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Dear expert
pls your support to check the reasons of following call drop
1- M3101A:Call Drops due to CONN FAIL Received on TCHF (Traffic Channel) in Stable State (Radio Link Failure)
2-M3201A:Call Drops due to CONN FAIL Received on TCHH (Traffic Channel) in Stable State (Radio Link Failure)
thanks
Pls check either these drops were due to UL quality or DL Quality? then you can further investigate either the issue is with DL or UL.
Hedex Description:
SACCH Multi-Frames
This parameter determines whether an uplink radio link is faulty. Each time the BTS fails to decode measurement reports sent by the MS over the SACCH, the value of this parameter decreases by 1. Each time the BTS successfully decodes measurement reports sent by the MS over the SACCH, the value of this parameter increases by 2. If the value of this parameter is 0, the BTS assumes that the uplink radio link is faulty. If the value of M3101A:Call Drops due to CONN FAIL Received on TCHF (Traffic Channel) in Stable State (Radio Link Failure) is large, a large number of calls drop due to poor radio environment. In this case, set this parameter to a larger value.
Radio Link Timeout
This parameter determines the time for disconnecting a call when an MS fails to decode the messages over the SACCH. Once a dedicated channel is allocated to an MS, the counter S is enabled and the initial value is set to the value of this parameter. Each time the MS fails to decode an SACCH message, the counter S decreases by 1. Each time the MS correctly decodes an SACCH message, the counter S increases by 2. When the counter S is equal to 0, the downlink radio link is considered as failed. Therefore, when the voice or data quality deteriorates to an unacceptable situation and cannot be improved using power control or channel handover, the connection is re-established or released. If the value of M3101A:Call Drops due to CONN FAIL Received on TCHF (Traffic Channel) in Stable State (Radio Link Failure) is large, a large number of calls drop due to poor radio environment. In this case, set this parameter to a larger value
Check the with the transmission guys if the site did had any problem(E1 high BER or etc). This problem is with one cell only or with all cells?
One specific hour or constant?
Alarms in the time the problem persisted.
Try giving a reset to the BTS(usually fixed problems).
Check also if the drops came from one specific UE or are distributed among all users.
Check if there was any core parameter change.
B/R
Quote:
Originally Posted by sad_RNP
Dears,
which parameters could help to optimize call drop due to:
1- M3101A:Call Drops due to CONN FAIL Received on TCHF (Traffic Channel) in Stable State (Radio Link Failure)
2-M3201A:Call Drops due to CONN FAIL Received on TCHH (Traffic Channel) in Stable State (Radio Link Failure)