The RDS-TMC service (Radio Data System - Traffic Message Channel) displays the current traffic information in the map of the navigation device in the vehicle during the journey. Thus, the driver is virtually instantly informed of all serious incidents that have taken place along his/her route, allowing him/her to respond with an immediate decision.
The traffic information from the NTIC is transmitted to the navigation device in the vehicle in a coded form (TMC) via and inaudible data channel (RDS) that is transmitted as a part of the FM broadcast modulation of a given radio station. The information is coded using international protocol Alert-C, which is language-independent. Receiving the transmission of the traffic information should pose no problems even for foreign drivers.
The RDS-TMC service works in most European countries, in some countries, however, the signal covers only a part of their territory. In some of the other European countries, the launch of the system is being prepared.