Ceragon FA4800, Руководство пользователя

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Calculations Chapter 21
FA4800 User Manual Release 1.9.30 21-2
• Antenna gain and cable loss for ODU with integrated antenna
• Available Channel Bandwidths
Calculations
EIRP
Expected RSS and Fade Margin
where:
Site A is the transmitting site
Site B is the receiving site
PathLoss is calculated according to the free space model,
where Sensitivity is dependent on air-rate.
Min and Max Range
MinRange is the shortest range for which
per air-rate.
MaxRange (with Adaptive checked) is the largest range for which
, at the highest air-rate for which this relation-
ship is true. In a link with adaptive rate this will be the actual behavior.
MaxRange (for a given air-rate) is the largest range for which
.
Service
The Ethernet and configured TDM trunks throughput is calculated according
to internal product algorithms.
Availability
The Service Availability calculation is based on the Vigants Barnett method
which predicts the downtime probability based on a climate factor (C fac-
tor).
EIRP TxPower AntennaGain
SiteA
CableLoss
SiteA
– + =
ExpectedRSS EIRP PathLoss AntennaGain
SiteB
CableLoss
SiteB
– + – =
PathLoss 32.45 20 frequency
MHz
( )
20 RequiredRange
Km
( )
10
log
×
+
10
log
×
+ =
ExpectedFadeM in arg ExpectedRSS Sensitivity – =
ExpectedRSS MaxInputPower
≤
ExpectedRSS Sensitivity
≥
ExpectedRSS Sensitivity RequiredFadeM in arg +
≥