Research On Interference Coordination Techniques For Heterogeneous Network In LTE-Advanced System

LTE, the long term evolution of3G system, is the latest standard for the next generation of mobile communication networks.3GPP (3rd Generation Partnership Project) has already completed the standardization of LTE and started the standardization process of LTE-Advanced system in2009. In LTE-Advanced system, the Macro eNB and Home eNB Heterogeneous Network scenario has been widely used, This network can meet broadband multimedia users'demand for high data rate, and provide good user experience at the same time. However, interference problems between cells in heterogeneous network are more complex than those in the single-layer network. The methods to resolve these problems include descending power settings, and time domain adjustment, etc.This dissertation optimizes the existing downlink power setting algorithm based on the research of the heterogeneous network interference coordination, and puts forward several corresponding optimization schemes. These schemes are simulated and analyzed. The main component is as follows:Firstly, the dissertation studies the structure of LTE-Advanced system and the heterogeneous network interference coordination technology, and analyzes the current situation of the research on the existing downlink power setting algorithm and the possible performance gain.Secondly, based on the existing downlink power setting algorithm, the dissertation analyzes the characteristics of these optimization schemes, and proposes a downlink power setting optimization algorithm based on the pathloss from Femto to macro users nearby from the perspective of self-adaption. The simulation result shows that the optimization algorithm can improve the user performance without interfering with the macro users to receive the control channel.Thirdly, according to the proposed adaptive optimization algorithm, the dissertation analyzes the difficulty in measuring pathloss caused by Femto and how pathloss algorithm ignores the signaling from Marco to UE. A downlink power setting optimization algorithm is put forward based on the detected uplink receiving power spectral density transmitted by the near MUE victims from the perspective of engineering. The simulation result shows that the optimization algorithm can improve the user performance significantly compared with the existing algorithm and other proposed algorithms.