Germany Looking to Replace DAB with Superior Technology

27th November 2004

From their article from yesterday with the same title as above, the Media Network Weblog reports:

"In Germany, the Media Council for Berlin and Brandenburg (MABB) has stopped issuing licences for Digital Audio Broadcasting (DAB). In that part of Germany, DAB has not proved popular with the public. Sales of DAB receivers have been below expectations, and consumer satisfaction with reception quality has been low. Especially troublesome is the poor reception of DAB inside buildings, whereas FM signals can still be received. A number of Berlin radio stations have already stopped relaying their FM services on DAB. They have been replaced by other services such as Roadradio (a motoring station), YOYO (a children's station) and the BBC.

The MABB says the technical quality of DAB, which dates from the 1980's and is still based on MPEG 2, has been superceded by superior technology. This view is not shared all across Germany. For instance, in Bavaria and Baden-Württemberg DAB is still being heavily promoted. But the MABB is already looking at the next generation of broadcasting technology such as DVB-H and DMB (Digital Multimedia Broadcasting). This is expected to be demonstrated on a large scale at the Internationale Funkaustellung 2005 in Berlin."

As I've explained in the article for the forthcoming Ofcom DAB spectrum consultation, DAB is basically late-1980s technology trying to do a job in the 21^st century, and it's not really up to the job. Since DAB was designed in the late-1980s the DAB specification has stagnated while component technologies that go to make up a digital communications system like DAB have progressed rapidly. The following table compares the relative efficiencies of the most important component technologies that go to make up a digital radio system:

System	Relative Efficiency of Audio Codec	Relative Spectral Efficiency	Overall Relative Efficiency
DVB-H	2.5	2.01	5.03
DMB	2	1.11	2.22
DAB	1	1	1

In other words, DVB-H can carry 5 times as many stereo stations at the same level of audio quality and in a given amount of spectrum as DAB, and DMB can carry 2.22 times as many stereo stations at the same level of audio quality and in a given amount of spectrum as DAB. And the figures for DVB-H's relative spectral efficiency are pessimistic, so the actual spectral efficiency for DVB-H should be significantly higher than that shown above, because the above figure for DVB-H is based on bit error rates (BERs) for video codecs, which require far lower BERs than audio codecs to operate reliably. To see calculations for the above figures, click here.

Also, it is unlikely that DAB will be able to be reliably received on mobile phones, whereas due to the far higher strength of the error correction coding schemes on DMB and especially DVB-H, mobile phone reception is possible -- in fact, DMB and DVB-H were both designed specifically to enable mobile phone reception.

The decision made in Germany follows decisions to ditch DAB in Canada and Ireland "leap-frogging" DAB, with both going for superior modern digital broadcast systems.

27th November (Edited 2nd December)