Tektronix MTD200, Руководство пользователя

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Measurement Functions
2–6
MTD200 MPEG Test Decoder User Manual
Sync_byte_error (1st priority)
Each packet of the transport stream is preceded by a header consisting of four
bytes. The first byte of the header is the synchronization byte (SyncByte), whose
content is always the hexadecimal value 0x47. In the MPEG-2 decoder the
SyncByte serves for synchronization with the packetized transport stream. If the
SyncByte is missing or contains errors too often, the decoder will not be able to
synchronize to the transport stream.
The MPEG test decoder checks the SyncByte of every packet in the transport
stream for correct contents.
In the DVB Measurement Guidelines (ETR290), the preconditions for a
SyncByte_Error message are set as follows:
SyncByte ERROR is signaled if
the content of the synchronization byte in the TS header does not equal 0x47 (hexade-
cimal)
An error of this type is indicated by the LED labeled SYNC lighting (line of
LEDs at front panel). Additional information on the fault triggering the
SyncByte error message (SINGLE = single error or BURST = Burst error) can
be obtained from the monitoring report.