Voice communications

At the Zurich dispatching center, dispatchers have the option of talking with operators in stations and with train drivers either on a telephone, or with a speaker phone so that nearby people in the Zurich center can hear the conversation and be informed immediately.

One shortcoming of the current voice system, which SBB hopes to remedy in the future, is that the dispatcher can talk to either one train or all trains in a district, but not two or more selected trains.

In a future system, both the driver and the passenger attendant in a train will use their mobile phones to check in with the dispatching center. The dispatching center will then be able to reach one or both of them during a trip, and will be even able to make public-address announcements in the train via the crew's mobile phones.

These mobile phones will be based on the GSM standard, and thus eliminate the need for SBB to have its own internal communications network. Despite being a public network, the GSM technology is considered secure enough to transmit safety-related information (both voice and data).

At the Altstetten control center, the same Information Management System (IMS) for voice communication that is installed in the Zurich dispatching center allows the operator to speak:

• to passengers over the loudspeaker systems in the stations,

• with train drivers and other employees in permanently-mounted speaker phones located out among the terminal tracks,

• over telephone links with neighboring stations, and

• over radio links with local people such as switching locomotives that need a path or construction crews that need the closure of track sections.