- Television and audio broadcasting are undergoing a continuous process of
integration and digitalization. Signal complexity increases due to the more
complex information that willl be transported by the relevant technologies (e.g.
DVB, DAB) as well a tighter connection between internet and television / audio
broadcasting.
- The underlying digital technologies impose new stringent requirements
regarding towards synchronization. Tighter synchronization performances are
indeed needed to achieve the requested Quality of Service. One way of doing that
is by the widespread of rubidium frequency standard.
- The main forms of digital radio and television are Digital Audio
Broadcasting (DAB), Digital Video Broadcasting (DVB), DVB-S (Digital Video
Broadcasting–Satellite) and Digital Video Broadcasting - Terrestrial (DVBT).
These new broadcasting forms make all use all synchronous transmission
technologies at various levels both for the carriers and for the signals.
- DAB - Digital Audio Broadcasting is a digital
transmission system for radio broadcasting, using dedicated receivers. In
addition to audio data (voice and music) DAB allows to the transmitting of video
and information data at low data transfer rates as well as value-added services
such as a news-ticker.
- DVB – Digital Video Broadcasting group was created
in order to establish a technical framework for the introduction of digital
broadcasting systems to suit the whole range of delivery mechanisms, including
cable, satellite, terrestrial and MMDS (multimedia digital services). DVB has
already developed a coherent set of methods to bring digital television to home.
The DVB standard itself is a generic term for various technical specifications
and various transmission methods such as DVBT (terrestrial – COFDM technology),
DVB-S (satellite – QPSK), and DVB-M (cable – QAM). In the initial phase DVB
focuses on stationary applications such as home television. In a later second
phase the extensive usage in mobile applications is planned. Furthermore, the
integration of manufacturers, regulators, network operators, and broadcasters
create a wide basis of acceptance.
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