1. Rail transit signal properties: used for train route control, train interval control, dispatching command, information management, equipment status monitoring and maintenance management. Characteristics of railway signal: the general name of technical equipment on the railway to ensure the safety of operation and shunting, improve the passing capacity of stations and sections, the ability of train disintegration and improve the working conditions of operators.

2. Signal function of rail transit: Through ATS station equipment, basic information such as track occupation status, route status, train operation status, signal equipment failure and so on provided by wayside and on-board ATP can be collected to control and supervise train operation. Railway signal function: Because of the huge inertia of high-speed trains, they can't stop immediately when they are in danger, and it takes a long "braking distance" from braking to full stop, which will cause head-on collision or rear-end collision. Therefore, signal equipment must be used to ensure that trains run at certain intervals in the section to ensure the safety of section operation and improve transportation efficiency.