Ber Performance With Asymmetrical Adjacent Carriers; Ldpc Ull Decoding; Table 1-19. Ldpc Ull Decoder Ber Performance - Comtech EF Data SLM-5650B Installation And Operation Manual

1.4.1.3.9

BER Performance with Asymmetrical Adjacent Carriers

Operating in the presence of two adjacent asymmetrical carriers, one lower in frequency and one
higher in frequency, and each adjacent carrier symbol rate (R"
is not degraded more than indicated in Table 1-18 Column 4, and a) and b) in this section.
Performance is measured with the adjacent carriers center frequencies offset (X/2) times (R'
Hz from the test carrier center frequency, where X is the spacing factor and R'
symbol rate in Hz of the test carrier, and R"
carrier. For modulation symbol rates below 38.4 ksps, this paragraph does not apply.
a) For X (spacing factor) = 1.2, and R"
one of the values in Table 1-18 Column 4, and the corresponding test carrier E
Column 1. Select a test carrier E
and coding used in the test configuration. The adjacent carriers E
corresponding value in Column 2.
b) For the case of (1.4/2)(R'
Table 1-18. Acceptable ACI Degradation with Spacing Factor of 1.2
Test Carrier
E /N (dB)
s 0
5.5
6.0
8.0
8.4
10.0
12.0
12.7
1.4.1.3.10

LDPC ULL Decoding

BER
-5
10
10
-8
Introduction
is the modulation symbol rate in Hz of each adjacent
s
= 2.0 R'
s
/N that will yield timely results based on modulation
s 0
+ R" ) Hz carrier spacing, the degradation is < 0.2 dB.
s s
Adjacent Carriers E
E /N (dB)
s 0
18.5
19.0
21.0
21.4
23.0
25.0
25.7

Table 1-19. LDPC ULL Decoder BER Performance

E b /N 0 (dB) Specification
BPSK
1/2
3.1
3.7
1–25
) = 2.0 R'
s
, the asymmetric degradation shall be IAW
s
/N Degradation (dB)
b 0
Symmetric Case
< 0.36
< 0.38
< 0.48
< 0.51
< 0.64
< 0.88
< 0.99
QPSK
1/2 2/3
3.1 3.6
3.7 4.2
SLM-5650B Satellite Modem
Revision 2
, the modem performance
s
+ R"
s
is the modulation
s
/N in
s 0
/N are set to the
s 0
E /N Degradation (dB)
b 0
Asymmetric Case
< 0.41
< 0.43
< 0.56
< 0.60
< 0.77
< 1.10
< 1.21
3/4
4.1
4.7
MN-SLM-5650B
)
s