Research on Scheduling for VoIP in the LTE-Advanced Relaying System

With the development and maturity of LTE , 3GPP evolution to LTE-Advanced ( referred to as LTE-A) , its goal is to become the ITU IMT-Advanced candidate technology . As a key technology in the LTE-A system , radio relay technology to enhance cell throughput , expanding cell coverage , improve system fairness . At the same time , the future mobile communication systems will build an all-IP access network as well as the pure IP core network , VoIP integration with the fixed-line business will be the only carrier of voice services in LTE and LTE-A system . For the VoIP service is supported in the LTE , 3GPP LTE standardization process has discussed extensively , while in the LTE-A system , introduction of relay technology , research in this area is still in its infancy . Therefore , VoIP scheduling schemes proposed for LTE-A relay system to assess the introduction of relay technology for VoIP performance of the system , will be a high level of research and application value . Based on the above background , the paper mainly VoIP service scheduling in LTE-A relay system . Firstly, a brief introduction of the course of development of LTE and LTE-A project , given the research background and the main contribution . Next, the second chapter describes several typical relay technology , as well as the challenges brought about by the introduction of relay . The third chapter two typical traditional LTE system VoIP scheduling algorithm : dynamic scheduling and semi - persistent scheduling , relay system , and system-level simulation of the relay system VoIP performance under different parameter settings assessment , simulation results show that the introduction of relay technology can bring to enhance the capacity of the system VoIP . In the fourth chapter , the papers according to the characteristics of the relay system for backhaul and access links , respectively, proposed optimal transmission scheme for VoIP services . The simulation results show that the the proposed VoIP optimized transmission scheme can effectively reduce the relay user VoIP packet delay , improve VoIP performance in the relay system . In the fifth chapter , the interference caused by the introduction of relay , the thesis proposes a relay system inter-cell interference coordination program , and the VoIP system performance under the program was evaluated . Finally, the paper summarizes the research work and future research directions prospect .