Desigh And Implementation Of Tracing System Server Based On Ubiquitous Network

In recent years, with the rapid development of intelligent wear equipment, chip-making technology and Internet communication technology, the concept of "ubiquitous network" has been mentioned more and more. The ubiquitous network will realize the seamless interconnection of information space and physical space. In the network to the ubiquitous, all-encompassing, omnipotent for the three basic features, making people and people, people and things, objects and things can be smooth communication. The basic idea of the ubiquitous search system is through the mobile terminal and intelligent wearable devices to work together, with the user’s social circle and big trajectory data information to search and rescue the lost elderly or minors, with the means of technology, fully integrated Social mutual aid resources and the implementation of individual emergency relief.This thesis’ research based on the ubiquitous search system, this paper aims to search and search for the lost people as the specific application scenarios.The whole paper focous on the design and implementation of the server functions. According to the application situation and requirements, the server functional framework is divided into positioning calculation module, trajectory prediction module, task management module, equipment management module and the user management module. This paper studies and realizes a whole set of wireless location scheme combining GPS positioning and low power Bluetooth technology. In the positioning of the target device, a plurality of mobile terminals receive the near-field signal from the target device for positioning. The distance between each mobile terminal and the target device can be obtained according to the RSSI distance propagation model in the data acquisition stage. In the position calculation stage, Group positioning data simultaneous equations, the application of least squares method for geographical location. In this paper, a moving object trajectory prediction method based on CRFs (conditional random fields)is proposed for trajectory characteristics of moving objects. The method includes moving space trajectory space segmentation and segmentation processing, CRFS-based trajectory Forecasting model. The trajectory prediction module can direct the searching of the key geographical areas during the search of the target device, reducing the time cost of the searching device and improving the searching efficiency.Firstly, the paper introduces the related theory and technical background of ubiquitous network and ubiquitous search system, and then designs suitable localization algorithm and trajectory prediction algorithm according to the system application scenario. Secondly, the demand analysis and detailed design of the ubiquitous search system server are carried out. And then the server location calculation module,trajectory prediction module and other functional modules are described in detail and implemented, and the system server side, respectively, unit testing and integration testing to ensure that the server-side to meet the demand. In the end, the paper is summarized and the future work is discussed.