Standard And Optional Features; Figure 1-2. Block Diagram - Comtech EF Data CDM-710 Installation And Operation Manual

CDM-710 Broadcast Satellite Modem
Introduction
The modem is compact, being 1RU high x 18.65 inches deep with low power consumption. It has
a front panel VFD display and keypad for local configuration and control, although it can be fully
remote-controlled via a RS-485 bus or 10/100 Base-T Ethernet Interface.
A block diagram of the modulator is shown in Figure 1-2.
Data
Data
Depends
Interface
Interface
On
Slot 1
Slot 1
Selected
(Option)
(Option)
Interface
Data
Depends
Data
Interface
On
Interface
Slot 2
Selected
Slot 2
(Option)
Interface (Option)
EXT
External
REF
Reference
EIA-
Remote
EIA-
232/485
Port
232/485
Ethernet
Ethernet
10/100
Ethernet
10/100
BaseT
BaseT
Alarms
Alarms
Alarms
1.1

Standard and Optional Features

The modem operates in DVB-S (QPSK), DVB-DSNG (8-PSK and 16-QAM) and DVB-S2
(QPSK, 8-PSK, 16-APSK, and 32-APSK) modes. The modem is operated from the front panel
using the keypad and display or remote controlled via an RS-232 / RS-485 2/4 Wire bus or
10/100 Base-T Ethernet port located on the base modem.
The modem is available for either 70/140 MHz or L-Band applications. The standard
70/140 MHz Tx-IF port has a BNC female connector that is programmable for either with 50Ω or
75Ω impedance operations. Spectral rolloffs of 20, 25, and 35% are available.
Framer
DVB-S2
DVB-S2
LDPC
LDPC
Future + BCH
Future + BCH
Mode
Mode
& DVB-S &
& DVB-S &
Stream DSNG
Stream DSNG
Adaptation Viterbi+RS
Adaptation Viterbi+RS
FEC
FEC
Keypad
Keypad
uP &
uP
Display
Display
Power
Power
Supply
Supply

Figure 1-2. Block Diagram

1–2
Modulator
Nyquist
Nyquist
Filters
Filters
Mapping
Mapping
Tx
Tx
&
&
Synth
Synth
Pilot
Pilot
Insertion
Insertion
Demodulator & FEC
Rx
Rx
Synth
Synth
Demod
Demod
Decoder
Decoder
&
Revision 9
MN/CDM710.IOM
Tx
70 / 140MHz
Or L-Band
Up
Up
Converter
Converter
Rx
70 / 140MHz
Or L-Band
Down
Down
Converter
Converter
CDM - 710