Ericsson MX8400, Справочное руководство

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Operating the Multiplexer using nCompass Control
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Generation of MPEG-2/MPEG-4 Program Specific Information (PSI)
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including
Program Association Table (PAT), Program Map Table (PMT) and Conditional
Access Table (CAT).
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Generation of DVB Service Information (SI).
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Status monitoring of Encoders, Multiplexers.and any other supported equipment
switches.
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Redundancy control for systems with spare Encoders, Multiplexers and
Modulators.
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Configuration and PSI data input either locally, on the nCompass Control user
interface, or via a remote interface.
These functions are described in the appropriate nCompass Control documentation.
4.5 MX8400 Multiplexer Modes of Operation
4.5.1 Introduction
There are two types of multiplexing available with the Ericsson range of equipment.
In the simplest mode of operation, called conventional multiplexing, nCompass
Control allocates a fixed bit rate to each Encoder. The Operator can use the display
from nCompass Control to manually alter an Encoder’s bit rate.
The second system, implemented using Ericsson’s Reflex software, allocates a
group bit rate to a set of Encoders. The MX8400 then apportions the bit rate to the
Encoders according to the requirements of the picture encoding process.
4.5.2 Summary of Multiplexing Modes
4.5.2.1 Conventional Multiplexing
The major features of conventional multiplexing are:
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Uses constant bit rate Encoder.
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Bit rate determined by Operator.
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Bandwidth utilization maximized by the Operator.
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Non-optimum usage of channel capacity in systems with varying picture content.
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Use of fixed bit rate leads to variable picture quality.
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ETSI EN 300 468, “Digital Video Broadcasting (DVB); Specification for Service Information (SI) in
(DVB) Systems”.
2/1553-FGC 101 1014 Uen B 4-6