Next RDS Forum meeting on 21 & 22 October at Geneva

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The RDS Forum is a non-profit international professional industry association that has the objective to promote and maintain the RDS technology, which was developed by the European Broadcasting Union (EBU) in the early eighties as an open system to enhance FM broadcasting, primarily to enable automated tuning in mobile FM radio receivers equipped with that then new technology.

Nowadays in 2022, over 38 years later, almost all FM radios in Europe and the USA use RDS. ICs have become available that have an FM receiver and an RDS decoder on the same chip and the price for such a chip, if bought in quantities, is now extremely low, say to give the magnitude, only one Euro. The trend of this price is still falling and the quantity of such chips sold on the world market is still much increasing, now more than one billion units per year. In comparison, the size of the world radio market is just a few billon radio receivers sold each year.

FM/RDS radio is increasingly used in portable devices

Many applications are nowadays within mobile phones and portable devices. The more traditional car radios no longer have a separate RDS decoder IC. RDS decoding is now an integral part of dedicated multi-purpose DSP, necessary for the product even without RDS. In these products the RDS function price is then almost zero, as it is done by software only. The performance of an FM/RDS car radio in difficult receiving conditions, like in mountainous regions, where signal reflections and multipath signal propagation are frequent, depends very much on the car radio and antenna design. If very well equipped with multiple tuners and antenna diversity, such an FM car radio is not performing worse than a digital radio receiver such as DAB. The least is to say is that there is little difference then in reception quality and the audio reproduced by the radio.

The DAB argument that it can out-perform FM with better audio has in the meantime totally lost its value. Nevertheless, digital radio is progressing as many broadcasters and the car industry want to use more and more multimedia options, also using increasingly hybrid radio and audio streaming with the Internet connected car becoming a reality. In this context automatic service following between FM radio, digital radio and Internet radio is also an objective to be achieved.

The RDS specification has been enhanced with three additional subcarriers. Their use with existing receivers is backwards compatible, i.e. the basic RDS features continue to be received totally undisturbed by this innovation. In December 2018 Radio France demonstrated in Nantes the implementation of the new RDS2 File Transfer specification RFT. They used the world’s first commercially available RDS2 encoder from WorldCast Systems in Bordeaux and a newly developed RDS2 home receiver prototype from Caméon, made for Radio France. They showed the transmission of music cover art and station logo using file sizes of up to 20 KB. The time needed to receive the files was about twice as long compared with DAB, but still very acceptable to achieve an enhancement of the listening experience with FM radio. The next step of this development was to synchronize the cover art with the music items on air. This was achieved in 2019 and is now standardized as Slideshow by the IEC in Part 6 of IEC 62106.

RDS helped FM broadcasting to be a really successful technology

It was actually RDS that made FM broadcasting very successful and extremely widespread. The RDS technology can be seen as a 'silent revolution' within FM broadcasting. The RDS technology will therefore most probably live as long as FM broadcasting, which will remain the last hybrid broadcasting technology and of which a likely switch-off is impossible to predict at this time, given the fact that still very many cars have not yet a digital radio and the main radio reception mode is still FM/RDS. The life-time of a car is nowadays 10 to 15 years. In many new cars the radio is not only an integral part of the dashboard and but also an integral part of a complete infotainment system. An upgrade to digital radio reception in those cars is possible, but not yet very popular given the technical difficulties and the labor cost involved. Therefore, FM broadcasting will still be there in 2030 and even later. Any earlier switch-off is just not possible apart from already partially done in Norway and planned for Switzerland as from 2025.

Digital Radio progresses only slowly - but then RDS can well support the transition

The RDS Forum is pro digital radio, even if it maintains FM/RDS. It believes that the transition to digital radio cannot be avoided, even if it will take a very long time. The long transition makes it very complex for modern car radios to achieve radio service following when the drive is over a large distance and includes neighbouring countries, where the development status of the digital radio network is not advanced. Frequent switching between FM and DAB is then needed, in both directions, and without user intervention, hopefully. Not to annoy the end user, broadcasters will have increasingly to use the data features that are common between RDS and digital radio, and there are quite already quite a few, mostly copied from RDS. If this is well done, the transition could be smooth and the RDS Forum has already studied all the issues that will facilitate the transition to digital radio and has created corresponding guidelines for the broadcasters and the receiver manufacturers to explain those important issues in detail and encourage their implementation.

The RDS Forum is a superb contact network

Since many years the RDS Forum offers to the industry, broadcasters, transmission providers and regulators a superb professional contact network. Today the RDS technology is in the process of being adapted to what mobile FM/RDS radio receivers need today (e.g. linkage to Internet). Thanks to the high level of expertise of its members and cooperation with other Fora, a huge experience has been built over the last decades.

Now the focus is on RDS2

The focus since 2015 is concentrated on RDS2, the innovative RDS enhancement developed by a number of RDS Forum members. The priority was the adaptation of the RDS standard with the new version that includes RDS2 being published in 2018 and now in 2022 the UECP, the Universal Encoder Communication Protocol standardized in IEC 62106-10..

An RDS2 demo was first presented in a public meeting during the first RDS2 Info Day, held in November 2015 in Berlin, where RDS Forum experts explained to 70 radio professionals from 14 countries from all over the world the new developments and possibilities that RDS2 will be able to offer.