Diagnostics and Fault Handling
27.2.2
Fault Filtering
Disturbances are detected by the supervision function. All disturbances
are filtered before a fault is considered to be present or absent. The
filtering function is adapted to each fault situation for optimum
performance. For example, the following parameters (or combinations
of) may be used for the filter function:
•
The reception frequency of disturbances
−
A frequency which is too high is considered to be a fault
•
The measurement value of a parameter
−
A parameter exceeding a threshold is considered to be a
fault
•
Time
−
A condition which is valid for too long is considered to
be a fault
27.2.3
Fault Evaluation
Detected faults are evaluated to determine the underlying fault. This is
done by analysing faults reported on a low level (specific hardware
units) and mapping them to a high level (RUs and MOs and the entire
RBS), thus taking the complete fault situation into account.
27.2.4
Fault Classification
Faults detected by an MO are classified according to:
•
Severity
−
Either affects (may affect) functionality of the MO or
does not affect functionality of the MO
•
Fault origin
−
Either internal or external to the MO
−
Either internal or external to the RBS
27.2.5
Fault Localisation
When detecting a fault, the RBS automatically evaluates the fault
situation and indicates the suspected faulty RU. The fault status of the
RBS is updated with this information.
When a fault is pin-pointed to a specific RU, or to the entire RBS, this
is visually indicated as specified in chapter Operational and
Maintenance Terminal.
27.2.6
Local Action
The impact of certain faults can sometimes be minimised by performing
some suitable local action autonomously within the RBS. Permitted
actions are:
166 (306)
EN/LZT 123 2697
R5A
1998-08-13
© Ericsson Radio Systems AB
— All Rights Reserved —
