Nortel DualMode 800, Maintenance Manual

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Performing tests using the DCSM in the directed mode 9-3
Wireless Solutions DualMode 800 Enclosure Maintenance Manual MTX08
specify if monitoring is to be performed for ACCHs, DCCHs, or both. In the
event that both CCH types are required to be monitored, the periodic audit
will proceed in a round robin fashion by first monitoring all the ACCHs
within the scope of the command, and then all the DCCHs.
When a DCSM is monitoring an ACCH, it detects:
a. loss of CCH synchronization
b. SID errors
c. mismatches between the CCH onto which the ICP commanded the
cell site monitor to lock and the CCH onto which the cell site monitor
is locked
When a DCSM is monitoring a DCCH, it also detects:
a. errors in the number of F-BCCH slots
b. errors in the number of E-BCCH slots
c. errors in the E-BCCH RCI locked
These errors are communicated to the CM as unsolicited messages.
When MON is ON, the ICP periodic audit process entails commanding the
DCSM to monitor the current CCH in sequence. Once the DCSM mobile is
locked onto the CCH, the ICP commands an audit order to be issued over the
CCH. If the audit order response is not received over the reverse CCH, then a
retry is attempted. Two consecutive failures results in the ICP reporting an
unsolicited audit order failure message to the CM. The message type
identifies either the CCH or the DCSM as the suspected cause of the failure.
OMs are consulted to determine if originations, or page responses, or
registrations were occurring during the period of the audit for the CCH under
test. If these OMs were being incriminated, then a failure of the DCSM is
presumed, otherwise a failure of the CCH is presumed.
If the DCSM mobile does not successfully lock onto the CCH, a new
unsolicited message is sent to the CM with a message type indicating the
failure to synchronize.
The goal is to revisit each CCH approximately every two minutes.