Research On High Precision Acoustic Indoor Localization Based On Time Of Arrival And Frequency Estimation In NLOS Environment

Acoustic localization technology has good compatibility with intelligent mobile terminal,high localization accuracy and low cost,therefore,It has broad prospects in the field of indoor localization.However,Non-line-of-sight(NLOS)phenomenon is common in indoor environment,so it is difficult to achieve high-precision localization.Therefore,In this paper,the frequency shift invariance of Hyperbolic Frequency Modulation signal is used.The key technologies are thoroughly studied from localization technology in complex NLOS environment and new methods are proposed for indoor localization and navigation.The main content of this thesis is summarized as follows:(1)An accurate range and speed estimation method is proposed by using a compound HFM signal,and the specific modulation method of the compound HFM signal is given by avoiding sound pollution and concerning the spectrum leakage,which is induced by truncation effect.Time delay and Doppler factor estimation using Generalized Cross Correlation method.The experimental evaluation results show that: the probability of range estimation errors less than 0.1m and 0.05 m are 90% and 80%,respectively;the probability of speed estimation errors less than 0.1m/s and 0.09m/s are 88% and 80%.(2)A novel localization method based on TOA(Time of Arrival)and FOA(Frequency of Arrival)of acoustic signal is proposed by using particle filtering.Obtaining NLOS information by unsupervised recognition method,Particle filter is used to filter NLOS information,time of frequencu and frequency of arrival estimated values are fused.In order to achieve the goal of localization.The experimental investigation verified that only 2 LOS acoustic signal is needed for 2D positioning,And while the confidence probability is 90%,the localization error is 0.35 m.