Research On Resource Scheduling Algorithms In TD-LTE-Advanced System

With more and more Internet severice based on the mobile terminal andmultiple severice request, people demand higher data speed in wirelesscommunication systems and pursue the convenience of access the network bymobile terminal. In2004,3GPP initiated the process of LTE which will be as3.9Gcommunication technology. Meanwhile, China also proposed TD-LTE to3GPPwhich is a mobile communication systems as the evolution of TD-SCDMA version,and on the basis of TD-LTE, China completed the4G communication technologyTD-LTE-Advanced,which meet technology standard proposed by IMT-Advanced.TD-LTE-Advanced technologies require higher peak rates, smaller time delay, thegreater spectrum efficiency. And these goals are difficult to achieve only alone byphysical layer technology development, efficient management and resourceallocation applied in TD-LTE-Advanced system which can play a positive role toadvance the wireless system performance is becoming increasingly prominent.Resource allocation optimization in TD-LTE-Advanced system will become theimportant means to enhance the system performance in the next generation wirelessnetworks.This paper mainly analyses the resrouce allocation algorithms and proposed anew resource allocation algorithm called TD-FD-PF algorithm which combinesTime Domain and Frequecy Domain allocation based on Proportional Fair. Firstlythis paper introduces the background and the significance of the research. Then abrief introduction about TD-LTE-Advanced system is given, focus on the linkadaptive technology and some key technology which support the performance ofTD-LTE-Advanced system. Secondly this paper gives a detailed analysis ofresource scheduling process in TD-LTE-Advanced and compares some currentresource allocation algorithms. Lastly this paper proposed a new resource allocationalgorithm called TD-FD-PF, which can be applied in TD-LTE-Advancedsystem.Since TD-LTE-Advanced system uses SC-FDMA technology as uplinkmultiple access technology, while the downlink uses OFDMA technology, this paperrespectively simulates the proposed TD-FD-PF algorithm on uplink and downlink.Simulation results show that the proposed algorithm has a higher systemthroughput than the classic Proportional Fair algorithm, and the Jain fairness index,which is to measure the fairness among users, approaches one, this indicates thefairness of the proposed algorithm is superior than the classical Proportional Fairalgorithm, and accordance to3GPP fairness C.D.F curve, the algorithm this paper proposed is complete to meet the fairness of the curve, and equally superior than theclassical Proportional Fair algorithm. And with the increase in the number of usersin the system, the proposed algorithm performance gain is more evident than theclassic Proportional Fair algorithm.