Glossary
Glossary 
•Antenna
A device that collects and radiates electromagnetic waves. Includes a satellite dish and abroadband antenna.
•Forward Error Correction(FEC)
A system of error control for data transmission.
•Frequency
The number of cycles or events per one second, which is expressed in the unit of Hertz(Hz).
•Intermediate Frequency(IF)
A frequency to which a carrier frequency is shifted as an intermediate step in transmission or reception.
•Low Noise Block(LNB) Downconverter
A low noise microwave amplifier and converter which downconverts a range of frequencies to IF range.
•Packet Identifier(PID)
A set of numbers that idenitifies transport stream packets containing data from a single data stream.
•Polarisation
Characteristic of an electromagnetic wave determined by the orientation of the electricfield vector.
•Quaternary Phase Shift Keying(QPSK)
•Service
A channel to which a decoder or TV is tuned.
•Transponder
An automatic device that receives, amplifies and retransmits a signal on a different frequency.
E4
