Radyne ComStream TIERNAN SE4000, Installation And Operation Manual

Page: 154 / 161

SE4000 MPEG-2 Contribution Encoder Glossary
01-0934-401-B
GL-5
I
IBS Intelsat Business Services
IDR Intermediate Data Rate
I/O Input/Output
IEC International Electrotechnical Commission. A Geneva-based organization that
sets international electrical and electronics standards and includes national
committees from over 40 countries.
IEEE International Electrical and Electronic Engineers
IESS INTELSAT Earth Station Standards
IF Intermediate Frequency.
1. A frequency to which a signal wave is shifted locally as an intermediate
step in transmission or reception.
2. The fixed frequency resulting from heterodyning the incoming signal with
a signal from a local oscillator.
IFL Interfacility link. Typically refers to an interfacility link cable used to connect a
low-noise block (LNB) to an IRD. Often this IFL carries power from the IRD to
the LNB.
IF Looptest A diagnostic, troubleshooting, or operational test procedure designed to test
operate satellite equipment by passing video and audio test signals through an
encoder and satellite modulator, looping the output of the modulator to the input
of the IRD, and monitoring the video and audio output of the IRD.
Impedance The total opposition of a device offers to the flow of alternating current.
Measured in Ohms and varies at different frequencies.
Integrated
Receiver/
Decoder Within a satellite downlink system, a piece of equipment used to demodulate
and decode a transport stream.
INTELSAT International Telecommunication Satellite Organization
IRD See Integrated Receiver/Decoder.
ISO International Standards Organization
I&Q Analog In-Phase (I) and Quadrature Signals (Q)
J
J Joule