2. Available (secondary) digital radio distribution platforms

This dossier concerns only the final, downstream segment of the digital radio chain, that of delivery to the listener. According to the EBU (European Broadcasting Union), this is the "secondary distribution" segment (figure 2 ). This dossier therefore does not deal with upstream "contribution" segments, between digital radio studios for example, or "primary distribution" between the digital radio studio and the point of transmission on the listener delivery network.

Whether sounds are represented in analog or digital format, they must be transported via distribution platforms that rely essentially on two physical media:

• electromagnetic waves for distribution via a network of terrestrial transmitters...