Technology Of Dual Connectivity In Lte-Advanced System

During the last few years, the rapid development of mobile Internet and smart phones has promoted explosive growth in diverse data applications over cellular networks. It is forecasted that the network capacity requirement will increase thousands of times within the next ten years. To satisfy future service requirement, the existing mobile broadband networks need to be enhanced. LTE networks have been commercialized in several fields to provide mobile broadband services. While it is increasingly difficult and expensive for macro networks to provide effective and flexible capacity expansion through cell splitting, the current deployment of low-power nodes called small cells is more attractive. Therefore the focus of this thesis is the small cell enhancement technology of dual connectivity.Firstly, this thesis introduces the techonology of dual connectivity which is one of the newly proposed small cell enhancement techonologies in Release12. Then based on this background, this thesis analyzes the target scenarios as well as requirements of dual connectivity. The architectures as well as protocols of control plane and user plane of dual connectivity are also represented in this thesis.Secondly, this thesis analyzes the potential problems in the techonology of dual connectivity due to the existence of non-ideal backhaul. Then, based on these problems, we enhance the imperfect aspects of the traditional power control mechanism in LTE system and propose three semi-static power splitting schemes. Simulation results show that the schemes we propose can decrease the probability of power scaling as well as increase uplink system throughput. Furthermore, according to3GPP RAN2agreements, there are some problems related to buffer status report (BSR) in the architecture of3C in dual connectivity. Thus, in this thesis, some schemes are proposed to resolve these problems on BSR. Simulation results show that these proposed schemes can improve the data rate of an UE.