EchoStar t-222 fta Guida Utente

 

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AC
Alternating Current (ac voltage)

COFDM
Coded Orthogonal Frequency Division 
Multiplex

DC
Direct Current (dc voltage)

DTT
Digital Terrestrial Television

DVB-T
Digital Video Broadcasting - Terrestrial

FEC
Forward Error Correction

FFT
Fast Fourier Transform

Freq
Frequency

FTA
Free-To-Air

GI
Guard Interval

LCN
Local Channel Number

MUX
Multiplex

PID
Packet Identification

QAM
Quadrature Amplitude Modulation

UHF
Ultra High Frequency

VHF
Very High Frequency

Active antenna

An active antenna has a built-in pre-amplifier which means that the 
received signal gets amplified before it is fed to the receiver. The 
advantage of this antenna type is that (longer) antenna cables become 
less vulnerable for interference. This results in better quality audio and 
video.

COFDM

In the DTT area, COFDM is a form of signal transmission as specified by 
DVB-T. The result of the COFDM digital transmission is to provide a 
received picture that is always free of ghosts and noise (snow).

Constellation

A Constellation is a modulation scheme to improve the transmission. 
Known digital frequency modulation schemes are:
QPSK means Quadrature Phase Shift Keying;
QAM16 means 16-state Quadrature Amplitude Modulation;
QAM64 means 64-state Quadrature Amplitude Modulation.

Digital Terrestrial TV

Digital Terrestrial Television or DTT is basically a digital TV signal 
received through a conventional (indoor or outdoor) TV antenna. Digital 
broadcasts give you DVD-quality video and CD-quality audio.

FEC

A recover-signal mechanism which is part of the transmission that gives 
the receiver software the opportunity to correct for missing or corrupted 
data in the received digital signal.

FFT

A modulation mechanism which is part of the transmission used to make 
the transmitted signal less vulnerable for interference.

Frequency band

A frequency band is a range of frequencies which are dedicated to a 
certain usage. In the terrestrial broadcast area, commonly known bands 
are the VHF-band and the UHF-band.

FTA

An unscrambled broadcast which you can view without additional 
equipment and payments to a service provider.

Guard interval

A timing mechanism which is part of the transmission to prevent 
distorted signals due to transmission errors and signal echoes.

Local Channel 
Number

Some service providers transmit a preferred channel order to make sure 
that during a channel search, all channels are re-arranged in a ‘logical’ 
order. If this selection is active, you are not able to move the channels 
according to your personal preferences.