User manual

Chapter 2 - Managing a Single Device/Cell Service Parameters Page
AlvariCRAFT Device Manager 126 User Manual
the MIR/CIR values employed by the MIR algorithm will be calculated as an
average.
The average rates (for uplink and downlink) are calculated periodically. If the
difference between the current average rate and the previous average rate exceeds
a predefined percentage (Threshold Percentage) from the configured rate and the
current average rate is lower than a specific threshold (Threshold Rate), then the
respective MIR/CIR values for uplink or downlink will be recalculated.
Since the used MIR/CIR values must be calculated for both uplink and downlink,
there will be two values for MIR (Used Uplink MIR and Used Downlink MIR) and
two values for CIR (Used Uplink CIR and Used Downlink CIR). If at least one of
these four MIR/CIR values is updated, a reassociation is required in order to
inform the AU about the new MIR/CIR values. After reassociation, both units (AU
and SU) will work with synchronized values for MIR/CIR.
The following formula is used for calculating the applicable rates:
Where:
UsedRate = Applicable uplink/downlink MIR or CIR
PIF = Proportional IR Factor
AvgRate = Average Rate
ConfiguredRate = Configured uplink/downlink MIR or CIR
ThrRate = Threshold Rate
The formula for the average rate is:
Where
F
i
= Number of frames sent on modulation i
R
i
= Rate in Mbps for modulation i
Examples:
UsedRate
PIF AvgRate 100 IFF–ThrRate+
ThrRate 100
-------------------------------------------------------------------------------------------------------
ConfiguredRate=
AvgRate
F
i
R
i

i 1=
8

F
i
i 1=
8

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