Comtech EF Data CDM-570 - Page 54

CDM-570/570L Satellite Modem with Optional IP Module Revision 12
Introduction MN/CDM570L.IOM
1–14
IMPORTANT NOTE: Starting with Release 1.4.1 of the CDM-570/570L firmware, the maximum symbol
rate has been increased from 2.5 to 3.0 Msymbols/sec. This has been done without modification to
the hardware, and as a consequence, there may be a small degradation in BER versus E
b
/N
0
performance for rates above 2.5 Msymbols/sec. The degradation is as follows:
Rates from 2.5 to 2.65 Msps: degradation < 0.1 dB
Rates from 2.65 to 2.80 Msps: degradation < 0.2 dB
Rates from 2.80 to 3.00 Msps: degradation < 0.3 dB
VITERBI
BER performance
(met in the presence of two
adjacent carriers, each 7 dB
higher than the desired
carrier)
For:
BER=10
-5
BER=10
-6
BER=10
-7
Rate 1/2 (B, Q, OQ)
Guaranteed Eb/No:
(typical value in parentheses)
5.4 dB (4.9 dB)
6.0 dB (5.5 dB)
6.7 dB (6.2 dB)
Rate 3/4 (Q, OQ)
Guaranteed Eb/No:
(typical value in
parentheses)
6.8 dB (6.3 dB)
7.4 dB (6.9 dB)
8.2 dB (7.7 dB)
Rate 7/8 (Q, OQ)
Guaranteed Eb/No:
(typical value in
parentheses)
7.7 dB (7.2 dB)
8.4 dB (7.9 dB)
9.0 dB (8.6 dB)
VITERBI and R-S 220,200
or 200,180 Outer Code
BER
(with two adjacent carriers,
each 7 dB higher than the
desired carrier)
For:
BER=10
-5
BER=10
-6
BER=10
-7
Rate 1/2 (B, Q, OQ)
Guaranteed Eb/No:
(typical value in parentheses)
4.3 dB (4.0 dB)
4.4 dB (4.1 dB)
4.5 dB (4.2 dB)
Rate 3/4 (Q, OQ)
Guaranteed Eb/No:
(typical value in
parentheses)
5.6 dB (4.7 dB)
5.8 dB (4.8 dB)
6.0 dB (5.2 dB)
Rate 7/8 (Q, OQ)
Guaranteed Eb/No:
(typical value in parentheses
)
6.5 dB (6.0 dB)
6.7 dB (6.2 dB)
6.9 dB (6.5 dB)
8-PSK/TCM
/
R-S CODEC
BER
(With two adjacent
carriers, each 7 dB higher
than the desired carrier)
For:
BER=10
-5
BER=10
-7
BER=10
-8
R 2/3 8-PSK/TCM
/
R-S
Guaranteed Eb/No:
(typical value in
parentheses)
6.3 dB (5.4 dB)
6.7 dB (5.8 dB)
6.9 dB (6.0 dB)
TURBO PRODUCT CODEC
Rate 21/44 QPSK
Rate 21/44 BPSK
Rate 5/16 BPSK
BER
(With two adjacent carriers,
each 7 dB higher than the
desired carrier)
For:
BER=10
-6
BER=10
-7
BER=10
-8
Rate 21/44
(Q, OQ)
Guaranteed Eb/No:
(typical value in parentheses)
2.9 dB (2.6 dB)
3.1 dB (2.7 dB)
3.3 dB (2.8 dB)
Rate 21/44 (B)
Guaranteed Eb/No:
(typical value in
parentheses)
2.8 dB (2.5dB)
3.1 dB (2.8 dB)
3.3 dB (2.90dB)
Rate 5/16 (B)
Guaranteed Eb/No:
(typical value in parentheses
)
2.4 dB (2.1dB)
2.6 dB (2.3dB)
2.7 dB (2.4dB)
TURBO PRODUCT CODEC
Rate 3/4 QPSK
Rate 3/4 8-PSK
Rate 3/4 16-QAM
BER
(With two adjacent carriers,
each 7 dB higher than the
desired carrier)
For:
BER=10
-6
BER=10
-7
BER=10
-8
Rate 3/4 (Q, OQ)
Guaranteed Eb/No:
(typical value in parentheses)
3.8dB (3.4dB)
4.1dB (3.7dB)
4.4dB (4.0dB)
Rate 3/4 (8-PSK)
Guaranteed Eb/No:
(typical value in
parentheses)
6.2 dB (5.8 dB)
6.4 dB (6.0 dB)
6.8 dB (6.3 dB)
Rate 3/4 (16-QAM)
Guaranteed Eb/No:
(typical value in parentheses
)
7.4dB (7.0 dB)
7.8 dB (7.3 dB)
8.2 dB (7.7 dB)