Worldwide the television industry is currently in the process
of changing from analog to digital technology. MPEG-2 has
now been universally adopted as the main standard for video
compression. Since MPEG-2 does not contain all required metadata,
an information layer needs to be added to the MPEG in order
to transmit it to some end users. Standards have been created
by industry to provide for the methodology of packetizing
MPEG-2 streams and adding encoding information in tables via
data packets to the video packets. The DVB standard has been
approved by the European Community and other industry and
government groups as the standard to accommodate the need
for satellite and terrestrial originated digital television.
This product complies with the DVB ASI specifications as defined
in ETSI TR 101 891 and provides for the ability of computers
to capture, process, and transmit DVB ASI compliant streams.
THE DVB ASI STANDARD
DVB ASI defines a method of digitally transmitting MPEG-2
Transport Streams at 270 mbps and is designed to be transmitted
via QPSK modulation via a Satellite based Router to the home
receiver. It is usually composed of many standard definition
4-6 Mbps streams Multiplexed together with associated audio
streams in various languages into a multi Program Transport
Stream. This is the standard that is usually used to feed
most brands of DVB Modulators. Our DVB Master III Tx device
can be used to create outputs for Video Servers or test equipment
that is compatible with the DVB ASI standard.
Clock Issues: The DVB ASI standard specifies a very accurate
30 ppm clock. The cabling for DVB requires a 75 Ohm Coaxial
Cable with BNC connectors.
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