Advantech L-Band Satellite Modulator, Инструкция по установке и эксплуатации

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Glossary
Term Description
Mbit/s Million bits per second.
MCPC Multiple Channels Per Carrier.
MIB Management Information Base: A type of database used to manage the
devices in a communications network. It comprises a collection of
objects in a (virtual) database used to manage entities (such as routers
and switches) in a network.
MP@ML Main Profile at Main Level: A subset of the MPEG-2 standard, which
supports digital video storage (DVD etc.) and transmissions up to 15
Mbit/s over various mediums.
MP@HL Main Profile at High Level: A subset of the MPEG-2 standard, which
supports digital video storage (DVD etc.) and transmissions up to 80
Mbit/s over various mediums.
MPEG Moving Pictures Experts Group: The name of the ISO/IEC working group
which sets up the international standards for digital television source
coding.
MPEG-2 Industry standard for video and audio source coding using compression
and multiplexing techniques to minimise video signal bit-rate in
preparation for broadcasting. Specified in ISO/IEC 13818. The standard is
split into layers and profiles defining bit-rates and picture resolutions.
Msymbol/s (Msym/s) Mega (million) Symbols per second (10
6
Symbols per second).
Multiplex A number of discrete data streams (typically 8 to 12), from encoders,
that are compressed together in a single DVB compliant transport stream
for delivery to a Modulator.
Mux Multiplexer: Transmission Multiplexer: receives EMMs from the ACC, ECMs
from the BCC, video/audio data from the encoders, and the SI stream
from the SIC. It then multiplexes them all into a single DVB-compliant
transport stream, and delivers the signal to the uplink after modulation.
The Multiplexer also contains the cypher card, which scrambles the
services according to the control words supplied by the BCC.
NTSC National Television Systems Committee: The group, which developed
analogue standards used in television broadcast systems in the United
States. Also adopted in other countries (e.g. Mexico, Canada, Japan).
This system uses 525 picture lines and a 59.97 Hz field frequency.
NVOD Near Video On Demand: Method of offering multiple showings of movies
or events. The showings are timed to start at set intervals, determined by
the broadcaster. Each showing of a movie or event can be sold to
subscribers separately.
ODU Outdoor Unit
OFDM Orthogonal Frequency Division Multiplex: A modulation technique used
for digital TV transmission in Europe, Japan and Australia; more spectrally
efficient than FDM. In OFDM, data is distributed over a large number of
carriers spaced apart at precise frequencies. The carriers are arranged
with overlapping sidebands in such a way that the signals can be
received without adjacent channel interference.
OPPV Order ahead Pay Per View: An advance purchase of encrypted one-
time events with an expiry date.
B-8
SBM75e Series Modulator Installation and Operation Manual