Research And Implementation Of VoLTE Technology Based On Tianjin Unicom LTE Network

With the rapid development of smart phone and kinds of application softwares in recent years,the bandwidth and wireless internet speed of traditional 2G/3G network can not meet the demand of surfing online.LTE has become the urgent choice for developing mobile network all around the world.More than 200 operators has put LTE network into commercial use and the number of LTE subscribers is increasing rapidly.In China,LTE subscribers of Chinaunicom has reached 175 million,and more and more 2G/3G subscribers become LTE subscribers.Voice service is not only one of the main demand of mobile phone uses but also the main revenue resource of operators.As there is no circuit switch domain in LTE network,which carries voice services in 2G/3G network.It has become a topic needs to be discussed and further studied that how to offer high speed data service as well as high-quality voice service.First of all,this paper briefly analysizes three voice solutions of LTE network.VoLTE technology based on packet switch domain is the final voice solution of LTE network in the future from user experiences,operating costs,maturity of industry chain and other aspects.The paper gives the basic principle,primary business process and the key technical solutions of VoLTE.Based on the principle of volte technology and the current situation of network in Tianjin China Unicom,this paper proposes the method of network element upgrade to deploy VoLTE voice service.The VoLTE service experimental environment has been built based on commercial LTE core network and FDD LTE radio access network.VoLTE service based on LTE network has been successfully realized.The results of VoLTE service tests reach the high definition voice standard in three different environments(the laboratory single base station environment,the commercial LTE network single station environment and the commercial LTE network).