Research On Information Source Localization Technology Based On Distributed Monitoring Nodes

As the progress of wireless communication, various wireless communication based services are emerging. Location information is one of the important services provided by wireless communication. However,all kinds of location information acquisition methods mainly focus on the positioning of the receiver. A wide variety of fake base station, illegal information source appear with the increasing complexity of space radio signals. Distributed monitoring network is the development direction of future radio monitoring system. In this thesis, the source localization technology based on distributed monitoring node is studied.The method of source localization has many kinds of methods such as direction finding, distance measuring, and mixing location and so on.Positioning method based on propagation time difference has the advantages of low requirement for measuring equipment, high accuracy of positioning. In recent years, the location algorithm based on Geographical fingerprint which has a high positioning accuracy is widely used in indoor environment. This thesis does some research on several aspects.First of all, for the location method based on the propagation time difference, the traditional time difference estimation method has poor performance under low SNR and correlated noise. An adaptive time delay estimation method based on higher-order cumulant is proposed in this thesis. Furthermore, a Non-line-of-sight path processing algorithm is proposed to improve the location accuracy. In addition, according to the WCDMA system, the specific scheme of time difference acquisition and base station division is analyzed. Finally, aiming at the shortcomings of the method based on propagation time difference, the feasibility of the method of fingerprint location in outdoor complex environment is explored through the field measurement.