Dual Network Design Of Metro Broadcasting System

The problems brought by large capacity traffic often restrict the development of cities.In order to deal with the problem of traffic congestion,subway has been rapidly promoted and applied in major cities.Subway as a public transport,its speed and efficiency is incomparable to other means of transport,but at the same time,its safety and ride comfort is also one of the criteria to measure its quality.With the advent of subway broadcasting system,although its importance is not as important as power system and braking system,but in some cases,the stable operation of the broadcasting system also indirectly affects the safe operation of the whole subway system,more directly affects the comfort of passengers.For the design of audio broadcast bus,there are about two stages.The first stage is analog broadcast.At the beginning of subway,the design of digital circuit has not been formed yet.During this period,analog broadcast is mainly used.With the development of IC circuit and Ethernet,the voice broadcast network based on digital Ethernet has been widely used in the 21 st century.However,due to the excessive dependence of digital broadcasting on the digital network,the stability of the digital network cannot be guaranteed,so the pure digital network voice broadcasting system has a high failure rate.In view of this situation,this paper proposes the design and implementation of a digital and analog dual redundancy Metro voice broadcasting network,which can realize both digital and analog broadcasting networks on a metro broadcasting system.When working,digital network is preferred as the main channel of voice broadcasting.The working state of the broadcasting system network is monitored in real time.When the digital network fails,it will switch to the analog network in the first time,and the digital network will carry out self-repair work.After the repair of the digital network,choose to switch back to the digital network or continue to work with the analog network until the power is off.This paper presents the design and implementation of key broadcast subsystem,including artificial voice broadcast system,prerecorded audio broadcast system,radio broadcast system,driver intercom system and passenger emergency intercom system.Aiming at the key equipment,cab broadcast control box,this paper presents the detailed circuit design,which realizes the digital network and analog network system respectively.On this basis,the design and implementation of dual network redundancy are proposed.Finally,according to the dual network redundancy design proposed in this paper,the field test is carried out on the real vehicle.The results show that the dual channel redundancy design of the subway voice broadcast system proposed in this paper can greatly reduce the failure rate of the broadcast network and improve the safety and stability of the subway operation.