User Manual
iSiteC BTS3601C CDMA Base Station
BTS Maintenance
Chapter 4 Fault Analysis and Locating
4-10
Fault cause
Fault location
Handling methods
Remarks
Abis signaling
link fault
-
Query the current alarms of BTS on
the OMC console or BTS local
maintenance console and check
whether any “Abis Signaling Link
Fault” alarm.
-
Please refer to “4.5.3 Abis
Signaling Link Fault” for fault
elimination measures.
1. After BTS startup, if the Abis
signaling link becomes faulty, BSC
will be unable to perform logic
configuration for BTS, which will
result in MS network access failure.
2 If the BTS has obtained correct
logic configuration, it will switch off
transmission signals of BTRM
corresponding to all sector carriers.
This will result in the failure of MS
access to the network.
The Cell has
not obtained
the BSC
logical
configuration
-
1. Check the configuration progress
report in the configuration process
via the [BTS Status] window on the
OMC console: If no progress reports
are available such as “Common
channel established successfully”
and “Overhead message updated
successfully”, the logic configuration
for this cell has not been completed.
-
2. Check the configuration process
report of the cell in the [BTS Status]
window from the OMC console: If a
process report “Cell deleted” is
prompted, the cell must have been
deleted.
If the cell has not obtained the
logic configuration, please
check the following items by
viewing relevant indicators,
querying board status and
alarm information, etc.
Check status of:
1. The MTRM for this cell;
2 The MBPM for this cell;
3.The Abis signaling link;
4.The BSC;
5. Configuration data for BTS
and BSC and make sure their
consistency.
1 If the cell has not obtained the logic
configuration (Namely, no pilot
channel, synchronization channel
and paging channel are established
in the cell), or the overhead message
has not been updated, the MS
access to the network will be
impossible.
2. Sometimes the cell may be
deleted due to lack of physical
equipment or due to mis-operations
(such as deleting a device by
mistake), and the MS cannot be
accessed to the network.
This cell is
blocked.
The logic configuration for the cell
has been completed, but the MS still
cannot access to the network. Please
check whether this cell has been
blocked.
Execute the command
micro>dsp
btsbrdstat
to query the status of
MTRM and check whether MTRM is
blocked.
If the cell is blocked, the MS
access to the network will be
impossible until the subscriber
unblocks the cell.
When a cell is blocked, the BTS will
switch off the transmission signals of
the BTRM corresponding to the
carrier of this cell, which will result in
the MS network access failure.
Abnormal
receiving
channel
1. The logic configuration for the cell
has been completed, but the MS still
cannot log on to the network. Please
check whether the receiving channel
is working normally.
2. Track air interface messages with
a CDMA test MS: If the MS cannot
receive any response from the BTS
after sending a registration message,
the inverse receiving channel of the
BTS must be faulty.
By viewing relevant indicators,
querying board status and
alarm information,
1. Confirm proper installation
of MFEM and MTRM, e.g.
inter-module cable
connection, water-proof
measures.
2. Check connection of
antenna & feeder.
3. Check BTRM status.
4. Check BTS physical
configuration data, e.g., cell
parameters and inverse
search parameters.
1. If the receiving channel of the BTS
is abnormal, the BER may become
too high and the MS may be
detached frequently.
2. When the MS is powered on, it will
send a power-on registration
message to the system. The BTS
cannot receive this message due to
faults with the receiving channel, so it
will send any response to the MS,
which causes MS registration failure.
3. After the registration fails, the MS
will enter the system determination
substate to re-acquire the system.
Once the system is acquired, the
power-on registration will be
activated again. This process is
repeated again and again but the MS
cannot access to the network.
