Research On Scheduling Algorithms Of HSDPA In TD-SCDMA System

In order to meet the increasing demand for high data rate in mobile scenario,the 3rd Generation Partnership Project(3GPP)has introduced a new technique which is referred to High Speed Downlink Packet Acccess(HSDPA).As an evolution technique of TD-SCDMA,HSDPA can increase the peak downlink data rate to 2.8Mbps from384 kbps,by employing some new features such as fast scheduling,HARQ and MCS.HSDPA can also shorten the transmission delay.Among all these new features,the fast scheduling algorithm is a key component which can significantly impact the performance of the whole 3G system.In this paper we start from concept and principles of HSDPA,all key features of HSDPA are studied one by one.We develop a system-level simulation platform using OPNET,which can fanciliate the performance study of Radio Resource Management(RRM)algorithm in HSDPA system,especially scheduling algorithm.In this paper we propose a new scheduling algorithm for multi-services scenario.In its calculation of user priority in scheduling,we provide weighing factors for delay and Guranteed Bit Rate(GBR)of different services,so that Qo S of each services can be fulfilled,at the same time total throughput of the whole system is maximized.A comparison between the proposed algorithm and existing scheduling algorithms has been done using the aforementioned simulation platform.