Auto Search
IRD feature that automatically locates and stores all satellite channels into its memory

Astra
Operated by the Socitete Europeenne des Satellite (Luxembourg), the Astra Satellite family(1A-E) provides about 56 transponder for analogue and digital direct-to-home transmission channels of Audio and TV-programmes in Europe.

API
Abbreviation for Application Program Interface.

ATM
Abbreviation for Asyncronous Transfer Mode.

Bandwidth (broad/narrow band)
The speed of data transmission depends on the available bandwidth of the transmission channel. Narrow band channels provide data transfer rates of 100 kbit/s whereas broadband channels allow transfer of >1 Mbit/s.

Back channel
To enable interactive and Pay-TV services, a direct communication channel between the broadcaster or service provider and the consumer is needed. Normally this "Back"-or "Return channel " is realised via the normal telephone line.

BAT
Abbreviation for Bouquet Association Table.

Bit/byte
One bit is the smallest discrete element in a binary system. Eight bits comprise one byte.

Bitrate
The rate (in Mbit/s) for transmission of serial digital information.

Bouquet
A collection of services marketed as a single entity.

C-Band
The 3,7 to 4,2 GHz range in the frequency band.

Coaxial Cable
A type of cable used to transport high frequency signals e.g. from the LNB to the satellite receiver.

CD-ROM
Compact Disc- Read Only Memory. The CD-ROM is an optical storage device, which is not erasable. The storage capacity of a CD-ROM is 650 Mbytes.

Common Interface
Describes a hard and software architecture for Conditional Access Systems whereby the generic "host" set-top-box is not dedicated to one particular encryption system. Consumers use detachable modules, which allow them to receive encrypted services they pay subscription fee for. The interface between host set top box and module is standardised (PCMCIA-Interface) so that the same set top box can be used to handle a variety of encryption systems.

Conditional Access (CA)
A system for scrambling and encryption signals in order to deny access to programmes for those viewers who have not paid subscription fees for these programmes (e.g. Videoguard, Eurocrypt).

CRC
Abbreviation for Cyclic Redundancy Check.

DAVIC
The Digital Audio Video Council, an international group which met for the first time in 1994, is set up to define the interfaces and protocols necessary to support delivery of international digital video services.

Decoder
A device that restores a signal to its original form after it has been encoded.

Demodulator
A device that extracts digital information from transmitted carrier waves.

Digital
Any kind of analogue information ( speech, pictures, text, etc.) can be scanned and transformed into binary digits.

DAB
Digital Audio Broadcasting is a digital transmission system for radio broadcasting, using dedícated receivers. In addition to audio data (voice and music) DAB allows as well to transmit video and information data at low data transfer rates.

Digital compression
A way of reducing the number of bits in a digital signal by using mathematical algorithms to eliminate redundant information thereby reducing the space the signal occupies when being transmitted or recorded.

DVB
Digital Video Broadcasting group was created to establish a technical framework for the introduction of digital broadcasting systems to suit the whole range of delivery mechanisms, including cable, satellite, terrestrial and MMDS. DVB has already developed a coherent set of methods to bring digital television to home.

DBS
Direct Broadcasting satellite is an american transmission system based on high-powered Ku-band satellites (120-200 watts per transponder). The signals can be received using a small 18 inch dish. Currently there are four DBS-Services in operation in the US (Primestar, DirecTV/USSB and EchoStar).

DTH
Direct-To-Home. Used to denote satellite TV signals received by a single household via an individual dish installation.

Dish
The dish collects, reflects and focuses the satellite signal into the LNB.

Downconverter
A device that reduces the high-frequency signal to a lower, intermediate range. The three types of downconversion are signal, dual and block downconversion.

Downlink
Term used to describe the retransmitting of signals from a satellite back to Earth.

Download
The download function enables service providers to update the system software of their Set Top Boxes via their transmission channels.

EBU
Abbreviation for European Broadcasting Union

ECM
Entitlement Control Messages. Are private Conditional Access information which maintain the ordered authorization.

EIT
Abbreviation for Event Information Table

E-mail
A system for transmitting messages or information through an electronic communication network.

Encoder
A device that encodes the signal before transmission.

EMM
Entitlement Management Messages. Are private Conditional Access information which specify the authorization levels or the services of specific decoders. They may be addressed to individual decoder or groups of decoders.

ETS
Abbreviation for European Telecommunication Standard.

ETSI
Abbreviation for European Telecommunication Standard Institute.

Error Correction Mode
Due to the high compression factors used in MPEG decoding of digital signals, Error Correction Modes become necessary, to avoid any significant loss of bit information during signal transmission. Commonly applied are Reed-Solomon Codes. The efficiency of error correction modes are defined by the so called bit error rate (BER), which gives the quotient received bits to the total number of transmitted bits in a specified time period.

Event
A grouping of elementary broadcast data streams with a defined start and end time belonging to a common service, e.g. first half of a football match, News Flash, a talk show.

FEC
Abbreviation for Forward Error Correction. Correction to a certain extent, of faulty bits in the received signal.

Frequency
The property of a signal measured in cycles per second(=Hz).

Geostationary
Fixed orbit, approximately 36.000 km above the Earth´s equator. Satellites parked in this orbit travel at the same speed as the rotation of the Earth.

Gigahertz
One billion cycles per second (1.000.000.000 Hz/s). Signals above one gigahertz are called microwaves.

HDTV
Abbreviation for High Definition Television.

Hertz
Cycles per second

IEC
Abbreviation for International Electrotechnical Commission.

IRD
Abbreviation for Integrated Receiver Decoder. A Set Top Box receiver with a built in descrambler for decoding pay-TV services.

ISO
Abbreviation for International Organisation for Standardisation.

ITV - Interactive Television
Based on a backchannel interactive TV enables the consumer e.g. to select his individual TV programme at any time or to take part in game shows although being at home. The acceptance of interactive TV is presently tested in various pilot runs all over the world.

MCPC
Multiple Channel Per Carrier.

Megahertz
Millions of cycles per second.

MMDS - Microwave Multichannel Distribution System
A distribution service for TV signals using microwave transmissions. Also called multichannel video distribution system (MVDS). In the US, it is called "wireless cable".

Modem
Modulator/Demodulator. A device for converting digital data to audio tone and (vice versa) for transmisson on an analogue channel.

MPEG - Motion Picture Expert Group
Body established by the International Standards Organisation to provide the basis for a picture coding and compression system. MPEG first designed a standard - MPEG -1 - for bitrates of around 1.2 Mbit/s, primarily for carring VHS-quality video on compact disc based multimedia systems. MPEG-2 is a video compression standard being developed for bitrates from 3 - 15 Mbit/s.

MPEG-2
MPEG-2 is a video compression standard being developed for bitrates from 3 - 15 Mbit/s.

Network
A collection of MPEG-2 Transport Stream multiplexes transmitted on a single delivery system, e.g. all digital channels on a specific cable system.

NTSC
The colour TV system established by the US National Television Standards Committee which is used in North America, Japan and their dependents. NTSC produces interlaced 525 line 30 frame/s pictures.

NVOD - Near Video On Demand.
Term properly describing movie service, but now generally referring to all types of near-on-demand services where viewers are able to order and see a given program of an individual basis at a given time interval.

PAL - Phase Alternation Line
A colour TV system, developed in Germany, which is used in most of Europe, Africa, Australia, and South America. Pal produces interlaced 625 line, 25 frame/s pictures.

PALplus
PALplus is the name of a strategy group formed in 1989 to develop an enhanced terrestrial transmission system compatible with conventional PAL. The group, made up of German, Austrain, Swiss and British broadcasters as well Philips, Thomson, Grundig, Nokia, Sony and Samsung, set itself the task of enhancing the PAL signal by developing the 16:9 letterbox format, increasing the useable luminance bandwidth, reducing cross-colour artifacts, working on echo cancellation and improving sound.

Pay TV
Encrypted TV programmes, which can only be accessed by subscribers, using entitled smard cards of the broadcasters. Generally Pay TV is distiguished into two categories:

1. Pay per Channel
   Customers subscribe on a monthly basis a package of TV-channels.
   
2. Pay per View
   Customers pay for viewing one single movie or e.g. sport event which is selected individually from the TV channels. The smard card registers the access to the programme in order to charge the customer for the selected service.

PID - Packet Identifier
PID is a code used for identifying of the components that forms a particular service in the transmitted datastream.

Point-to-Multipoint
A connection between a service provider and a number of receivers. (E.g. PPV service)

Point-to-Point
A (temporary) separate connection between a service provider and one receiver. (E.g. VOD service).

PSTN
Abbreviation for Public Switched Telephone Network.

QAM
Quadrature Amplitude Modulation. Modulation standard used for cable transmission.

QPSK
Quadrature Phase Shift Keying. Modulation standard used for satellite transmission.

RAM
Random Access Memory. A memory used to store temporary data. The data will be lost when power is swiched off.

RS-250
A serial communication standard used in PC's.

SAS - Subscriber Authorisation System
The SAS is responsible for generating the actual entitlement messages, following the specifications of the encryption standard used.

SCART
Connector-standard used for TV/VCR-devices. Also referred to as "Euro-connector".

SCSI
Parallell PC connection-standard used for high speed transmission (CD-ROM, Hard Disk, etc.).

SECA
Abbreviation for Societé Européene de Controle D'Access

SECAM - Sequentiel Couleur a Memoire
The colour TV standard developed in France, also used in Eastern Europe, and parts of the Middle East and Africa. SECAM produces interlaced 625 line, 25 frames/s picture.

Service
A sequence of programmes under the control of a broadcaster which can be broadcast as part of a schedule.

Service Information
Service Information data is a part of all the EPG data.

Service provider
A company that collects the contents from a number of program/content providers and distributes the services to customers.

Set Top Box
A Set Top Box is a device, which enables the owner of analogue TV sets to receive digital TV signals

SI
Service Information. Service Information data is a part of all the EPG data.

Smart Card
A credit Card-size card contains updateable magnetic or chip memory, used for accessing encrypted TV services, e.g. when inserted in the decoder.

SMS
Subscriber Management System (other names: CMS,Customer Care and Billing System). The SMS is a part of a technical chain, referred to as the entitlement control chain. The SMS contains all customer relevant information and is responsible for keeping track of placed orders, credit limits, invoicing and payments, as well as the generation of reports and statistics.