The Research Of Interference Coordination In Heterogeneous Network

With the continuous development of mobile communication technology, the requirements of future wireless communications will be higher in coverage and capacity of network, the application and research of key technology for Heterogeneous Network have become more and more urgent. However, the interference problems of Heterogeneous Network are becoming a major problem which hinders the development of the communication network. In order to solve the interference problems mentioned above, the interference coordination technology of Heterogeneous Network needs to be further researched urgently. At the same time, frequency resource scheduling and power control as two key aspects of interference coordination technology need more and more attention, the two key aspects are also the resource and research emphasis of this paper.Firstly this paper shows us the background and significance of the research, it also briefly introduces the related research results during my period of master, and shows the overall structure of the paper. Then it analyzes and summarizes the key technologies of LTE and LTE-Advanced system, focuses on the interference coordination technology of Heterogeneous Network, and thus leads to the main research contents of this paper.First, in view of the existing spectrum resource allocation and scheduling algorithm in Heterogeneous Network is too simple, this paper puts forward a kind of frequency resource allocation algorithm based on graph theory. By establishing the mathematical model, structuring user interference graph, categorizing users, and assigning different channels to each kind of users, this algorithm reduces the interference between users and improves the system throughput. Simulation results show that the algorithm can reduce the number of high interference users and improve system throughput effectively. Secondly, in view of the existing power control algorithm cannot take the interference of macro users and Pico users into consideration at the same time, this paper presents an improved power control algorithm which can guarantee the low interference of Pico-users and minimize the interference of macro users. The simulation results show that the effect of the improved algorithm in reducing interference between users and enhancing the overall throughput of the system is obvious.