In digital audio broadcasting( DAB), audio data and additional data are multiplexed into a DAB data stream. Such a data stream is divided into three channels for synchronization, the Fast Information Channel( FIC), in which administrative data and additional services are transmitted, and the Main Service Channel( MSC), which contains the audio data and program-associated data( PAD).
The synchronization channel is used for frame synchronization and automatic frequency control. The data rate for the entire DAB data stream is 2.432 Mbit/s, the net data rate with low error protection is 1.824 Mbit/s and the useful data rate is between 1.2 Mbit/s and 1.5 Mbit/s, depending on the mode. This data rate is perfectly adequate for transmitting up to six audio channels with sampling rates of 24 kHz or 48 kHz and a data rate of 384 kbit/s per audio channel.