the conclusion that its convergence rate depends on the rate of the large number theorem.Finally,with the consideration of both communication and measurement noises,the ECHO-CN and ECHO-MN are combined to form the algorithm called ECHO-CMN.For the algorithm proposed in this paper,in addition to the rigorous proof of convergence,some proper simulation examples are given to verify the correctness of the analysis results.