Abstract: Based on the principle of CIR function number registration, through viewing CIR data, accessing wireless network management information, and on-site wireless network environment testing, etc., this paper analyzes the causes of 5 function number registration failure cases encountered in routine maintenance, and gives the solution to prevent users such as stations and dispatchers from being unable to communicate with the train driver in time due to the failure of function number registration, so as to ensure the normal GSM-R voice service.

Key words: CIR, function number, cause analysis

摘要： 以机车综合无线通信设备（CIR）功能号注册原理为基础，通过查看CIR数据、调阅无线网管信息以及现场无线网络环境测试等方式，对日常维护中所遇到的5个功能号注册失败案例进行原因分析，并给出解决方案，以防范功能号注册失败导致车站、调度员等用户无法及时与列车司机进行通信联系，保证GSM-R话音业务正常。

关键词: CIR, 功能号, 原因分析