CDM-625 Advanced Satellite Modem
Revision 1
Introduction
MN-0000036 (Ref MN/CDM625.IOM)
1.7.3
Data Interfaces
Primary Data
(4 selectable modes)
RS-422/EIA-530 DCE (Rates up to 14 Mbps)
(also supports X.21 DCE & DTE and 8k ESC orderwire for IDR)
V.35 DCE (Rates up to 14 Mbps)
LVDS serial (Rates up to 25 Mbps)
HSSI serial (Rates up to 25 Mbps)
25-pin D-sub (female)
G.703 (Tx In, Drop Out,
Insert In, Rx Out)
1.544 Mbps T1 (Balanced 100
Ω
)
6.312 Mbps T2 (unbalanced 75
Ω
or balanced 110
Ω
)
2.048 Mbps E1 (unbalanced 75
Ω
or balanced 120
Ω
)
8.448 Mbps E2 (unbalanced 75
Ω
)
Note
: All Drop and Insert modes are a
FAST
option.
9-pin D-sub (female)
or BNC (female)
ASI
Uses G.703 (Tx In, Rx Out) ports
BNC (female)
Auxiliary G.703 (used for
Quad D&I modes)
Two additional 1.544 Mbps T1 ports (Balanced 100
Ω
)
Or:
Two additional 2.048 Mbps E1 ports (balanced 120
Ω
)
Note
: All Drop and Insert modes are a FAST option.
9-pin D-sub (female)
External Reference In/out
As an input:
1, 2, 5 or 10MHz -6dBm to +10dBm (nominal 50/75
Ω
)
As an output:
10MHz, 2.7 volts peak-to-peak +/- 0.4 volts, low impedance output
BNC (female)
Overhead Data
IDR BWA Inputs/Outputs
ADPCM Audio Interface
RS-422 octet clocks for IDR ESC & IBS
RS-422 IDR 64 kbps ESC data & clock
IDR BWA Inputs/4 backward alarm Form C relay outputs
2 audio channels, each occupying 32 kbps bandwidth as part of IDR overhead
or as a 64 kbps primary data rate option.
600
Ω
balanced – 0 dBm0 nominal, -6 to +8 dB, 2 dB steps
44-pin High-density
D-sub (male)
Modem Alarms
Relay outputs (Tx, Rx & unit faults)
Demodulator I & Q test outputs (constellation)
Demodulator Rx Signal Level output (0 to 2.5 volts)
External carrier off input
15-pin D-sub (male)
ESC (Overhead)
Standard IBS ESC interfaces
RS-232/485 High Rate ESC data
RS-232/485 ESC++ data
9-pin D-sub (female)
Remote Control
RS-232 or RS-485 modem control and monitoring
9-pin D-sub (male)
PMSI Interface
Pre-mapped Symbol interface (used by DoubleTalk® Carrier-in-Carrier®
function)
9-pin D-sub (female)
1:1 Control
Control interface for CRS170A/CRS180 1:1 Redundancy unit
9-pin D-sub (male)
Ethernet
4 ports of 10/100 baseT auto-sensing full/half duplex Ethernet
RJ-45
1.7.4
Automatic Uplink Power Control
Operating Mode
Requires Closed Network Framed mode (EDMAC, D&I++, Enhanced D&I, or ESC++) for transport of
Eb/No information from remote modem (EDMAC can be enabled or disabled)
Target Eb/No range
0 to 14.9 dB at remote demod (default is 4.0 dB)
Max AUPC range
0 to 9 dB (default is 3 dB)
Monitor functions
Remote demod Eb/No
Tx power level increase
(front panel or via remote control interface)
1–15
