Satellite TV Receivers Glossary

CA
Conditional Access. See CAS.

CAM
Conditional Access Module.

CAS
Conditional Access System - Common name for the decryption system either built (embedded) into the satellite receiver or performed via a CA-module inserted into a receivers CI Slot (Common Interface). CAS systems are normally connected to a smart card reader to allow Pay-TV operators to control subscriber access to encrypted signals.

CI
Common Interface. A standard for using PCMCIA devices to implement different features into a set-top-box. Normally 1 or 2 CI slots are available. Example: CAM modules for Conax or Viaccess decoding.

Clarke Belt
The circular orbit at appr. 35800 km above the equator, where the satellites travel at the same speed as the earth's rotation (Geostationary Orbit) and thus appears to be stationary to an observer on Earth. Named after Arthur C. Clarke who first postulated the idea of geostationary communication satellites.

Coaxial cable
Connecting cable between i.e. LNB and satellite receiver, for transmission of signals received and for supply of power to LNB unit.

Conax
Digital coding/encryption method (See CAS).

D

Data compression/MPEG1/MPEG2
Transmission of the present TV standard (625 lines and 50 Hz picture frequency for a PAL signal) requires a digital data amount of 216 Mbit/s. This would require transmission bandwidths that are not available either terrestrially or via satellite.
Therefore a reduction of the data amount is made through data reduction. In Europe MPEG-2 is the universal standard for data compression. MPEG2 is an extension of MPEG1.

DCF
Double Channel Filter

DiSEqC
Digital Satellite Equipment Control: A digital control signal for controlling the DiSEqC-compatible units (typically one or more switches) of the dish over the coaxial cable.

DTH
Direct To Home - meaning single home installation.

DVB
Digital Video Broadcasting. A digital, universal transmission technique and standard for picture, graphics, sound and text as well as for data of any shape and quality.

E

EPG
Electronic Programme Guide. A graphical user interface generated by a digital receiver and displayed on the user's television screen.

F

Frequency
Physical quantity, indicates the number of cycles per second, measured in Hertz (Hz).

Unit of frequency	Designation	Cycles per second
1 Hz 1 kHz 1 MHz 1 GHz	1 Hertz 1 kilo Hertz 1 Mega Hertz 1 Giga Hertz	1 1,000 1,000,000 1,000,000,000

Frequency range
a) Satellite and LNB:
    11 GHz range from 10.70 GHz to 11.70 GHz (Low Band)
    12 GHz range from 11.70 GHz to 12.75 GHz (High Band)
b) Receiver:
    Intermediate frequency or 1st. IF: 950 to 2150 MHz

FTA
Free To Air. Signals that are not encrypted, and thus freely available to everyone with a Free-To-Air receiver.

G

Geostationary Orbit
See Clarke Belt

H

High Band
The upper part of the Ku-band downlink frequency range, from 11.7 GHz to 12.75 GHz

I

IF
Intermediate frequency.

Intermediate frequency
The frequency range from the satellite cannot be transmitted via a cable and is therefore converted to the intermediate frequency range from 950 to 2050 MHz by the LNB. This allows for transmission and processing in the receiver.

IRD
Integrated Receiver Decoder. An indoor device accepting signals from at least one LNB, which recovers the original signal from the signal delivered by the LNB. It includes a built-in decoder for reception of services that are protected by a Conditional Access System, subject to authorisation from the provider. A plig-in "smart card" is often used for authorisation purposes.

J

K

Ku-band
Used to refer to a range of frequencies that are available for use by satellite communication systems at around 30 GHz for the uplink and 20 GHz for the downlink.

L

LNB/LNC
Low Noise Block Converter. Receiving unit in the dish focus. Converts the satellite frequency range to the intermediate frequency of the receiver.

LOF
Local Oscillator Frequency. Indicated in MHz or GHz, depending on LNB and frequency range received. Received frequency of receiver = transmitter frequency of satellite - LOF.

M

MATV
Master Antenna TeleVision. More household receiving signals from a master antenna.

MFA
Masthead F-connector Amplifier

MFC
Masthead F-connector Combiner

Modulation with 22 KHz
When using universal LNBs: For switching from Low Band to High Band (11.70 GHz to 12.75 GHz).

Modulator
Output terminal on the satellite receiver or video tape recorder, for connection to the TV by means of an aerial cable.

Multifeed
Outdoor unit consisting of a dish and several LNBs for reception of more than one satellites.

N

Noise Figure
A method for quantifying the electrical noise generated by a particular device. The noise figure is the ratio of the noise power at the output of a device to the noise power at the input of the device. Usually expressed in dB.

O

OTA
Over The Air. This normally indicates that an STB supports download of a new software version via 'over-the-air' transmission (satellite or terrestrial). (As opposed to upgrade via an RS232 and a PC)

Outdoor unit
A designation for the equipment mounted outside, i.e. consisting of satellite dish/offset dish and one or more LNBs for reception of signals from one or more satellites, and DiSEqC switches, if any.

P

Power supply
A unit supplying power to electrical devices.
Some electrical devices i.e. LNBs are powered through the coaxial cable to which the receiver supplies a voltage of 14 or 18 Volt.

Polarisation
For better utilisation of the available frequency bands the satellites transmit adjecent programmes, with opposite polarisation (horizontal and vertical or circular left or circular right). Reception of both types of polarisation requires two single LNBs or a V/H-LNB (Universal LNB).

PSU
See Power supply.

Q

QPSK
quadrature phase shift keying
QPSK is a digital frequency modulation technique used for sending data via satellite.

R

Receiver
See satellite receiver

S

Satellite
A designation for the transmitting unit in space. Most often referred to by name and position, e.g. ASTRA 19° East, EUTELSAT 13° East

Satellite dish
A dish-shaped antenna (reflector) made of metal or metallised synthetic material for bunching of electromagnetic waves from the satellite into a focus.

Satellite receiver
The signals received and converted by the LNB cannot be processed by the TV. The satellite receiver processes them, and transmits audio and video signals (AV) to the TV through its outputs.

SCA
Single Channel Amplifier

SCART
A connector on TV sets, VCRs, satellite receivers and other entertainment equipment for transmission of audio (sound) and video (picture) signals (AV).

SCF
Single Channel Filter

SCS
Single Channel Stopfilter

Smart Card Reader
A device that allows insertion of a Pay-TV subscription smart card to allow access to the encrypted services on a Pay-TV operator. Also requires the corresponding CAS to be available.

SMATV
Satellite Master Antenna Television. More households receiving satellite signals from a master satellite antenna.

STB
Set-top-box. A box to 'set on top of your TV-set'. A common term for a satellite-, cable- or terrestrial receiver.

T

TA
Triax Amplifier

TC
Triax Combiner

TCC
Triax Compact Cabinet

TCH
Triax Compact Head-end

TD
Triax Digital

TMA
Triax Masthead Amplifier

TMC
Triax Masthead Combiner

TMS
Triax Multi Switch

Transponder
Carries out the processing of one or more programmes from a satellite, i.e. reception of data from earth station, amplification and radiation/transmission back to earth.

TS
Triax Splitter

U

Universal LNB
A designation for a three-band LNB. For reception of the ranges FFS (10.70 -11.70 GHz), BBS (11.70 - 12.50 GHz) and FFS High Band (12.50 - 12.75 GHz). The total range is divided into two bands:
Low Band: 10.70 - 11.70 GHz; LOF 9750 MHz
High Band: 11.70 - 12.75 GHz; LOF 10600 MHz

V

Viaccess
Digital coding/encryption method (See CAS).