Wegener DTV 720 User Manual page 12

DTV 720 U ' M
SER S ANUAL
PAT
PCR
PID
PMT
Program
PSI Tables
PSIP
RAM
RF
TMRA
Transport Stream
(or MPEG Transport
Stream)
Warning
800043-01 Rev. C
Table 1.2: Glossary of Terms
Term
Program Allocation Table. Master table which identifies all the Programs in
the Transport Stream. It associates Program numbers to the PIDs bearing
the associated Program's PMT.
Program Clock Reference. Time-base signal used to synchronize transport
stream data.
Packet Identifier. The unique Transport Stream packet identifier assigned to
each constituent data stream within the Transport Stream. Also, in this doc-
ument, "PID" is used to designate the stream itself.
Program Map Table. Table for a given Program identifying all the PIDs for its
PCR, video, audio, and user data streams.
In the MPEG hierarchy, a grouping of related audio, video, or generic data
PIDs sharing a common PCR time base and (usually) sharing a common
schedule. See PMT.
Program-Specific Information Tables. A group of information-bearing tables,
each borne by well-known PIDs, regularly transmitted in the Transport
Stream. See also "PAT" and "PMT". Also, ISO 13818-1 gives a thorough
description of these and other Tables.
Program and System Information Protocol - a method for transporting digital
television system information and electronic program guide data.
Random access memory. A general term for all memory volatile memory
types out of which application software executes and into which its vari-
ables, state information, and messages are stored. RAM is also used to
designate the volatile storage used by the Transport Demux and decom-
pression devices.
Radio frequency
Maximum Recommended Ambient Temperature, the highest operating tem-
perature for which the unit is rated
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, and padding in the form of null packets.
A condition or notification of a condition that may compromise the proper
performance of your DTV 720
Definition
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