Comtech EF Data Vipersat SLM-5650A, Инструкция по установке и эксплуатации

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SLM-5650A Satellite Modem
Revision 10
Specifications 2–10 MN-SLM-5650A
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"
s
) = 2.0 R'
s
, the modem
performance is not degraded more than indicated in Table 2-17 Column 4, and a) and b) in this
section. Performance is measured with the adjacent carriers center frequencies offset (X/2) times
(R'
s
+ R"
s
) Hz from the test carrier center frequency, where X is the spacing factor and R'
s
is the
modulation symbol rate in Hz of the test carrier, and R"
s
is the modulation symbol rate in Hz of
each adjacent carrier. For modulation symbol rates below 38.4 ksps, this paragraph does not
apply.
For X (spacing factor) = 1.2, and R"
s
= 2.0 R'
s
, the asymmetric degradation shall be IAW one of
the values in Table 2-17 Column 4, and the corresponding test carrier E
s
/N
0
in Column 1. Select a
test carrier E
s
/N
0
that will yield timely results based on modulation and coding used in the test
configuration. The adjacent carriers E
s
/N
0
are set to the corresponding value in Column 2.
For the case of (1.4/2)(R'
s
+ R"
s
) Hz carrier spacing, the degradation is < 0.2 dB.
Table 2-17. Acceptable ACI Degradation with Spacing Factor of 1.2
Test Carrier
E
s
/N
0
(dB)
Adjacent Carriers
E
s
/N
0
(dB)
E
b
/N
0
Degradation (dB)
Symmetric Case
E
b
/N
0
Degradation (dB)
Asymmetric Case
5.5 18.5 < 0.36 < 0.41
6.0 19.0 < 0.38 < 0.43
8.0 21.0 < 0.48 < 0.56
8.4 21.4 < 0.51 < 0.60
10.0 23.0 < 0.64 < 0.77
12.0 25.0 < 0.88 < 1.10
12.7 25.7 < 0.99 < 1.21