Alvarion Technologies Ltd. BMAX-BA36 ユーザーズマニュアル
Base Station Menu
BreezeMAX Modular Base Station System Manual
103
AU-ODU at an optimal level. ATPC is required to minimize the interference caused
by a strong signal of an SU from one sector to other SU units in another sector.
The ATPC algorithm will cause the SU to transmit a power level that minimizes the
interference to other SU units, while maintaining a sufficient receiving power
level. The algorithm is managed by the AU and optimal values are calculated
separately for each SU based on the actual level at which it is received by the
AU-ODU. MAP messages transmitted to the SUs include information on the
estimated power level change required to achieve optimal transmit power level.
by a strong signal of an SU from one sector to other SU units in another sector.
The ATPC algorithm will cause the SU to transmit a power level that minimizes the
interference to other SU units, while maintaining a sufficient receiving power
level. The algorithm is managed by the AU and optimal values are calculated
separately for each SU based on the actual level at which it is received by the
AU-ODU. MAP messages transmitted to the SUs include information on the
estimated power level change required to achieve optimal transmit power level.
When several SUs transmit simultaneously each one increases the total level of
noise. If a “strong” SU transmits simultaneously with a very “weak” SU, the noise
induced by the “strong” one may cause the SNR of the “weak” SU to be too low. In
order to avoid this, all SUs should not be too “strong” – their RSSI at the AU-ODU
should be not be higher than a nominal RSSI (typically -74 dBm), defined by the
Optimal Rx RSSI parameter. Changing the amount of subchannels may cause
change in RSSI. In order to avoid this, reduction in amount of subchannels from
16 (full bandwidth) to 8, 4, 2 or 1, will be accompanied with a reduction of 3, 6, 9
or 12 dBm, respectively, in the SU’s Tx power (unless the RSSI of the SU is below
the nominal RSSI level).
noise. If a “strong” SU transmits simultaneously with a very “weak” SU, the noise
induced by the “strong” one may cause the SNR of the “weak” SU to be too low. In
order to avoid this, all SUs should not be too “strong” – their RSSI at the AU-ODU
should be not be higher than a nominal RSSI (typically -74 dBm), defined by the
Optimal Rx RSSI parameter. Changing the amount of subchannels may cause
change in RSSI. In order to avoid this, reduction in amount of subchannels from
16 (full bandwidth) to 8, 4, 2 or 1, will be accompanied with a reduction of 3, 6, 9
or 12 dBm, respectively, in the SU’s Tx power (unless the RSSI of the SU is below
the nominal RSSI level).
The ATPC menu enables viewing/updating the following parameters for all AUs:
4.5.2.4.1
ATPC Enable/Disable
The ATPC Enable/Disable parameter controls whether the ATPC algorithm will be
used to determine current optimal transmit level for each SU served by the Base
Station.
used to determine current optimal transmit level for each SU served by the Base
Station.
The default is Enable.
4.5.2.4.2
Optimal Uplink RSSI
The Optimal Uplink RSSI sets the target level at which all transmissions should
be received by the AU-ODUs for optimal performance.
be received by the AU-ODUs for optimal performance.
The range is -90 to -60 (dBm).
NOTE
The ATPC algorithm should always be enabled. The option to disable it is available to support
certain tests. After each reset, the Base Station boots with the ATPC enabled, disregarding its
status before the device was reset.
certain tests. After each reset, the Base Station boots with the ATPC enabled, disregarding its
status before the device was reset.