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Glossary
300 Amethyst III DTV Smart Switch
User Manual
SDI Serial Digital Interface.
SD-SDI 270 Mbps Standard-Definition Serial Digital Interface.
SDT Service Description Table.
A mandatory Digital Video Broadcast (DVB) SI table, that provides
information in the SI stream about the services in the system; for example,
the name of the service, the service provider, etc.
SDTV Simple Definition Television.
SFN Single Frequency Network
A SFN is a broadcast network where several transmitters simultaneously
send the same signal over the same frequency channel. The aim of SFNs
is efficient utilization of the radio spectrum, allowing a higher number of
radio and TV programs in comparison to traditional multi-frequency
network (MFN) transmission. SFN transmission can be considered as a
severe form of multipath propagation. The radio receiver receives several
echoes of the same signal, and the constructive or destructive interference
among these echoes (also known as self-interference) may result in fading.
In wideband digital broadcasting, self-interference cancellation is
facilitated by the OFDM or COFDM modulation method. OFDM uses a
large number of slow low-bandwidth modulators instead of one fast
wide-band modulator. Each modulator has its own frequency sub-channel
and sub-carrier frequency. Since each modulator is very slow, we can
afford to insert a guard interval between the symbols, and thus eliminate
the ISI. Although the fading is frequency-selective over the whole
frequency channel, it can be considered as flat within the narrowband
sub-channel. Thus, advanced equalization filters can be avoided. A
forward error correction code (FEC) can counteract that a certain portion of
the sub-carriers are exposed to too much fading to be correctly
demodulated.
SI Service Information
Digital information describing the delivery system, content and scheduling
/timing of broadcast data streams (DVB).
SMPTE Society of Motion Picture and Television Engineers.
A Standards Organization devoted to advancing theory and application in
motion imaging, including film, television, video, computer imaging, and
telecommunications.
SNMP Simple Network Management Protocol.
SNMP provides a means to monitor and control network devices, and to
manage configurations, statistics collection, performance, and security.
SNMP network management is based on the client and server model. Each
managed host runs a process called an agent. The agent is a server
process that maintains the Management Information Base (MIB) database
for the host. SNMP uses ports 161 and 162.
STS Synchronization Time Stamp
STT System Time Table (ATSC)
T2 See ’DVB-T2’
T2-MI DVB-T2 Modulator Interface