User's Manual

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8.3.7.2 Spectrum Management Measurements
The 600 Series Bridge performs two mean signal measurements per TDD cycle, per channel.
This mean measurement represents the mean received signal power for the 40 μS
measurement period.
The Spectrum Management algorithm collects measurements equally from all channels. This
process is called the Channel Availability Check (hereafter referred to by the acronym CAC).
The CAC uses a round-robin channel selection process to collect an equal amount of
measurements from each channel. It is important to note that the CAC measurement process
is not altered by the channel barring process. Measurements are still collected for all
channels irrespective of the number of barred channels.
8.3.7.3 Measurement Analysis
Spectrum Management uses statistical analysis to process the received peak and mean
measurement. The statistical analysis is based on a fixed, one minute, measurement
quantization period. Spectrum Management collects data for the specified quantization period
and only at the end of the period is the statistical analysis performed.
The analysis produces three key metrics for each channel:
o Peak of Means
o 99.9% Percentile of the Means
o Mean of Means
Peak of Means is the largest mean interference measurement encountered during the
quantization period. The peak of means is similar to the peak of peaks and is useful for
detecting slightly longer duration spikes in the interference environment.
99.9% Percentile of the Means is the value of mean interference measurement which 99.9%
of all mean measurements fall below, during the quantization period. The 99.9% percentile
metric is useful for detecting short duration repetitive interference that by its very nature has a
minimal effect of the mean of means.