GSM-R基站子系统同步方案研究

Research on Clock Synchronization Scheme of GSM-R Base Station Subsystem

介绍了目前GSM-R系统同步组网结构,总结了该组网结构与国内外行业标准的差别;对比分析了再定时、外部时钟输入和空口软同步3种时钟同步改进方案的优缺点;在实验室搭建测试环境,分2种场景对再定时功能进行了测试,得出再定时功能更适用于具有良好精度和稳定度的时钟参考源的传输设备;以郑西高铁故障为例.验证了再定时功能的作用和不足;根据工程投资和设备接口等情况,提出了4种同步组网建议方案,供工程设计和设备招标参考。

The synchronization networking structure of the current GSM-R system is introduced and the differences between the structure and the industry standards from home and abroad are summarized.Then,the advantages and disadvantages of three clock synchronization improvement schemes:retiming,external clock synchronization,and air interface soft synchronization,are compared and analyzed.In addition we set up a test environment in the laboratory and made a test on the function of retiming in two scenarios.The test results show that the retiming function is more suitable for transmission equipment with clock reference sources of good precision and stability.Furthermore*we tested the function of retiming in Zhengzhou-Xian high-speed railway to validate its role and defects.According to the situation of project investment and equipment interface,we put forward four proposals for synchronous networking,offering reference for project design and equipment bidding.