TD-LTE网络CSFB时延优化研究

Time-delayoptimization research Of CSFB in TD-LTE network

TD-LTE建网初期,话音业务目前使用CSFB方式,存在的主要问题为时延较长。优化前石家庄TD-LTE网络CSFB时延为11.08 s,通过详细分析CSFB信令流程,找出非重要信令开关、TCH立即指配、UE不活动定时器、被叫选择性鉴权等4类可优化参数,分别进行对比验证,时延缩短效果明显,并通过总结优化成果,综合调整网络参数。通过优化调整,石家庄CSFB时延已缩短至10 s以内,优化效果显著,有效提升网络运行质量与客户感知。

During the early state of TD-LTE network, the voice service is using CSFB method, which has the main defect of long time delay. In 2014 the time-delay of Shijiazhuang TD-LTE network is 11.08 seconds, through a detailed analysis of CSFB signaling processto fi nd out the followingfour categoriesparameters whichcan be optimized ,such as non-critical signaling switches, TCH immediate assignment, UE inactivity timer, called selective authentication .wecompared and found out the shorten of the CSFB delay effect is obvious, by summarizing the results of optimization, comprehensive adjustment of network parameters.The time delay of Shijiazhuang TD-LTE network has been reduced to 10 seconds in 2015. The optimizing effect is signifi cant and effectively improve the network operating quality and customer perception.