Glossary
Instruction Manual: TT1260 Standard Definition Professional Receiver/Decoder Page A-9
ST.TM.E10100.1
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 a nd 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 construc tively 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 Mbit/s. 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 o r other
authorising 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 passwo rd 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.
Spatial Redundancy Information repetition due to areas of similar luminance and/or chrominance characteristics wi thin a single frame.
Removed using DCT and Quantisation (Intra-Frame Coding).
SPI Synchronous Parallel Interface.
Statistical Redundancy Data tables are used to assign fewer bits to the most commonly occurring events, thereby reducing the overall
bit-rate. Removed using Run Length Coding and Variable Length Coding.
TAXI Transparent Asynchronous Tx / Rx Interface: A proprietary high-speed data interface.
TCP / IP Transmission Control Protocol/Internet Protocol: A set of communications protocols that may be used to
connect different types of computers over networks.
TDM Time Division Multiplex: One common, communications channel carrying a number of signals, each with its own
allotted time slot.
TDT Time and Date Table: Part of the DVB Service Information. The TDT gives information relating to the present time
and date.
Temporal Redundancy Information repetition due to a reas of little or no movement between successive frames. Removed using motion
estimation and compensation (Inter-Frame Coding).
Time-stamp A term that indicates the time of a specific action such as the arrival of a byte or the presentation of a present ation
unit.
TOT Time Offset Table: This optional SI table supports the use of local offsets as well as the UTC time/date
combination.
The purpose of the table is to list by country the current offset from UTC and the next expected change to that
offset (to track when daylight saving occurs).
The offset resolution is to within 1 minute over a range of ±12 hours from UTC.
Transport Stream A set of packetised elementary data streams and SI streams, which may comprise more than one programme, but
with common synchronisation and error protection. The data structure is defined in ISO/IEC 13818-1 [1] and is the
basis of the ETSI Digital Video Broadcasting standards.
Transport Stream Packet
Header A data structure used to convey information about the transport stream payload.
TS Transport Stream.