As a result of calculation, the maximum radius for signal coverage has QPSK
í µí±™
í µí±„í µí±ƒí µí±†í µí°¾
=1,53 km, QAM-16 – í µí±™
í µí±„í µí°´í µí±€âˆ’16
=0,91 km, QAM-64 – í µí±™
í µí±„í µí°´í µí±€âˆ’64
=0,54 km,
QAM-256 –
í µí±™
í µí±„í µí°´í µí±€âˆ’256
=0,3 km (Fig. 6).
The radius of modulations coverage with different antinoise coding rates namely
1/2, 3/5, 2/3, 3/4, 4/5, 5/6 versus SNR, constructed are partially shown on Fig. 7. In
total, 24 gradations combination of modulation and coding types estimated in the form
of rings with base station in its center.
Figure 6. The dependence of BER for various modulation types
to signal propagation range
Source: developed by the author
Calculated total system throughput taking into account all modulation types
amounted
í µí±…
σ
=2,6â‹…10
9
í µí±…
σ
=2,6â‹…10
9
bit/s for 596 subscribers.
Figure 7. The dependency of modulated signals propagation distances from
coding gradations
Source: developed by the author
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