TANDBERG E5780, Справочное руководство

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Glossary
Page A-4 Reference Guide: evolution 5000 E5780 and E5782 Encoder
ST.RE.E10135.4
Downconvert The process by which the frequency of a broadcast transport stream is shifted to a lower frequency range.
DPCM Differential Pulse Code Modulation: An audio digitisation technique that codes the difference between samples
rather than coding an absolute measurement at each sample point.
DRM Digital Rights Management where the rights to view or copy the material is defined and enforced. This is similar
to Controlled Access (CA) but in general, no smartcards are used
DSNG Digital Satellite News-Gathering.
DSP Digital Signal Processor.
DTE Data circuit Terminating Equipment: A communications device that originates (is the source) or is the end
receiving unit (destination) of signals on a network. It is typically a terminal or computer.
DTH Direct-To-Home. The term used to describe uninterrupted transmission from the satellite directly to the
subscriber, that is, no intermediary cable or terrestrial network utilised.
DTS Digital Theater Systems: A motion picture digital sound system.
DVB Digital Video Broadcasting: A European project that has defined transmission standards for digital broadcasting
systems using satellite (DVB-S), cable (DVB-C) and terrestrial (DVB-T) medium, created by the EP-DVB group
and approved by the ITU. Specifies modulation, error correction, etc. (see EN 300 421 for satellite, EN 300 429 for
cable and EN 300 744 for terrestrial).
DVB SI Digital Video Broadcasting Service Information.
DVB-PI DVB-Physical Interfaces
Earth Technical Earth: Ensures that all equipment chassis within a rack are at the same potential, usually by
connecting a wire between the Technical earth terminal and a suitable point on the rack. This is sometimes known
as a Functional earth.
Protective Earth: Used for electric shock protection. This is sometimes known as a safety earth.
EBDU
Encapsulated Bitstream Data Unit is a section of VC-1 bitstream that is self-contained and has been
encapsulated with a start code.
EBU European Broadcast Union.
ECM Entitlement Control Message.
EDI
Ethernet Data Input
EIA Electronics Industries Association (USA) .
EIDU Encapsulated IDU that is an IDU with a start code and, in some cases, an end code to define the IDU within a
continuous bitstream.
EIT Event Information Table: Equipment: A component of the DVB-Service Information (SI) stream generated within
an Encoder, containing information about events or programmes such as event name, start time, duration, etc.
System: EIT (Present/Following) contains the name of the current and next event. It may include an optional
descriptor (synopsis) giving brief details of content. EIT (Schedule) is used to produce a full EPG. The EIT is the
only DVB-SI table, which can be encrypted.
Elementary Stream A generic term for a coded bitstream, be it video, audio or other.
EMC Electromagnetic Compatibility.
EMM Entitlement Management Message.
Encryption Encoding of a transmission to prevent access without the appropriate decryption equipment and authorisation.
EPG Electronic Programme Guide: On-screen programme listing using thumbnail pictures and/or text.
Ethernet The most widely used local area network (LAN) defined by the IEEE as the 802.3 standard. Transmission speeds
vary according to the configuration. Ethernet uses copper or fibre-optic cables.
ETS European Telecommunications Standard.
ETSI European Telecommunications Standards Institute.
FCC Federal Communications Commission.
FDM Frequency Division Multiplex: A common communication channel for a number of signals, each with its own
allotted frequency.
FEC Forward Error Correction: A method of catching errors in a transmission. The data is processed through an
algorithm that adds extra bits and sends these with the transmitted data. The extra bits are then used at the
receiving end to check the accuracy of the transmission and correct any errors.
FFT Fast Fourier Transformation: A fast algorithm for performing a discrete Fourier transform.