Ericsson MX8400, Справочное руководство

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Glossary
Encryption Encoding of a transmission to prevent access without the
appropriate decryption equipment and authorization.
EPG Electronic Programme Guide: On-screen programme listing using
thumbnail pictures and/or text.
Ethernet The most widely used local area network (LAN) defined by the IEEE
as the 802.3 standard. Transmission speeds vary according to the
configuration. Ethernet uses copper or fibre-optic cables.
ETS European Telecommunications Standard.
ETSI European Telecommunications Standards Institute.
FBAS German for CVBS
FCC Federal Communications Commission.
FDM Frequency Division Multiplex: A common communication channel for
a number of signals, each with its own allotted frequency.
FEC Forward Error Correction: A method of catching errors in a
transmission. The data is processed through an algorithm that adds
extra bits and sends these with the transmitted data. The extra bits
are then used at the receiving end to check the accuracy of the
transmission and correct any errors.
FFT Fast Fourier Transformation: A fast algorithm for performing a
discrete Fourier transform.
FIFO First In, First Out: A data structure or hardware buffer from which
items are taken out in the same order they were put in. Also known
as a shelf from the analogy with pushing items onto one end of a
shelf so that they fall off the other. A FIFO is useful for buffering a
stream of data between a sender and receiver that are not
synchronized - i.e. they not sending and receiving at exactly the
same rate.
FM Frequency Modulation: Analogue modulation procedure
Footprint The area of the Earth’s surface covered by a satellite’s downlink
transmission. Also (generally) the area from which the satellite can
receive uplink transmissions.
FTP File Transfer Protocol: A protocol used to transfer files over a
TCP/IP network (Internet, UNIX, etc.). For example, after developing
the HTML pages for a Web site on a local machine, they are
typically uploaded to the Web server, using FTP. Unlike e-mail
programs in which graphics and program files have to be attached,
FTP is designed to handle binary files directly and does not add the
overhead of encoding and decoding the data.
G.703 The ITU-T standard which defines the physical and electrical
characteristics of hierarchical digital interfaces.
GOP Group of Pictures: MPEG video compression works more effectively
by processing a number of video frames as a block. The Ericsson
AB Encoder normally uses a 12 frame GOP; every twelfth frame is
an I frame.
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