The Study Of Mobility Management In The Ultra Dense Network And Implementation Of Verification System

With the growing needs, the wireless network is facing more and more challenges. In order to meet the demand of the high data rate, ultra dense network has become an important method to solve this problem. In the ultra dense network, the traditional mobility management algorithm has been unable to adapt the development of the network, and how to solve the problem of mobility management has become a huge challenge for the development of the future network.After the existing mobility management technology is introduced, the following three aspects are studied:1) Based on characteristics of the ultra dense network, the birth death model is used to model the network and the characteristics of the network are analyzed. Based on the birth death model, a network switching algorithm with variable protection channels is proposed. Considering the new calls and handoff calls, the number of the protection channel is changed due to the prediction of equipment switching. Finally, the simulation results show that it can effectively reduce the blocking rate and increase the channel utilization.2) To solve the mobility management problems in ultra dense clustering network, this paper presents a handover management algorithm that adjusts the hysteresis margin according to the status of the terminal equipment. In this algorithm, the handover procedure is divided into pre-handover and official handover after clustering small base stations. The pre-handover helps to select the best target cell, complete resource reservation and pre-authentication. During the official handover, hysteresis margin of the handover threshold is adjusted according to the speed of the device. Simulation results show that it can effectively reduce the handover delay and probability of handover failure.3) The verification system of terminal side mobility management is designed and completed. In the system, the controller continuously broadcasts its information. After the terminal finds the broadcast information automatically, it finishes login and connection with the controller. Meanwhile, the entire process of mobility management is displayed. Through the design of each part of the system, the development of each module is implemented. After the code is transplanted to the ARM development board, the system is debugged and the running process is demonstrated. Based on the result, the system realizes the registration and access to the controller, which reflects the mobility management process in wireless networks. At last, the initial design goal of the system is achieved.