Research Of Power Control Technique For MBMS Based On WCDMA System

With the rapid development of mobile communication technology in recent years, on the mobile terminal to achieve a more rich data services such as multimedia messages, video on demand, music downloads and mobile TV and so on, have become increasingly hot. A large number of Usage challenges the traditional manner of radio bearer with point to point. 3GPP Release 6 introduces the Multimedia Broadcast Multicast Service, in order to achieve point to multipoint services and share network resources especially air interface resource.This paper firstly elaborates the basic profiles of the MBMS services. Know about the background on which the MBMS service is proposed and currently developing issues. Explore the changes of network structure arising from the MBMS service, including the function entities. Track the processes and radio bearer of achieving MBMS.Then make a more detailed description to the WCDMA system which is related to this paper's research. Learn about the basic structure of radio access network about WCDMA and functions of network elements. Learn about code resource management strategies of the WCDMA system. Talk about problem about the downlink capacity of the WCDMA system including the factors that affect capacity and technologies of improving it.And then study the power control technologies on the WCDMA system. Know about the importance of power control technologies to enhance the performance of the WCDMA system. Study power control strategies of different types of channels. Focuse on FACH and DCH from 3GPP R6 MBMS, including power control methods and power calculations of them.Finally, focuse on the power control algorithms of MBMS based on the WCDMA system. Summarize the radio bearer algorithms currently proposed on MBMS, including PTP/PTM switching algorithm, FACH dynamic power allocation algorithm, FACH/DCH co-allocation algorithm. Simulate to these algorithms, analyse their performances, and then put forward an improved FACH/DCH dynamic co-allocation algorithm.