Diversity Supervision - Ericsson CME 20 R6.1 Reference Manual

17

Diversity Supervision

The "Diversity Supervision" function supervises the signal strength
imbalance between the two diversity channels in an RBS with receiver
diversity.
The function is capable of detecting major faults in the radio receiver
paths or the receiver antenna system.
17.1 References
/GSM:05.08/
Whenever a reference is made to a function described in another chapter,
please refer to the table of contents to find the appropriate chapter.
17.2 Concepts
Measurement Period
Observation Period
Channel Utilisation Threshold The Channel Utilisation Threshold (CUT)
Channel Utilisation Ratio
Minimum CUR
EN/LZT 123 2697 R5A
1998-08-13
GSM Requirements 05.08 Phase 2 version
4.6.0
The Measurement Period corresponds to
the "reporting period" of the radio link
measurements as specified in /GSM 05.08/
. The Measurement Period is defined only
for dedicated channels. Basic channel
measurements on dedicated channels, as
the signal strength measurements, are
made for each Measurement Period
The Observation Period defines a time
window during which the signal strength
relationship between the two diversity
channels is observed before any decision
regarding a possible disturbance is taken.
is the criterion for an active dedicated
channel to be regarded as utilised. It is
that the receiver signal strength is above a
certain level on at least one of the
diversity channels. The Channel
Utilisation Threshold is characterised by
the required signal strength.
The Channel Utilisation Ratio (CUR) is
defined here as the relative rate of
utilisation of a dedicated channel or a set
of dedicated channels during a certain
period of time. The CUR is calculated per
observation period. (It is the same for
both of the receiver's diversity channels.)
The Minimum Channel Utilisation Ratio is
the lowest CUR at which the receiver
diversity is supervised. The minimum
CUR is applied to the entire transceiver
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Diversity Supervision
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