Objective The mainstream signaling systems for suburban railways are CTCS2+ATO （Chinese train control system level 2 + automatic train operation） and CBTC （communication-based train control）. The selection of an appropriate signaling system should be based on the specific characteristics of the suburban railway line and the operational requirements for public transit and networked services.

Method The fundamental functions required of signaling systems to meet the needs of public transit and networked operations in suburban railways are analyzed. The key technical indicators of the CTCS2+ATO and CBTC systems are compared, along with their respective adaptability to public transit and networked operations. The basic principles for selecting signaling system types for suburban railways are summarized.

Result & Conclusion  The choice of signaling system type should align with the primary role of the suburban railway line within the overall network. The CTCS2+ATO system is more suitable for networked operations and for backbone lines within the network, whereas the CBTC system is better suited to public transit operations and to branch lines or independently operated lines within the network.