Wegener UNITY4650, Руководство пользователя

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Unity 4650 User’s Manual
800034-01 Rev. A 24 wegener.com
Transport Loss,
Signal Loss, or
Carrier Loss Loss of transport stream, usually because of carrier-tracking loss, for a time period
defined by a non-volatile factory setting. Transport stream can only be "lost" if the IRD
has first passed the "Verified Transport" state at a particular carrier setting with no inter-
vening change to carrier settings because of user (local or network) command or Auto-
mated Recovery.
Transport Rate The data bit-rate of the transport stream, including the packet sync byte.
Transport Settings The unit settings which allow for the detection, demodulation, and synchronization to a
transport stream (e.g. carrier settings such as frequency, data-rate, FEC, modulation as a
group).
Transport Stream
(or MPEG Transport
Stream) A multiplex of several data streams, each of which is borne in transport packets, 188-byte
blocks containing a sync word, header information (including a PID), and payload data.
This multiplex includes PSI data tables, programs, padding, and floating PIDs such as
those used by COMPEL

network control.
Unit Setting That set of user-programmed, non-volatile IRD attributes which identifies: (1) the
intended transport stream source (e.g. RF carrier parameters, ASI port, etc.); (2) the
desired service information (e.g. selected program, audio stream selection, etc.); and
(3) any supporting monitor settings (e.g. RF carrier margin warning zone, etc.). These
attributes are generally programmed as a set, whether from user command or by retrieval
from a Preset entry during Automated Recovery. When the term "unit setting" is used, it
usually denotes the currently active unit setting.
Volatile See Non-volatile (inverse of).
Warning A condition or notification of (1) a condition that may compromise the proper perfor-
mance of your U4650; or (2) any non-alarm condition that should be brought to local
user’s attention.
Table 3: Glossary of Terms
Term Definition