Comtech EF Data CDD-880, Installation And Operation Manual

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CDD-880 Multi Receiver
Router
MN-CDD880
Appendix H Revision 2
H–13
H.7 Summary of Specifications
System Type
Adaptive Coding and Modulation, using BPSK, QPSK, 8-QAM , 16-QAM and
VersaFEC short-block LDPC coding – total of 12 MODCODs (00 through 11)
Symbol Rate Range 16 ksps to 4500 ksps
Interface 10/100 BaseT Ethernet, with auto-negotiated Congestion Control
Remote Es/No Teporting
Automatically reported by the CDD-880 and sent to the CDM-840 Management IP
Interface.
Max Span of Data Rate 7:1 over range of adaptation
Switch Point (Decreasing SNR) Corresponds to SNR (Es/No) that gives BER = 5 x 10
-8
(margin set to 0 dB)
Switch Point Hysteresis 0.3 dB
Max Fading Rate Approximately 1 dB/second (higher if Target Eb/No margin > 1 dB)
Max MODCOD Update Rate
One update every 0.5 seconds during fast fade conditions, and every 30 seconds
when the measured Es/No is stable.
Configurable Parameters
• Maximum MODCOD (MODCOD 00 through MODCOD 11)
•
Target Es/No margin (0.0 to 4.5 dB, 0.5 dB steps)
System Latency 34 milliseconds max (not including WAN buffer, or satellite path)
Monitored Parameters
•
Tx and Rx MODCODs
•
CDD-880 Es/No
(-3.0 dB to +22.0dB, 0.1dB resolution, ±0.5 dB accuracy)
• Config and monitor menus displaying data rate, modulation and code rate update
dynamically with MODCOD
Modulation
(MODCOD No.)
Code Rate
Spectral
Efficiency, bps/Hz
Typical Eb/No, for
BER = 5 x 10
-8
(dB)
Data Rate, ACM Mode
Minimum (kbps) Maximum (Mbps)
BPSK (00) 0.488 0.49 2.4 16 2.2
QPSK (01) 0.533 1.07 2.2 17 4.81
QPSK (02) 0.631 1.26 2.7 20 5.67
QPSK (03) 0.706 1.41 3.4 22 6.34
QPSK (04) 0.803 1.61 3.8 25 7.24
8-QAM (05) 0.642 1.93 4.6 30 8.68
8-QAM (06) 0.711 2.13 5.2 34 9.58
8-QAM (07) 0.780 2.34 5.6 37 10.53
16-QAM (08) 0.731 2.93 6.5 46 13.18
16-QAM (09) 0.780 3.12 7.1 49 14.04
16-QAM (10) 0.829 3.32 7.7 53 14.94
16-QAM (11) 0.853 3.41 8.1 54 15.34