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- Earth station
- Generic term for any transmitting or receiving station for satellite transmissions.
- Energy per bit to noise density ratio.
- Edge of coverage
- Limit of a satellite's defined service area. In many cases, the EOC is defined
as being 3 dB down from the signal level at beam centre, though reception may
still be possible beyond the -3 dB point.
- Property of an antenna: typically 55-70% for an SNG antenna.
- Effective isotropic radiated power: defines the total system power in dBW;
describes the strength of the signal leaving the satellite antenna or the uplink
antenna, and is used in determining the C/N and S/N.
- Upward tilt of an antenna measured in degrees, required to point accurately
the antenna at the satellite; angle of tilt (inclination) of an uplink antenna;
the angle of the direct path to the satellite above the horizon.
- Electromagnetic compatibility: generic term for a Directive of the EU covering
electromagnetic interference (EMI).
- Electromagnetic interference.
- Device used to digitally compress the video and audio signals for transmission.
- Process of encoding or scrambling television signals so that unintended audiences
are unable to view the signal.
- The useful information content of a signal.
- Ephemeris data
- Data regularly published by satellite operators describing cyclical influences
of gravity from the Sun and the Moon, as well as solar radiation. These all affect
the positioning of the satellite.
- Error correction
- Process where bits are added in the modulation of a digital signal to correct
for errors in transmission.
- European Technical Standards Institute: established in 1988 on the joint initiative
of the EU and the CEPT to produce technical standards for telecommunications across
- Generic term for the combination of an analogue modulator and upconverter,
which provides the drive signal to the input of an HPA.