Interference Coordination For LTE-A Relay Cellular System

With the development of mobile Internet, users require higher performance of mobile communication system.After the standardization scheme of LTE finished by3GPP, LTE-A turns up. In order to reach the requirements ofIMT-Advanced system proposed by ITU, the LTE-A system introduces lots of new technologies. One of them isthe relay technology. The relay technology effectively expands the cell coverage, improves the spectrumefficiency, eliminates the blind spot and enhances the edge users’ performance. However, LTE-A adopts OFDMtechnology to ensure the orthogonality among users in the cell. The OFDM can effectively avoid the interiorinterference. The introduction of relay technology breaks up the orthogonality of the system. It brings the interiorcell interference for LTE-A relay cellular systems which already has the exterior interference among cells. Theseinfluences have a strong impact on the service quality of the cell users, especially cell-edge users, and reduce thecell edge throughput.In order to assess the interference coordination scheme of the existing relay cellular system more intuitive andeffective, the thesis establishes the simulation of the LTE-A relay cellular system. At the same time, it introducesthe various modules and processes used in the simulation. The system provides simulation support for subsequentstudy.After evaluating some existing interference coordination methods of the relay cellular system, the paperproposes a modified spectrum partition model. Based on the original spectrum division scheme which divides thewhole spectrum to center and edge spectrum, the new model makes deeper division for the edge spectrum. Itdynamically changes the inner proportion of the edge spectrum according to the changes of each load in the celledge region. It can use spare spectrum as more as possible.This thesis also designs a half-static spectrum scheduling method based on modified spectrum division model.The method reduces the system costs of signaling exchange to the greatest extent, considers the algorithmcomplexity, thinks about the justice of users and tries its best to improve the spectrum efficiency.