Alvarion BreezeACCESS VL 5.4 System Manual page 94

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lower is 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 the
Current Transmit Power, which is the last value that was previously used
by the ATPC mechanism. If after a certain configurable time the SU did
not succeed to synchronize with the AU, it will start transmitting using the
level configured for the Initial Transmit Power parameter. (If this is the
first time that the SU is powered up, or if the ATPC algorithm was not
used, the Current Transmit Power equals the value of Initial Transmit
Power).
The Initial Transmit Power parameter is used to determine the fixed
transmit power level of the SU if the ATPC algorithm is not enabled.
In an AU typically the maximum supported transmit power is used to
enable 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.
Transmit Power (AU)
The Transmit Power parameter defines the transmit power level of the AU.
This parameter is not part of the ATPC algorithm.
Valid range: 4 to 28 (dBm), using a 1 dBm resolution.
The default is 11 (dBm).
Initial Transmit Power (SU)
The Initial Transmit Power parameter defines the fixed transmit power level
when the ATPC algorithm is disabled. If the ATPC Option is enabled this
parameter serves for setting the initial value to be used by the ATPC
algorithm after the first time of powering-up the unit. It will also be used
by the algorithm as an initial value in the following cases:
a. If the unit does not succeed to associate with the AU after reset.
b. If the unit does not succeed to re-synchronize with the AU after losing
synchronization.
c. If the SU is associated with the AU but there are too many successive
dropped frames, indicating that it transmits at a level that may be too low.
The actual run-time value that is used to control the transmit power level
is determined by the ATPC process.
BreezeACCESS VL System Manual