Redline Communications AN-50, Руководство пользователя

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AN-50 System User Manual
Redline Communications …..solving the first mile challenge .
This section provides additional background material to section 7 of this manual,
including a description of the Link Budget tool, Fresnel zone considerations, height
calculations and radar horizon issues, interference issues with other systems, etc.
9.7.1. The Link Budget Tool
Redline has developed a Link Budget Tool to help characterize the range performance
of the AN-50 system for LOS, OLOS (optical line of sight) and NLOS conditions and
various system parameters. The Link Budget Tool can be obtained by contacting your
Redline certified partner or system integrator. Note the tool provides a first-order
approximation, and does not consider the details of any specific terrain profile which may
impact performance; rather, a generalized terrain is used in the calculations, based on
empirical formulas approved by governing bodies such as the IEEE and ITU. Also, the
tool does not consider system parameter variations arising from temperature
fluctuations, cable loss tolerance, antenna alignment errors, etc.
The Link Budget Tool estimates the distance over which the system can operate at a
desired error rate while achieving robust communication. A link is considered robust if
the average error rate is less than 1 bit out of every 1000 million, expressed as 10
-9
, for
an availability of 99.99%. Availability is described in more detail below.
The table below describes the net data rate (after coding overhead) that can be obtained
for each modulation type in an ideal propagation situation.
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