A signal system undertakes the task of real-time control and status monitoring on a variety of train operation equipment and operating trains. With the increase of running speed and densification of tracking interval of trains，traffic safety cannot be guaranteed by completely relying on manual observation and driving. Therefore，the train operation control system must be installed to realize the automatic control of intervals and speed of trains，improve transport efficiency and ensure traffic safety. By making use of communication technology，communication-based train operation control system （CBTC） contributes to the realization of speed control through information exchange of vehicle equipment and on-site communication equipment with the station or train control center so as to ensure traffic safety，protect and assist passengers，assist train operation and driving and provide technical support. China’s independent CBTC research team finally completed the development of engineering prototype at the end of 2008 after 10 years of unremitting efforts. At the end of 2009，the Yizhuang Line-the demonstration project of CBTC train operation control system with independent intellectual property rights，for which the Beijing Traffic Control Technology Co.，Ltd. is responsible-was put into operation. Compared with the traditional CBTC system，the vehicle-to-vehicle communication signal system has the advantages of high performance，high reliability，low cost，easy construction and maintenance，modularization and interconnection support and will become the future development direction of the CBTC system.