The Engineering Design Of Public Mobile Communication Leading-in System On Metro

With the development of economic and technology, urban rail transit developed very fast in recent years, most of people will select metro as their traffic tool because the subway is one of the most efficient, convenient and safe traffic tool. however, people have higher and higher requirement to mobile communication.They are not only satisfied with high quality service outdoor, but also like to enjoy excellent service underground, for example, metro,underground parking and supermarket, while the mobile signal will be very weak due to subway's special structure and cell phone is unavailable in such area. How to solve the signal coverage underground, satisfy demends of customers and avoid building redundant project for the various operators'different distribution system, it is most important consideration issue for the Metro Management Company.The most effective method to solve underground signal coverage issue described above is to install one set of public mobile communication leading-in system. The system will employ POI, and the various BTS will be installed in the every station, the signal coverage will be implemented through the leaky coaxial cable in tunnel and antenna of the platform and station hall. The optimum proposals with passive and active have been offered after integrated consideration. Next we have made more detail link calculation based on the coverage proposal to ensure to meet the demand of the coverage restricted condition. At the same time, we have made the analysis and calculation for the signal handover according to the coverage proposal and link calculation, it can satisfy switchover condition. At last we also have an overall analysis and plan for the integrated supervision system in order to work smoothly for the Public Mobile Communicaton Leading-in System.This system can implement the compose function of multi-signal, and avoid the repetitious investments of wireless distributing system, it is effect means to implement multi-network signal compatible overcast. The paper can provide reference and successful experiences for the other metro company, so it has some economic and social meaning.