Research On Radio Resource Management Techniques In LTE Systems

With the development of mobile internet and the wide spread of intelligent terminals, data service has shown explosive growth in the past few years. The mobile users’requirement is no longer limited to the low data rate voice service, but shows more interest in the service with much higher data rate. As a result,3G can no longer independently cope with the pressure brought by the growing mobile data services. LTE, which was introduced by3GPP, is promising to alleviate the situation. However, operators have to face the challenges such as the scarcity of spectrum resources, high cost due to large-scale deployment of networks, and high energy consumptions. In this context, it is significantly important to improve the utilization of networks resources through researching on the ways to improve the spectral efficiency, achieving the physical resource sharing among multiple networks, and making full use of other networks, especially WLAN, to offload for LTE networks.The following aspects are covered in this paper.Based on EDF and PF algorithms, an efficient resource scheduling algorithm which aims at enhancing the QoS of LTE systems and improving the spectral efficiency is proposed and extensive simulations are conducted to evaluate the algorithm. The proposed algorithm is able to improve the QoS of mobile users in terms throughput, packet loss rate, packet delay, and fairness. In the meantime, the algorithm has a relatively low computational complexity, which is beneficial to improve the scheduling efficiency, especially in the case of high load.Virtualization technology is introduced to the mobile networks for physical resource sharing among multiple different networks. Virtualization model for LTE networks is proposed, and investigations and analysis on wireless resource sharing among LTE virtual networks are presented. Simulation results demonstrate that resource utilization can be effectively improved through resource sharing, which is meaningful for the application of virtualization in the cellular network.Two types of resource sharing strategies (i.e., proportional allocation strategy and bankruptcy gaming allocation strategy) are proposed respectively so as to effectively achieve resource sharing among virtual networks. Theoretical analysis and simulations on wireless spectrum resource allocation and sharing among different LTE virtual networks indicate that the proposed sharing strategies are applicable and the bankruptcy gaming allocation strategy highlights with greater allocation flexibility compared with the proportional allocation strategy.WLAN network is able to offload for LTE network with overlapped deployment. A novel network selection approach based on the combination of analytic hierarchy process and game theory is proposed, taking the users’ preferences and networks’situations into account. Simulation results demonstrate that the proposed approach can effectively control the frequency of vertical handover, avoiding the ping-pong effect caused by frequent handovers. In addition, the proposed method has a significant effect in reducing the wrong choice of optimal targeted network, which contributes to making full use of network resources.