Load Balancing Technology For Heterogeneous Wireless Networks

Today, with the widespread popularity of a variety of intelligent terminals and the wide range of multimedia applications, broadband wireless network traffic grows exponentially. Therefore, the mobile network needs to provide higher coverage quality and greater data rate to ensure the user experience.In order to solve the above problem, the heterogeneous network technology is proposed by 3GPP in the course of LTE-A standard formulation.Compared with the traditional networking, the interference environment in the heterogeneous network is more complex, and it is very important to solve the inter-cell interference problem.At the same time, as one of the important functions of the self-organizing network, the load balancing technology can improve the network coverage performance and optimize the system capacity. Therefore, it is the focus of this thesis to realize load balance of heterogeneous wireless networks based on reducing inter-cell interference.In this thesis the load balancing algorithm and its optimization is studied under Macro-Pico heterogeneous networking. Firstly, this thesis analyzes and summarizes the current situation of the load balancing algorithm and the inter-cell interference coordination algorithm both at home and abroad.Then, the system architecture and key technologies of LTE-A are briefly introduced, and the principles and classification of load balancing technology and inter-cell interference coordination technology are expounded in detail. Based on this, an optimized load balancing scheme based on enhanced inter-cell interference coordination technology is proposed, which includes the Macro-Pico optimized load balancing algorithm based on almost blank sub-frame technology and the Macro-Macro optimized load balancing algorithm based on semi-static soft frequency reuse.Finally, this thesis builds LTE-A system level heterogeneous wireless network simulation platform, and compares and analyzes throughput and the number of light and heavy load area ratio of the optimized load balancing scheme proposed in this thesis with the existing load balancing scheme. Simulation results show that the proposed optimization scheme not only achieves better load balancing among the cells, but also improves resource utilization and system throughput.