Comtech EF Data cdm-570a - Page 56

CDM-570A/570AL Satellite Modem with Optional Packet Processor
Revision 5
Introduction 1–16 MN-CDM570A
Parameter
Specification
FEC (cont.)
• VersaFEC-2
®
Short-Block Codec (Optional plug-in card – low latency LDPC):
o Rate 0.489 BPSK
o Rate 0.489, 0.537, 0.586, 0.611, 0.635, 0.660, 0.684, 0.733 QPSK
o Rate 0.521, 0.537, 0.562, 0.586, 0.611, 0.635, 0.660, 0.684, 0.708, 0.733 8-ARY
o Rate 0.586, 0.611, 0.635, 0.660, 0.684, 0.708, 0.733, 0.757, 0.782 16-ARY
o Rate 0.660, 0.684, 0.708, 0.733, 0.757, 0.782, 0.801, 0.831 32-ARY
Harmonics and Spurious
-60 dBC/4 kHz from 600 to 2600 MHz (L-Band) and from 1 to 400 MHz (IF)
Transmit Filtering
Per Intelsat IESS-308 (FIR digital filter implementation)
Root-Raised Cosine, alpha = 0.05, 0.10, 0.15, 0.20, 0.25, and 0.35 roll-off
Transmit On/Off Ratio
55 dB minimum
Scrambling
• Transparent, Closed Network mode, no R-S or Turbo coding - per ITU V.35 (Intelsat variant)
• EDMAC mode, no R-S coding - externally frame synchronized - proprietary
• Turbo Product Code mode - externally frame synchronized - proprietary
• All R-S modes - externally frame synchronized per IESS-308/309/310
• All VersaFEC and VersaFEC-2 modes use IESS-315/V.35
Clocking Options
• Internal – CDM-570AL or CDMR-570AL (L-Band)±0.06 ppm (SCT);
CDM-570A (70/140 MHz) ±1.0 ppm (SCT)
• External – Locking over a ±100 ppm range (TT)
• Loop timing (Rx satellite clock) – Supports asymmetric operation; Rx and Tx data rates do not need to be
identical
External TX Carrier Off
By TTL 'low' signal or external contact closure – hardware function automatically over-rides processor, or by
RTS signal on main data interface
Output Impedance
CDM-570AL or CDMR-570AL (L-Band): 50Ω, >17 dB from 950 to 2250 MHz and >19 dB from 1000 to 1900
MHz minimum return loss
CDM-570A (70/140 MHz): Compatible with 50Ω or 75Ω,17 dB minimum return loss
Output Connector
CDM-570AL or CDMR-570AL (L-Band):Type ‘N’ female
CDM-570A (70/140 MHz): BNC female
Output Frequency
CDM-570AL or CDMR-570AL (L-Band): 950 to 2250 MHz, 100 Hz resolution
Stability ±0.06 ppm (±6 x 10
-8
) 0 to 50°C (32 to 122°F), when using internal reference
CDM-570A (70/140 MHz): 50 to 90 MHz, and 100 to 180 MHz, 100 Hz resolution
Stability ±1.0 ppm (±1 x 10
-6
) 0 to 50°C (32 to 122°F), when using internal reference
Output Phase Noise
CDM-570AL or CDMR-570AL (L-Band): <1.2° RMS double-sided, 100 Hz to 1 MHz for CDM-570AL and
CDM-570AL-IP
CDM-570A (70/140 MHz): <0.75° RMS double-sided, 100 Hz to 1 MHz for CDM-570A and CDM-570A-IP
Output Power
CDM-570AL or CDMR-570AL (L-Band):0 to -40 dBm, 0.1 dB steps - manual mode. Also – see Sect. 1.2.6
for Automatic Uplink Power Control.
CDM-570A (70/140 MHz): 0 to -25 dBm, 0.1 dB steps - manual mode. Also – see Sect. 1.2.6 for Automatic
Uplink Power Control.
Power Accuracy
CDM-570AL or CDMR-570AL (L-Band): ±1.0 dB over frequency, data rate, modulation type and
temperature
CDM-570A (70/140 MHz): ±0.5 dB over frequency, data rate, modulation type and temperature
BUC Reference
(10 MHz)
CDM-570AL or CDMR-570AL: On center conductor of L-Band output connector; 10.0 MHz ± 0.06 ppm*
(Optional 1 ppm)
-1.0 dBm, ± 4 dBm; programmable ON/OFF
*Source: Selected as Internal.
Phase Noise
dB/Hz
-110
-135
-140
Frequency Offset
10 Hz
100 Hz
1 kHz