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Comtech EF Data

Comtech EF Data CDM-625A Advanced Satellite Modem

Comtech EF Data CDM-625A Advanced Satellite Modem

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SKU: CDM-625A

COMTECH CDM-625A ADVANCED SATELLITE MODEM

    CDM-625A 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

      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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