Research On Optimal User Scheduling And Interference Coordination Mechanism In The LTE System

With vigorous development of all kinds of internet application,3G Networks can not satisfy customers’increasing needs any more. Nowadays the global communication industry displays the traits of Mobility, Broadband and IP-based Architecture. Limited frequency resource becomes the leading factor to the improvement of system performance along with the development of mobile telecommunication, and how to improve the frequency efficiency is one of the pop topic in researching area. Especially with the developments of wideband wireless access technology like WiMAX, HSDPA technology could not satisfy the requirements of more broadband bandwidth and high video streaming service in the future. Most of the operators world wide have chose LTE as their evolution tendency of future networks, LTE has became the winner standard of4G. LTE system is the wireless access technology forwarded by3GPP,which can realize more bandwidth and high bit rate and the key technology for physical downlink is OFDM. So, the inter-cell interference is the top problem to solve.After introducing the background knowledge and development of the next generation wireless network-LTE, the network structure and key technologies of LTE are studied in this paper, and many advantages and characteristics of LTE are put forward. Then, The classification, QoS guideline and the target of the packet scheduling algorithm are introduced. With four classical packet scheduling algorithms available lucubrated, their performances and shortages are analyzed. Finally, the four algorithms are analyzed and simulated.Later the introduction of inter-cell interference suppression technique, the source of interference in LTE system, the harm of interference, and more mainstream interference suppression techniques in present. Then research the inter-cell interference coordinate projects, detailed introduces several frequency reuse technique, especially soft frequency reuse, from a different direction introduced the soft frequency reuse. And among which the soft frequency reuse scheme, which is very popular in current researching area.The soft frequency reuse technique is studied in this paper, a based on traffic load dynamic interference coordination plan was proposed, combine the use of different frequency reuse scheme, realize the interference coordination algorithm of dynamic real-time adjustment in the cell, To solve the problem of low Spectrum utilization rate and the low system throughput low in the static interference coordination, at the same time, it makes the interference coordination more flexible, in the further development of the LTE system has a broad prospect of application. With some of the earlier interference coordination scheme comparison, the new scheme has the advantages of these aspects. According to the different network traffic load, interfering with the degree of different, dynamic adjustment use frequency reuse scheme; which could satisfy the performance target better forwarded by3GPP LTE, realizing more balanced bit rate, and then validated by link simulation, which also prove that the optimal scheme could improve the system throughput and the transmission rate of cell edge user, improving the frequency efficiency.