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Traffic information radio, which was first introduced in Europe in 1974, is no longer able to satisfy the demands for an effective information system designed to report on current traffic conditions. In attempts to improve this situation, there are currently several different approaches being pursued. The BEVEI II project proofs that it is possible to construct an efficient digital traffic information system using the RDS data channel on FM radio. One alternative is a system as currently used in Great Britain. This system represents the actual traffic situation on all main national roads, including an update of approximately every 3 minutes. Another traffic information system is in the planning in Germany using the GSM mobile telephone network. This system is the basis for many other telematics services. Examples of terminal equipment required for this purpose in the vehicle will be presented.

A new type of FM receiving system is introduced which eliminates most of the well known typical distortions due to the properties of the mobile radio channel. The system consists of several antenna elements mounted on a car and a special receiver which combines their individual RF signals in order to minimize distortion. In contrast to conventional antenna diversity systems, the new system does not switch between the available antenna elements, instead the signals are modified in amplitude and phase, and then added to each other. The resulting shape of the receiving pattern of the antenna system is directed in such a way that the S/N ratio is maximized and the effect of interference minimized.