Traffic Message Channel (TMC) is a technology for delivering traffic and travel information to drivers. It is typically digitally coded using the FM-RDS system on conventional FM radiobroadcasts. It can also be transmitted on DAB or satellite radio. It allows silent delivery of high quality accurate, timely and relevant information, in the language chosen by the user and without interrupting normal services. Services, both public and commercial, are now operational in many European countries. When data is integrated directly into a navigation system, this gives the driver the option to take alternative routes to avoid traffic incidents.
How it works
Each traffic incident is sent as a TMC message. One message consists of an event code and a location code in addition to time details.
The message is coded according to the Alert C standard. It contains a list of about 2048 events which can be translated by a TMC receiver into the language of the user.
The source of traffic information is typically police, traffic cameras, loops, floating car data and others.
The following countries provide a TMC service:
(See also TMC link to the right)
Overview TMC in Europe
(click on picture)