Alvarion BreezeACCESS VL System Manual page 159

by a configurable parameter. In addition, the higher the time that has passed
since the last calculation, the lower the impact of history on the calculated
average. If the average SNR is not in the configured target range, the AU
transmits to the SU a power-up or a power-down message. The target is that each
SU will be received at an optimal level, or as high (or low) as possible if the
optimal range cannot be reached because of specific link conditions.
Each time that the SU tries to associate with the AU (following either a reset or
loss of synchronization), it will initiate transmissions using its Transmit Power
parameters. If after a certain time the SU does not succeed to synchronize with
the AU, it will start increasing the transmit power level.
In an AU the maximum supported transmit power is typically used to provide
maximum coverage. However, there may be a need to decrease the transmitted
power level in order to support relatively small cells and to minimize the
interference with the operation of neighboring cells, or for compliance with local
regulatory requirements.
In some cases the maximum transmit power of the SU should be limited to
ensure compliance with applicable regulations or for other reasons.
Different power levels may be used for different modulation levels by taking into
account possible HW limitations or regulatory restrictions.
4.2.6.2.8.1 Transmit Power
The Transmit Power submenu includes the following options:
Transmit Power
Show Transmit Power Parameters
4.2.6.2.8.1.1 Transmit Power
In the AU, the Transmit Power parameter defines the fixed transmit power level
and is not part of the ATPC algorithm.
In the SU, the Transmit Power parameter defines the fixed transmit power level
when the ATPC algorithm is disabled. If the ATPC Option is enabled, the value
configured for this parameter serves for setting the initial value to be used by the
ATPC algorithm after either power up or losing synchronization with the AU.
The minimum value for the Transmit Power Parameter is -10 dBm (the ATPC may
reduce the actual transmit power of the SU to lower values). The maximum value
of the Transmit Power Parameter depends on several unit properties and
parameters:
The HW revision of the unit
Operation and Administration
Menus and Parameters
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