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Comtech EF Data

Comtech EF Data CDM-625A-EN Advanced Satellite Modem

Comtech EF Data CDM-625A-EN Advanced Satellite Modem

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SKU: CDM-625AEN

COMTECH CDM-625A-EN ADVANCED SATELLITE MODEM

The CDM-625A-EN Advanced Satellite Modem builds on a legacy of providing the most efficient satellite modems. With support for VersaFEC® Forward Error Correction (FEC), the revolutionary DoubleTalk® Carrier-in-Carrier® bandwidth compression, additional rolloffs and advanced packet processing, the CDM-625A provides significant savings under all conditions. This combination of advanced technologies enables multi-dimensional optimization, allowing satellite communications users to:

  • Minimize operating expenses (OPEX)
  • Maximize throughput without using additional transponder resources
  • Maximize availability (margin) without using additional transponder resources
  • Minimize capital expenses (CAPEX) by allowing a smaller BUC/HPA and/or antenna
  • Or, a combination to meet specific business needs

CDM-625A-EN TYPICAL USERS

  • Mobile Network Operators
  • Telecom Operators
  • Satellite Service Providers
  • Government & Military
  • Enterprise
  • Offshore

COMMON APPLICATIONS

  • Mobile Backhaul
  • G.703 Trunking
  • IP Trunking
  • Offshore & Maritime Communications
  • Enterprise
  • Communications on-the-Move
  • Satellite News Gathering

FEATURES

  • DoubleTalk Carrier-in-Carrier bandwidth compression
  • Carrier-in-Carrier Automatic Power Control
  • VersaFEC FEC with Adaptive Coding and Modulation (ACM)
  • 5%, 10%, 15%, 20%, 25% and 35% Filter Rolloff
  • Packet Processor with header compression, payload compression, advanced Quality of Service (QoS) and Managed Switch Mode with VLAN support
  • Integrated 4-port managed Ethernet switch with VLAN and QoS
  • Jumbo frame support
  • Dual Band Capability: 70/140 MHz and extended L-Band (950 – 2250 MHz) in same unit
  • Data Rate: 18 kbps to 25 Mbps
  • Symbol Rate: 18 ksps to 12.5 Msps
  • Modulation: BPSK, QPSK/OQPSK, 8PSK/8-QAM, 16-QAM
  • FEC: Viterbi, Sequential, Concatenated Reed Solomon, TCM, Turbo Product Code (TPC) (IESS-315 Compliant), LDPC Code and VersaFEC (low-latency LDPC)
  • Widest Range of data interfaces: EIA-422/530, V.35, G.703 T1, G.703 E1, G.703 T2, G.703 E2, Quad G.703 E1, ASI, LVDS, HSSI, 4-port 10/100Base-T Ethernet
  • IEEE 1588v2 Precision Time Protocol
  • Sub Mux to multiplex IP/Ethernet traffic with serial or G.703 traffic
  • Drop & insert for T1/E1
  • Enhanced D&I++ for single T1/E1 & quad E1
  • Management: 10/100Base-T Ethernet with SNMP, Distant End SNMP Proxy, HTTP, Telnet and EIA-232/EIA-485
  • Carrier ID using MetaCarrier® Technology
  • Embedded Distant-end Monitor and Control (EDMAC)
  • Automatic Uplink Power Control (AUPC)
  • Engineering Service Channel (ESC/ESC++)
  • Standard high-stability internal reference (± 6 x 10-8)
  • 5-tap Adaptive Equalizer
  • L-Band TX: 10 MHz reference for BUC, FSK communications and optional BUC power supply
  • L-Band RX: 10 MHz reference and LNB power supply
  • L-Band: Advanced FSK for LPOD M&C
  • 1:1 and 1:10 redundancy switches available
  • Backwards compatible with CDM-625

CDM-625A Specifications
Data Rate 18 kbps to 25 Mbps, in 1 bps steps (modulation, FEC & data interface dependant)
Symbol Rate 18 ksps to 12.5 Msps
Operating Frequency 50 – 180 MHz (standard) and 950 – 2250 MHz (option) 100 Hz resolution, independent TX and RX operation
Major Operating Modes
(See User Manual For Details)
Open network, per IESS-308 / 309 / 310 / 314 transparent, closed network per IESS-315
LDPC / TPC Codec (option)
VersaFEC Codec (option) with ACM or Constant Coding & Modulation (CCM) EDMAC Framed with/without AUPC
RS Outer Codec
High rate ESC / Enhanced ESC (ESC++)
Drop & insert (D&I) /Enhanced D&I++ (option)
Quad E1 drop & insert (QDI) (option)
DoubleTalk Carrier-in-Carrier (option)
FEC & Modulation
None Uncoded BPSK/QPSK/OQPSK
Viterbi: k=7, per IESS-308/309 Rate 1/2 BPSK/QPSK/OQPSK
Rate 3/4 QPSK/OQPSK
Rate 7/8 QPSK/OQPSK
Viterbi with Reed Solomon Rate 3/4 16-QAM
Rate 7/8 16-QAM
Sequential See CDM-625A user manual for details
Reed Solomon Open network and closed network modes
TCM (Per IESS-310) 8PSK/TCM Rate 2/3
Integrated LDPC and TPC (2nd Gen) Codec (Optional Plug-in Module) LDPC Code Rates
Rate 1/2 BPSK/QPSK/OQPSK
Rate 2/3 QPSK/OQPSK/8PSK/8-QAM
Rate 3/4 QPSK/OQPSK/8PSK/8-QAM/16-QAM
TPC Code Rates
Rate 5/16 BPSK
Rate 21/44 BPSK/QPSK/OQPSK
Rate 3/4 QPSK/OQPSK/8PSK/8-QAM/16-QAM
Rate 7/8 QPSK/OQPSK/8PSK/8-QAM/16-QAM
Rate 0.95 QPSK/OQPSK/8PSK/8-QAM
VersaFEC Codec (Option) BPSK Rate 0.488
QPSK Rate 0.533, 0.631, 0.706, 0.803
8-QAM Rate 0.576 (ECCM), 0.642, 0.711, 0.780
16-QAM Rate 0.644 (ECCM), 0.731, 0.780, 0.829, 0.853
BPSK 0.493 (ULL)
QPSK 0.493, 0.654, 0.734 (ULL)
VersaFEC-2 Codec (Option) Long Block:
BPSK Rate 0.489
QPSK Rate 0.489, 0.537, 0.586, 0.611, 0.635, 0.660, 0.684, 0.733
8-QARY Rate 0.521, 0.537, 0.562, 0.586, 0.611, 0.635, 0.660, 0.684, 0.708, 0.733
16-QARY Rate 0.586, 0.611, 0.635, 0.660, 0.684, 0.708, 0.733, 0.757, 0.782
32-ARY Rate 0.660, 0.684, 0.708, 0.733, 0.757, 0.782, 0.801, 0.831, 0.855, 0.879

Short Block:
BPSK Rate 0.489
QPSK Rate 0.489, 0.537, 0.586, 0.611, 0.635, 0.660, 0.684, 0.733
8-QARY Rate 0.521, 0.537, 0.562, 0.586, 0.611, 0.635, 0.660, 0.684, 0.708, 0.733
16-QARY Rate 0.586, 0.611, 0.635, 0.660, 0.684, 0.708, 0.733, 0.757, 0.782
32-ARY Rate 0.660, 0.684, 0.708, 0.733, 0.757, 0.782, 0.801, 0.831,
Scrambling IDR Mode, no RS, - per ITU V.35 (Intelsat variant)
IBS mode, no RS - per IESS-309, externally frame synchronized
Transparent Closed Network mode, no RS or Turbo coding - per ITU V.35 (Intelsat variant)
EDMAC mode, no RS coding - externally frame synchronized - proprietary
Turbo Product Code/LDPC/VersaFEC modes - externally frame synchronized - proprietary
All RS modes - externally frame synchronized per IESS-308/309/310
Management 10/100Base-T Ethernet with SNMP, HTTP and Telnet support, EIA-232, EIA-485 (2- or 4-wire)
Form C Relays Hardware fault, RX and TX traffic alarms, open network backward alarms
External Reference
(Input OR Output)
BNC connector
Input: 1, 2, 5, or 10 MHz, -6 dBm to +10 dBm, 50 Ω/75 Ω (nominal)
Output: 10 MHz, 2.7 V peak-to-peak ± 0.4 V, low impedance output
Data Interfaces
EIA-422/-530 DCE , Up to 14 Mbps 25-pin D-sub (female)
V.35 DCE , Up to 14 Mbps 25-pin D-sub (female)
LVDS Serial , Up to 25 Mbps 25-pin D-sub (female)
HSSI Serial , Up to 25 Mbps 25-pin D-sub (female)
G.703 T1, 1.544 Mbps (Balanced 100 Ω) 9-pin D-sub (female) or BNC (female)
G.703 T2, 6.312 Mbps (Unbalanced 75 Ω or balanced 110 Ω) 9-pin D-sub (female) or BNC (female)
G.703 E1, 2.048 Mbps (Unbalanced 75 Ω or balanced 120 Ω) 9-pin D-sub (female) or BNC (female)
G.703 E2, 8.448 Mbps (Unbalanced 75 Ω) 9-pin D-sub (female) or BNC (female)
ASI , Up to 25 Mbps BNC (female)
Additional 2.048 Mbps E1 Ports for Quad-E1 (Balanced 120 Ω) 9-pin D-sub (female)
Overhead Data 44-pin High-density D-sub (male)
Modem Alarms 15-pin D-sub (male)
4-port 10/100Base-T Managed Ethernet Switch
(Optional Packet Processor Available)
4 x RJ-45
Modulator
Frequency Stability ± 0.06 ppm (± 6 x 10-8), 0° to 50°C (32° to 122°F) with internal reference
Transmit Filtering Per IESS-308
Alpha (Rolloff) 5%, 10%, 15%, 20%, 25%, 35%
Harmonics and Spurious Better than -60 dBc/4 kHz (typically <-65 dBc/4kHz)
Measured from 1 to 500 MHz (50-180 MHz band)
Measured F0 ± 500 MHz (950-2250 MHz band)
Transmit On/Off Ratio -60 dBc minimum
Output Phase Noise (dB/Hz - Freq. Offset)
< 0.480° rms double sided, 100 Hz to 1 MHz
(Minimum 16 dB better overall than the Intelsat 
IESS-308/309 requirements)
-63.0 dB/Hz - 100 Hz
-73.0 dB/Hz - 1 kHz
-83.0 dB/Hz - 10 kHz
-93.0 dB/Hz - 100 kHz
Fundamental AC line spurious is -42 dBc or lower The sum of all other single sideband spurious, from 0 to 0.75 x symbol rate, is -48 dBc or lower
Output Power 50-180 MHz: 0 to -25 dBm, 0.1 dB steps
950-2250 MHz: 0 to -40 dBm, 0.1 dB steps
Power Accuracy 50-180 MHz: 
± 0.5 dB over frequency, data rate, modulation type and temperature range of 15 to 35° C 
± 0.8 dB over frequency, data rate, modulation type and temperature range of 0 to 50° C
950-2250 MHz:
± 0.7 dB over frequency, data rate, modulation type and temperature range of 15 to 35° C
± 1.0 dB over frequency, data rate, modulation type and temperature range of 0 to 50° C
Output Impedance & Return Loss 50-180 MHz: 50 Ω/75 Ω, 16 dB minimum return loss (18 dB typical), BNC connector
950-2250 MHz: 50 Ω, 19 dB minimum return loss (21 dB typical), Type-N connector
Clocking Options Internal, ± 0.06 ppm (SCT)
External, locking over a ± 100 ppm range (TT)
Loop timing (RX satellite clock) – supports asymmetric operation
External clock
External TX Carrier Off By TTL ‘low’ signal or external contact closure
BUC Reference (10 MHz) Via TX IF center conductor, 10.0 MHz ± 0.06 ppm (with internal reference), selectable on/off, 0.0 dBm ± 3 dB
BUC Power Supply (HW Option) 24 VDC, 4.17 Amps max., 90 W @ 50° C 48 VDC, 3.125 Amps max., 150 W @ 50° C (180 W @ 30° C)
Supplied through TX IF center conductor and selectable on/off via M&C control
Demodulator
Input Power Range, Desired Carrier 50-180 MHz: -105 + 10 log (symbol rate) to -70 + 10 log (symbol rate) dBm
950-2250 MHz: -130 + 10 log (symbol rate) to -80 + 10 log (symbol rate) dBm
Max Composite Operating Level 50-180 MHz: 94 – 10 log (symbol rate, desired carrier) dBc, +10 dBm max., with the additional requirement that within ± 10 MHz of the desired carrier the composite power is ≤ +30 dBc
950-2250 MHz: 102 – 10 log (symbol rate, desired carrier) dBc, +10 dBm max., with the additional requirement that within ± 10 MHz of the desired carrier the composite power is ≤ +30 dBc
Absolute Maximum +20 dBm
Adaptive Equalizer 5-tap design, selectable on/off
Acquisition Range Programmable in 1kHz increments
Below 64 ksymbols/sec ± 1 kHz to ± (Rs/2) kHz, where Rs = symbol rate in ksymbols/sec
Between 64 and 389 ksymbols/sec ± 1 kHz to ± 32 kHz
Above 389 ksymbols/sec ± 1 kHz to ± (0.1 * Rs) kHz, up to a maximum of ± 200 kHz
Acquisition Time Highly dependent on data rate, FEC rate, and demodulator acquisition range. E.g. 120 ms average at 64 kbps, R1/2 QPSK, ± 10 kHz acquisition sweep range, 6 dB Eb/No
Plesiochronous/ Doppler Buffer Selectable from 64 to 262,144 bits, in 16-bit steps (Additional limitations for G.704 frame boundaries)
Receive Clock RX satellite, TX terrestrial, external reference
Clock Tracking ± 100 ppm minimum
LNB Reference (10 MHz) Via RX IF center conductor, 10.0 MHz ± 0.06 ppm (with internal reference), selectable on/off, -3.0 dBm ± 3 dB
LNB Voltage Selectable on/off, 13 VDC, 18 VDC per DiSEq 4.2 and 24 VDC at 500 mA maximum
Monitor Functions Eb/N0 estimate, corrected BER, frequency offset, buffer fill state, receive signal level
DoubleTalk Carrier-in-Carrier
Delay Range 0 to 330 ms
Power Spectral Density Ratio
(Interferer to Desired)
BSPK/QPSK/8PSK/8-QAM: –7 dB to +11 dB
16-QAM: -7 dB to +7 dB
Maximum Symbol Rate Ratio 3:1 (TX:RX or RX:TX)
Eb/No Degradation 0 dB Power Spectral Density Ratio
BPSK/QPSK/OQPSK: 0.3 dB
8-QAM: 0.4 dB
8PSK: 0.5 dB
8-ARY: 0.4 dB
16-QAM: 0.6 dB
16-ARY: 0.6 dB
32-ARY: 0.6 dB
+10 dB power spectral density ratio
Additional 0.3 dB
Satellite Restrictions Satellite in “loop-back” mode (i.e., the transmit station can receive itself)
“Non-processing” satellite (i.e., does not demodulate or remodulate the signal)
Environmental and Physical
Temperature Operating: 0 to 50°C (32 to 122°F)
Storage: -25 to 85°C (-13 to 185°F)
Power Supply 100 – 240 VAC, +6%/-10%, 50/60 Hz, auto sensing
-24 VDC (HW option) -48 VDC (HW option)
Dimensions (1RU) (height x width x depth) 1.75” x 19.0” x 17.65” (4.4 x 48 x 44.8 cm) approximate
Weight 10.8 lbs (4.9 kg) maximum, with all option modules and 48 VDC BUC power supply installed
CE Mark EN 301 489-1 (ERM)
EN55022 (Emissions) 
EN55024 (Immunity)
EN 61000‐3‐2
EN 61000‐3‐3 
EN60950 (Safety)
FCC FCC Part 15, Subpart B
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