The Design Of Simulation Platform And The Research On Scheduling Algorithm For LTE System

In order to maintain the dominant position in the mobile communications industry, 3GPP initiated the Long Term Evolution(LTE) plan. LTE system which is based on Orthogonal Frequency Division Multiplexing(OFDM) and Multiple Input Multiple Output(MIMO) technology improves the original 3G air access technology. LTE system has the characteristics of high data rate, small delay and full packet based. The research on LTE system has become the core of mobile communications industry. Packet scheduling is an important part of LTE system and its main roles are to prioritize users and allocate radio resources flexibly for users in the limited spectral bandwidths according to a particular mechanism to improve the utilization rate of radio resources. Therefore, the research on scheduling algorithms is the precondition of improving the system throughput and guaranteeing the fairness among users. The main contents of this paper are as follows:Firstly, the LTE system protocol specifications are analyzed. The standardization process, the principles and the key technologies of LTE system are introduced in detail.Secondly, the related concepts about system-level simulation are illustrated. Then, LTE system framework is presented and each module of the system is modeled according to the related protocol specifications. Thus, the LTE system-level simulation platform is set up. In addition, the further optimization of the simulation platform is implemented.Thirdly, the concept of packet scheduling is outlined and three kinds of typical scheduling algorithms are introduced in detail. Then, three scheduling algorithms are simulated in the designed platform in this paper. Furthermore, the simulation results of three algorithms are compared with their theoretical analysis to verify the validity of the platform.Finally, the typical proportional fair(PF) scheduling algorithm is improved to enhance system performance. Then, the improved scheduling algorithm is simulated in the designed platform to validate its superiority of enhancing system performance over the original PF algorithm.