Performance Analysis And Key Technology Research On Ultra Dense Networks (UDN)

From the first generation of analogical cellular mobile communication systems to the fourth generation mobile communication, the radius of cells of the mobile communication network is constantly narrowing and the density of cells is constantly increasing. The densification mechanism of cells has brought more than one thousand times for the mobile communication network capacity gain. In the research of 5G, we will further densificate the cells and formate the ultra dense network (UDN).In recent 20 years, the intelligent terminal and the number of connections increase sharply, wireless traffic grows with ten thousand times. The popularity of intelligent terminal and the vigorous development of mobile applications, urge the mobile Internet present an explosive growth. The Internet of things faces a variety of business applications and presents a diversified development trend, its ubiquitous characteristic becomes to come out. Existing macro station deployment scheme has been unable to meet people’s increasing demand for cell covering of network capacity, so the development of ultra dense network is imperative.Firstly, the thesis reviews the background of ultra dense network, presents research situation and the significance of UDN, introduces the small cell concept imported from 3 GPP LTE Release 12, and then gives the ultra dense network from the existing small cell technology of LTE-A. The system level simulation platform is built with C++ language. The design and implementation of the simulation platform is discussed in detail. Secondly, based on the simulation platform, simulation for Scenario 1,2a and 2b under different scenarios of Full buffer and File Transfer Protocol are conducted and analyzed. A variety of receiver schemes are designed and an optimized scheme on the basis of ideal channel estimation and nonideal channel estimation is proposed. The performance of different receiver schemes is deeply explored.The ultra dense network improves the network throughput by reducing the path loss between the base station and terminal users, increases effectively accept signal also magnifies the interfering signal at the same time. And the rapid increase of density of cells results in strong and complicated interferences. The more advanced noise reduction technology and more effective interference coordination mechanism between cells should be considered and adopted. On the basis of existing LTE ICIC and eICIC technology, the thesis has proposed an algorithm of dynamic eICIC on 5G ultra dense network. The algorithm dynamicly adjusts the eICIC configuration according to ultra dense network under different business load, and considers mobility of users and cells in order to improve network performance.