Research On Multimedia Broadcast Multicast Technology Based On Opnet

With the rapidly development of mobile communications and the increasing demands for multimedia,3GPP introduced Multimedia Broadcast Multicast Service(MBMS)in R6 so as to transmitting multimedia services efficiently.3GPP defined e MBMS in R8 in order to meet people's various demands for multimedia applications.Broadcast Multicast Single Frequency Network(MBSFN)transmission mode is introduced by e MBMS.The MBSFN is an effective solution to some problems,such as the irrational use of wireless resources,the instable reception and blind cover and so on.This thesis have studied the following researches about the e MBMS related technology,.First of all,the evolving process of e MBMS and related technical the ories are elaborated.The e MBMS protocol,e MBMS transmission mode,and multiple antenna(MIMO)technology are highlighted.Secondly,the method of combining theory with simulation is used to analyze the two transmission methods of e MBMS.The influence of cell radius on MBSFN area coverage performance is studied.And it concludes that the smaller the cell coverage radius is,the better the MBSFN coverage performance is.The influence of MIMO technology on MBSFN transmission performance is studied.The performances are compared when using open-loop space diversity and open-loop spatial multiplexing in e MBMS application scenarios.Finally,in order to further improve the performance of MBSFN transmission,a group-based multicast transmission scheme is proposed by studying the transmission characteristics of MBSFN area.At the same time,the inter-carrier interference(ICI)caused by the Doppler shift will affect the performance of the group users when the users move at high speeds.By establishing the signal and channel model,the ICI will be modeled as Gaussian noise,and then analyze the performance of the proposed scheme by simulations.