MRC DRS4000, Руководство пользователя и техническое руководство

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6
Theory of Operation 6-1 DRS4000 Receiver User and Technical Manual
Theory of Operation
This chapter provides technical information about the design and
function of the DRS4000 Receiver. This includes descriptions of
the functional modules that make up the system architecture.
If you are not familiar with the product information presented in
“Routine Operation” Chapter on page 2-1 , we recommend that
you review that chapter first.
Here are the topics covered:
Topic Page
System Architecture 6-1
Block Downconverters 6-1
RF Switching Module 6-3
Four-Channel Input Tuner Module 6-3
COFDM Diversity Module 6-3
MPEG Decoder Module 6-4
Processor Module 6-4
Interface Module 6-5
Power Supply 6-5
Packet-Based Switch Module 6-5
6.1 System Architecture
The DRS4000 Receiver is a two-channel or four-channel input,
COFDM diversity system that can support DVB-T and LMS-T
COFDM signals. The receiver is designed to support Standard
Definition (SD) and High Definition (HD) decoding.
Within the system architecture for the DRS4000 Receiver, there
are several key components as shown in the block diagram in
Figure 6-1 on page 6-2 . The standard version product consists of
the following functional modules:
• Block downconverters
• RF switching module
• Four-input channel tuner module
• COFDM diversity module
• MPEG decoder module
• Processor module
• Interface module
• AC to DC power supply
The following sections discuss the technical aspects of each of
these modules.
6.1.1 Block Downconverters
The DRS4000 Receiver can operate with either two or four block
downconverters (BDCs). These block downconverters can be
mounted on towers or buildings and can be directly connected to
antennas. The receiver supports different RF bands between 1.7
and 7.1 GHz.