Wireless Facts; The Link Budget Tool - Alvarion BreezeACCESS LB System Manual

Wireless Facts

Wireless technology has existed for many years, proving it to be a
reliable communication medium, primarily for long haul point-to-point
applications supporting critical links across the country for telephony
and broadcast services. With the surge of broadband two-way internet
use, fixed wireless systems are playing an even more important role in
supporting network infrastructures.
The BreezeACCESS LB NI-01 Indoor unit has been designed to operate
in the band, which occupies the license exempt portion of the
spectrum. This allows an operator to set up a wireless network without
requiring formal consent from the regulatory agent. While this provides
great advantages in terms of cost and time to market, the ease of access
to the spectrum can bring with it undesirable effects, such as potential
interference arising from other users exploiting the "free" band. By
following the simple deployment guidelines in this manual, issues of
this nature can be avoided.
This section includes a description of the Link Budget tool, Fresnel zone
considerations, height calculations and radar horizon issues,
interference issues with other systems, etc.

The Link Budget Tool

Alvarion has available a Link Budget Tool to help characterize the range
performance of the BreezeACCESS LB NI-01 Indoor unit for LOS (line of
sight), OLOS (optical line of sight) and NLOS conditions, including
various system parameters. The Link Budget Tool can be obtained by
contacting your Alvarion 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. In addition, 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 10E-9, for
an availability of 99.99%. Availability is described in more detail below.
Wireless Facts
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