Comtech EF Data CDM-625A Installation And Operation Manual page 55

CDM-625A Advanced Satellite Modem
Introduction
VersaFEC CODEC BER
8-QAM
(With two adjacent carriers,
each 7 dB higher than the
desired carrier)
VersaFEC CODEC BER
16-QAM
(With two adjacent carriers,
each 7 dB higher than the
desired carrier)
VersaFEC CODEC - Extended
CCM BER
(With two adjacent carriers,
each 7 dB higher than the
desired carrier)
Ultra-Low-Latency (ULL)
CODEC BER
(With two adjacent carriers,
each 7 dB higher than the
desired carrier)
Plesiochronous/
Doppler Buffer
Monitor Functions
Notes:
1) Rate 21/44 QPSK is shown as Rate 1/2 on the Front Panel display, etc.
2) The demod acquisition and tracking threshold for OQPSK is approx 1 dB worse than the QPSK case in this mode.
Rate 0.642 8-QAM
Guaranteed Eb/No:
(typical value in
parentheses)
For:
BER=10 4.6 dB (4.3 dB)
-5
BER=10 4.9 dB (4.6 dB)
-8
R 0.731 16-QAM
Guaranteed Eb/No:
(typical value in
parentheses)
For:
BER=10 6.6 dB (6.3 dB)
-5
BER=10 6.8 dB (6.5 dB)
-8
R 0.576 8-QAM
Guaranteed Eb/No:
(typical value in
parentheses)
For:
BER=10 4.5 dB (4.2 dB)
-5
BER=10 4.9 dB (4.6 dB)
-8
R 0.493 BPSK
Guaranteed Eb/No:
(typical value in
parentheses)
For:
BER=10 3.1 dB (2.8 dB)
-5
BER=10 3.7 dB (3.4 dB)
-8
Selectable size of 64 to 262,144 bits, in 16-bit steps (with added limitations for G.704 frame boundaries).
Size selection is displayed in bytes and milliseconds.
Supports asymmetric operation - when buffer is clocked from Tx clock, Rx and Tx rates do not need to be identical.
Eb/No estimate:
2 to 10 dB with ± 0.3 dB accuracy
0 to 16 dB with ± 0.5 dB accuracy
Corrected Bit Error Rate, 1E-3 to 1E-10
Frequency offset, ± 32 kHz range, (or 200 kHz range, depending on band and symbol rate) 100 Hz resolution
Buffer fill state, in percent
Receive signal level:
950-2250 MHz band accuracy: ± 3 dB
50-180 MHz band accuracy: ± 2 dB
Rate 0.711 8-QAM
Guaranteed Eb/No: Guaranteed Eb/No:
(typical value in
parentheses)
5.2 dB (4.9 dB)
5.5 dB (5.2 dB)
R 0.780 16-QAM
Guaranteed Eb/No: Guaranteed Eb/No:
(typical value in
parentheses)
7.1 dB (6.8 dB)
7.4 dB (7.1 dB)
R 0.644 16-QAM
Guaranteed Eb/No:
(typical value in
parentheses)
6.4 dB (6.1 dB)
6.9 dB (6.6 dB)
R 0.493 QPSK
Guaranteed Eb/No:
(typical value in
parentheses)
3.1 dB (2.8 dB)
3.7 dB (3.4 dB)
1–19
Revision 0
MN-CDM625A
Rate 0.780 8-QAM
(typical value in
parentheses)
5.6 dB (5.3 dB)
6.0 dB (5.7 dB)
R 0.829 16-QAM R 0.853 16-QAM
Guaranteed Eb/No:
(typical value in (typical value in
parentheses) parentheses)
7.7 dB (7.4 dB) 8.1 dB (7.8 dB)
8.0 dB (7.7 dB) 8.4 dB (8.1 dB)
R 0.654 QPSK R 0.734 QPSK
Guaranteed Eb/No: Guaranteed Eb/No:
(typical value in (typical value in
parentheses) parentheses)
3.6 dB (3.3 dB) 4.1 dB (3.8 dB)
4.2 dB (3.9 dB) 4.7 dB (4.4 dB)