TechniSat DIGITRADIO 3 Operating Manual page 66

7 DAB+ (digital radio) function
7.1 What is DAB+?
DAB+ is a new digital format through which crystal clear sound with no noise can
be heard. In contrast to conventional analogue radio stations, DAB+ can be used to
broadcast multiple stations on one and the same frequency. This is referred to as
an ensemble or multiplex. An ensemble is comprised of the radio station, as well as
several service components or data services which are broadcast individually by the
radio stations. For further information, please visit e.g.
www.dabplus.ch.
7.1.1 Data compression
By doing so, digital radio takes advantage of the properties of human hearing. The
human ear does not perceive sounds that are under a specific minimum volume.
Data that is under the so-called audibility threshold can, therefore, be filtered out.
This is possible since, in a digital data stream, the relevant relative volume for other
units is saved for every unit of information. Moreover, in an audio signal, the louder
components superimposed onto the quieter ones at a specific limit value. All the
sound information below the threshold of hearing in a piece of music can be filtered
out of the signal to be broadcast.
This results in a reduction of data in the data stream to be transmitted, with
no perceptible difference in sound for the listener (HE AAC v2 process as a
supplementary codification process for DAB+).
7.1.2 Audio stream
With digital radio, audio streams are continuous data streams that contain the MPEG
1 audio layer 2 frames and thereby represent acoustic information. This enables
standard radio channels to be broadcast and listened to on the receiver side.
Digital radio not only provides you with radio in excellent sound quality, but also
additional information. This may refer to the programme being broadcast or may be
independent information (e.g. news, weather, traffic, tips).
7.2 DAB+ (digital radio) reception
> Press the MODE button until [DAB] is shown on the display.
If DAB+ is being started for the first time, a complete station scan is
performed. After the scan is complete, the first station is played back in
alphanumeric order.
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www.dabplus.de or