Nera WILINK I System Manual page 115

Chapter 4 - Operation and Administration
2 The Downlink Frequencies of all Channels of the same AU should belong
to the same Frequency Bands Group (see Section 4.7.5).
Admin Status: The Admin Status must be disabled to enable changes in the
Configured ODU Frequency Band of an associated ODU. If the Configured
ODU Frequency Band differs from the actual band supported by the ODU, a
mismatch trap will be sent by the AU upon trying to associate it with a
Channel and the association will be rejected.
The Admin Status of all Channels belonging to the same AU must be disabled
to enable a configuration change in the Bandwidth parameter.
The Show menu includes also the following read-only parameters:
Tx Power: As configured in the Associated ODU.
Associated Radio Cluster: As configured in the Associated ODU.
Uplink (Rx) Frequency: Computed from the configured Downlink (Tx)
Frequency according to the Duplex Separation of the applicable Frequency
Band.
Frequency Band: The Configured ODU Frequency Band. If there is a
mismatch between the Configured ODU Frequency Band and its actual band,
both values will be displayed.
Operational Status
4.8.4.3.4 Multirate Parameters
WILINK I employs a multirate algorithm to dynamically adapt the modulation
scheme and Forward Error Correction (FEC) coding to actual link conditions. The
algorithm is managed by the AU taking into account also information received
from the served SUs. Optimal values are calculated separately for the uplink and
downlink for each SU, taking into account also the applicable QoS requirements.
MAP messages transmitted to the SUs include information on the uplink rate that
should be used by each SU for its next transmission.
The Basic Rate is the minimum rate to be used by the Multirate algorithm. This is
also the rate to be used for downlink broadcasts and multicasts. Broadcasts and
multicasts messages are not acknowledged, so that the ARQ mechanism cannot
be used and there is no way to guarantee that all intended recipients will receive
them properly. In addition, AU's multicasts and broadcasts are sent to multiple
recipients with different link qualities. Therefore, it is preferable to use a relatively
low rate for these transmissions, thus reducing the probability of errors and
increasing the likelihood that all intended recipients will receive them properly.
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WILINK I MODULAR BASE STATION SYSTEM MANUAL