Ericsson MX8400, Справочное руководство

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Glossary
STB Set-Top Box: A box that sits on top of a television set and is the
interface between the home television and the cable TV company.
New technologies evolving for set-top boxes are video-on-demand,
video games, educational services, database searches, and home
shopping. The cable equivalent of the IRD.
SFN Single Frequency Network: The SFN technique allows large
geographic areas to be served with a common transmission
multiplex. All transmitters in the network are synchronously
modulated with the same signal and they all radiate on the same
frequency. Due to the multi-path capability of the multi-carrier
transmission system (COFDM), signals from several transmitters
arriving at a receiving antenna may contribute constructively to the
total wanted signal. The SFN technique is not only frequency
efficient but also power efficient because fades in the field strength
of one transmitter may be filled by another transmitter.
SI Service Information: Digital information describing the delivery
system, content and scheduling (timing) of broadcast data streams.
DVB-SI data provides information to enable the IRD to automatically
demultiplex and decode the various streams of programmes within
the multiplex. Specified in ISO/IEC 13818[1]. (DVB)
Single Packet Burst
Mode A burst of ASI bytes (either 188 or 204, depending on packet length)
is contiguously grouped into an MPEG-2 transport stream packet.
Stuffing data is added between the packets to increase the data rate
to 270 Mbps. See DVB Document A010 rev. 1, Section B3.3, (ASI)
Layer-2 Transport Protocol.
Smart Card A plastic card with a built-in microprocessor and memory used for
identification, financial transactions or other authorizing data
transfer. When inserted into a reader, data is transferred to and from
the host machine or a central computer. It is more secure than a
magnetic stripe card and it can be disabled if the wrong password is
entered too many times. As a financial transaction card, it can be
loaded with digital money and used in the same way as cash until
the balance reaches zero. The file protocol is specific to its intended
application.
SMATV Satellite Mast Antenna Television: A distribution system, which
provides sound and television signals to the households of a
building or group of buildings, typically used to refer to an apartment
block.
SMPTE Society of Motion Picture and Television Engineers.
SMS Subscriber Management System: A system which handles the
maintenance, billing, control and general supervision of subscribers
to conditional access technology viewing services provided through
cable and satellite broadcasting. An SMS can be an automatic (e.g.
Syntellect) system where subscribers order entitlements by entering
information via a telephone. Alternatively, an SMS can be a manual
system, which requires subscribers to speak with an operator who
then manually enters their entitlement requests. Some systems
support multiple SMSs.
SNG Satellite News-Gathering.
SNMP Simple Network Management Protocol.
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