P300H P300 Series Modem Installation and Operating Handbook Page 164
8.12.5 Tables to Convert (C+N)/N to Eb/No
N
N
+
C
N
E
=
N
C
0
S
N
E
0
t
N
E
0
Dec
N
E
0
b
0
0
0
0
0
4.6
4.8
2.75
3.05
5.0
5.2
5.4
5.6
3.35
3.64
3.92
4.20
4.47
5.8
6.0
6.2
6.4
6.6
6.8
4.74
5.01
5.27
5.53
5.78
7.0
7.2
7.4
7.6
7.8
6.03
6.28
6.53
6.77
7.01
8.0
7.25
8.2
7.49
8.4
7.72
8.6
7.95
8.8
8.19
9.0
8.42
9.2
8.64
9.4
8.87
9.6
9.10
9.8
9.32
10.0
9.54
10.5
10.09
11.0
11.5
12.0
12.5
13.0
13.5
14.0
14.5
10.64
11.18
11.72
12.25
12.78
13.30
13.82
14.34
Adjust for
modulation:
BPSK: -0dB
QPSK: -3.0dB
OQPSK: -3.0dB
8PSK: -4.77dB
Adjust for
FEC Rate:
1/2 Rate: +3.0dB
3/4 Rate: +1.25dB
7/8 Rate: +0.58dB
2/3 Rate: +1.76dB
Adjust for
RS Codec:
(n,k,t)=
(126,112,7): +0.51dB
(219,201,9): +0.37dB
(225,205,10): +0.40dB
15.0
15.5
16.0
16.5
17.0
17.5
18.0
18.5
19.0
19.5
14.86
15.38
15.89
16.40
16.91
17.42
17.93
18.44
18.94
19.45
>20
=(C+N) / N
(error <0 .04dB)
Example:
8SPK with 2/3 Rate TCM FEC, & RS=(219,201,9)
