Abstract: A radio broadcasting system, transmitter, receiver, method and signal are provided wherein a program signal is combined with a data signal, the data signal not only includes information on an indicated program signal, but also data of a data service and information on the data service, such as, an identification of the data service, alternative frequencies, information on related data services etc. In this way, it is possible to broadcast the data service on a network differing from the network broadcasting the program signal. This is of particular use in the Radio Data System.

Abstract: A radio broadcasting system, a transmitter and a receiver for use in such a system, a radio broadcasting method and a radio broadcasting signal.

Abstract: A radio broadcasting system, transmitter, receiver, method and signal are provided wherein a program signal is combined with a data signal. According to the invention the data signal not only includes information on an indicated program signal, but also data of a data service and information on the data service, such as an identification of the data service, alternative frequencies, information on related data services etc. In this way it is possible to broadcast the data service on a network differing from the network broadcasting the program signal. This is of particular use in the Radio Data System.

Abstract: A system for transferring data in group, wherein groups have group identifiers for distinguishing groups comprising different data types. A group can be reassigned to carry a different type of data by transmitting in special groups having a predetermined group identifier, group identifiers and data type identifiers for linking respective group identifiers to respective data types. By transmitting a new data type identifier for certain group identifier that particular group is re-assigned to carry a new data type. This allows the use of a group for a plurality of data types, which is especially useful in the Radio Data System.

Abstract: A method and a system for providing synchronization in a stream of messages. In such a method and system, the stream of messages is arranged in fictitious sequences of messages, in which messages of a predetermined type may only occupy a certain number of locations within a sequence. In this way, the messages of the predetermined type are concentrated in a part of the sequence, which allows a receiver to use the time during which the remaining part of the sequence is transmitted for other purposes, such as scanning of the reception band, etc.

Abstract: In a system for transmitting data, having a transmitting station and at least one receiving station, data is transmitted in packets of a first type, including a first data type identifier and data, and a second data type identifier, indicative of the type or nature of the data, is transmitted in a packet of a second type, including a further first data type identifier and the second data type identifier, wherein the first data type identifier and further first data type identifier are provided for linking the second data type identifier to the data. As the length of the first data type identifier is shorter than the length of the second data type identifier, the efficiency of the packets of the first type is improved in comparison with a system which only transmits packets of a first type, including the second data type identifier and the data. The invention is especially useful in RDS, wherein the packet of the first type is a version A group and a packet of the second type is a version B group.

Abstract: FM-receiver comprising an aerial input having connected thereto, in succession, an RF input stage, an IF portion, an FM-detector and a stereo decoder having a mono-stereo control circuit therein, also a control signal generating circuit being connected thereto, the control signal generating circuit comprising a multipath reception detector and being connected to the IF portion via a level detector, the multipath reception detector comprising an amplitude detector connected to the level detector via a bandpass filter. The FM-receiver also comprises a noise pulse suppression circuit arranged between the FM-detector and the stereo decoder for keeping the amplitude of the stereo multiplex signal constant during the occurrence of noise pulses.

Abstract: Receiver comprising a field-strength detector for measuring the received signal amplitude and a noise reduction circuit connected thereto via a control signal generating device for reducing audio-frequency noise in the output signal of the receiver, which control signal generating device has an attack and a recovery time constant at a decrease and an increase, respectively, of the received signal amplitude measured by the field strength detector, the recovery time constant being greater than the attack time constant. By adequate control of the cross-talk attenuation of a stereo signal and of the audio band-width, sudden variations in the sound quality at rapid and large field strength variations are prevented. To this end the control must be continuous and must, in the event of field strength variations follow the decrease of the field strength more rapidly than the increase.