Evaluation And Optimization Of WCDMA And LTE Network Interoperability

With the rapid development of the domestic 4G construction, in order to bring opportunities for the major operators to seize the market at the same time, it also brings greater technical challenges. In order to make better customer service experience, the core issue of competition between operators is improving network quality. However, early in the 4G network networking, communication system can not implement continuous complete coverage, in order to ensure the smooth transition and evolution of network, Wideband Code Division Multiple Acces (WCDMA) and Long Term Evolution (LTE) network integration of networking will be the main form of the network for a period of time in the future, and WCDMA and LTE network interoperability is the key technology, will directly affect the entire network of network quality and customer service experience. The purpose of this paper is to study the interoperability technology of WCDMA and LTE networks, establish an evaluation system, which is used for performance evaluation analysis and enhance system capacity, and optimize the customer service experience.Combining the characteristics of China Unicorn's network, This thesis summarizes and compares the scenarios of WCDMA and LTE network interoperability, selects representative Voice over LTE (VoLTE) scenarios,and combs the signaling flow of the attached registration, call and handover process.This thesis evaluates and analyzes the VoLTE voice performance,establishing of VoLTE performance evaluation system, combined with China Unicom VoLTE business, VoLTE signaling process and expert advice, selecting the VoLTE performance indicators; then, according to the test data of the laboratory and the existing network, combined with the VoLTE performance indicators, evaluate and analyse VoLTE performance.After that, combined with the example of capturing packets on the existing network, the typical problems of VoLTE voice are analyzed.This thesis is researched for optimizing VoLTE, combined the typical scenarios of voice services in the existing network, analyzing the wireless network optimization method. To summarize 10 typical scenes, the whole idea is put forward and optimized according to the different scenarios.Then with VoLTE voice and data traffic concurrency scenarios, based on resource allocation scheduling problem, this paper proposes an improved scheme of semi-persistent scheduling algorithm in VoLTE voice and data service concurrent scenario. This scheme combines the time-varying channel quality and the VoLTE voice code rate, it allocates the resources of the voice and data service users reasonably. The simulation results show that the improved scheme can effectively reduce the Block Error Rate(BLER) of VoLTE users, guarantee the resource allocation of data service of users, and improve the throughput of data services, reduce the impact of voice services on data services at the same time. It can save network resources and improve the system capacity.