Microwave Radio Communications SCM4000, Техническое справочное руководство

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Theory of Operation 8-4 SCM4000 Technical Reference Manual
A simplified SCM4000 Modulator block diagram is shown in
Figure 8-2 .
Figure 8-2: SCM4000 Modulator Block Diagram
8.3.6 SCM4000 Demodulator Description
The SCM4000 Demodulator configuration receives 70 MHz, M-
QAM modulated signals from the Modulator via radio and radio
link and converts the data back into its original four channels of
data. The radio link can introduce considerable distortion and
noise that is removed by the Demodulator module.
A simplified SCM4000 Demodulator block diagram is shown in
Figure 8-3 .
POWER SUPPLY
AC/DC
POWER
DISTRIBUTION COMMAND AND
CONTROL AND FRONT PANEL
SCM
MODULATOR
STATUS
DISPLAY KEYPAD
CONTROL
(RS232)
E1/T1
10/100
E1/T1
10/100
RS232/
485
SUM
ALARM
ASI
DS3/E3
ASI
DS3/E3
ASI
SMPTE
MODULATOR
CORE BOARD
IF
OUT
POWER IMB
IF
OUT
1
2
3
INTERFACE BOARD
MICROPROCESSOR
Figure 8-3: SCM4000 Demodulator Block Diagram
8.3.7 SCM4000 Modulator/Encoder
The SCM4000 Modulator/Encoder configuration contains both a
built-in MPEG Encoder and a Modulator. This configuration
provides analog video and audio input access, as one of the four
data input channels, configured for your individual requirements.
A simplified SCM4000 Modulator/Demodulator block diagram is
shown in
Figure 8-4 on page 8-5 .
POWER SUPPLY
AC/DC
POWER
DISTRIBUTION COMMAND AND
CONTROL AND FRONT PANEL
SCM
DEMODULATOR
STATUS
DISPLAY
KEYPAD
CONTROL
(RS232)
E1/T1
10/100
E1/T1
10/100
RS232/
485
SUM
ALARM
ASI
DS3/E3
ASI
DS3/E3
ASI
SMPTE
DEMODULATOR
CORE BOARD
IF IN
POWER IMB
IF IN
1
2
3
INTERFACE BOARD
MICROPROCESSOR