Despite reluctance to develop screen-based functionality that might bring RDS into competition with television, the utility of being able to print out information such as weather maps or even advertising was regarded as potentially interesting to both radio and television manufacturers alike. This prototype, unveiled in 1989, incorporated a liquid-crystal display capable of showing images such as weather maps, accompanied by "a light pen with which the radio can be programmed from barcodes", these barcodes encoding programme information, and supported detachable modules, of which a cassette player module and a printer module were developed. Having received no manufacturer interest, however, the corporation engaged designers at Kinneir Dufort to produce a prototype showcasing these features. Of the three broadcasting partners of the EBU, the BBC were reportedly pursuing the application of RDS technology most enthusiastically and sought to attract bids from manufacturers to make a "BBC-accredited radio" supporting RDS features. The EBU issued the first RDS specification in 1984. The modulation system was based on that used in a Swedish paging system and the baseband coding was a new design, mainly developed by the British Broadcasting Corporation (BBC) and the IRT. The EBU Technical Committee launched a project at its 1974 Paris meeting to develop a technology with similar purposes to ARI, but which was more flexible and which would enable automated retuning of a receiver where a broadcast network transmitted the same radio programme on a number of different frequencies. ARI used a 57-kHz subcarrier to indicate the presence of traffic information in an FM radio broadcast. RDS was inspired by the development of the Autofahrer-Rundfunk-Informationssystem (ARI) in Germany by the Institut für Rundfunktechnik (IRT) and the radio manufacturer Blaupunkt. RDS defines many features including how private (in-house) or other undefined features can be "packaged" in unused program groups. The data is sent with an error correction code, but receivers may choose to use it only for error detection without correction. (The stereo difference signal extends up 38 kHz + 15 kHz = 53 kHz, leaving 4 kHz for the lower sideband of the RDS signal.) The RBDS/RDS subcarrier was set to the third harmonic of the 19 kHz FM stereo pilot tone to minimize interference and intermodulation between the data signal, the stereo pilot and the 38 kHz DSB-SC stereo difference signal. The two standards are only slightly different, with receivers able to work with either system with only minor inconsistencies in the displayed data.īoth versions carry data at 1,187.5 bits per second on a 57 kHz subcarrier, so there are exactly 48 cycles of subcarrier during every data bit. Radio Broadcast Data System ( RBDS) is the official name used for the U.S. The standard began as a project of the European Broadcasting Union (EBU), but has since become an international standard of the International Electrotechnical Commission (IEC). RDS standardizes several types of information transmitted, including time, station identification and program information. Radio Data System ( RDS) is a communications protocol standard for embedding small amounts of digital information in conventional FM radio broadcasts. Communications protocol standard in FM radio broadcasts
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