Research On Optimization Strategy Of Location Management In Mobile Computing Environment

Compared with the fixed communication network, the major advantage of mobile communication system is removability. The mobile users can communicate conveniently with each other in a wide range of areas and keep corresponding continuity though the mobile services. With the continuous development and extensive applications of technologies in the fields of communication and computer network, mobile computers can access to kinds of networks at any time and anywhere to get the information they wanted in the near future. The special distributed computing environment is called mobile computing. The mobile computing is considered as one of the most influential technologies in the future and has become the hotspot of research.The location management of mobile computing environment is an important part of the system resources management which is responsible for tracking and locating the mobile terminals and setting up an available connection for mobile user's calling. Then the location management can be divided into two basic operations: paging and updating. The former relates to the calling arrival rate;the latter refers to the movement rate of mobile terminals. The cost on the paging and updating constitutes of the main expense of the system resources, including signals exchange between mobile stations and base stations, wireless network bandwidth, database resource and so on.At present most of research on location management focus on optimization of database configuration and shorten transmission of signal, reduce database updating, decrease paging delay etc. Recently many studies concentrate on the dynamic strategy, which design location area according to the move characteristic of individual. This kind of design method needs high terminal process capability and signals interaction between users and the networks, that isn't suitable for the actual design of mobile communication system. So the emphasis of the location management research isexploring a new way that is not only based on the user individual move characteristic, also fit for the project application.Regarded the national natural science program, the research of mobile decisive theory and its support system, as its research background, this dissertation proposed a new fuzzy method used to achieve location management in mobile computing environment. First the paper introduces PCS network structure in mobile computing environment and the conception of location management in PCS network. Then a Gauss-Markov model was adopted as the mobility pattern to predict the speed and locations of a mobile user. On a basis of the real-time prediction of the user's movement speciality, the paper puts forward a new fuzzy design method of location area for a large number of mobile subscribers which have different move characteristics and communication situations, as well analyzed the influences of the speed and calling arrival rate on the design of location area through fuzzy modeling and simulation. Finally the paper realizes the optimization design method of location management strategy including updating and paging arithmetics. A new location management optimizationstrategy based on fuzzy design of location area explained in the paper was simulated by MATLAB. Compared with other common dynamic methods, performance of the new way is better on some conditions, which can get more reduction of system resource cost if forecast the movement of mobile user more accurately.It should be pointed out these theories, methods and results introduced in this dissertation are quite useful in such research areas as location updating and paging based on predicted location information in mobility management, which aims to improve mobility management performance, reduce signal instructions and increase the effective capacity of the system, the improvement of current mobile communication networks, and the design of the next generation mobile communication networks. At the same time, fuzzy design theory is applied to location management in mobile computing environment, which is helpful to the research of exploring the network management.Hu Shui (Control Theory and Control Engineering)Supervised by Li Demin...