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LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
Single site verification:
Single site verification step ensures every single site can work normally.
Network tuning:
The main target of network tuning is to ensure the coverage, control interference
and clear basic handover problems. Normally network tuning is based drive test.
Network parameters optimization:
In network parameter optimization step, the main target is to ensure the KPI
performance by field test and KPI statistics analysis.
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
Weak coverage:
If the RSRP of pilot signal is very low, it is possible that UE can not camp in the cell
or UE can not trigger registration.
Weak coverage can also decrease the QoS of service, cause call drop sometimes.
Cross coverage:
Cross coverage can generate the phenomenon of an "island". Therefore, when a
call is connected to the island-shaped area far away from the eNodeB but still
served by the eNodeB, and the cells adjacent to this "island" are not set to the
neighboring cells of this cell during setting of cell handover parameters, call drop
may occur immediately once the UE leaves this "island". Moreover, even though a
neighboring cell is configured, call drop tends to occur as a result of untimely
handover as the "island" has a too small area.
Lack of dominant cell:
As a result of lack of dominant cell, handover occurs frequently, thus reducing
system efficiency and increasing possibility of call drop.
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
The figure in the slide shows the RSRP distribution of the best cell.
LTE Network Tuning
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The figure in the slide shows the distribution of PCI for the best cell.
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The distribution of UE transmission power reflects the distribution of uplink interference
and uplink path loss.
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It can be seen from the figure in the slide that the UE transmission power is lower than 10
dBm in normal situations, and will rise dramatically over 10 dBm only when there is an
uplink interference or coverage area edge. In comparison, a macro cell is more likely to
subject to uplink coverage restriction than a micro cell.
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As shown in Figure, Over coverage is caused by the cell whose PCI is 288.
Over Coverage will interfere with other cells and increase the call drop probability.
LTE Network Tuning
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LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
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LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
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Uplink and downlink are not completely separated, poor downlink channel quality not only
affects the downlink signaling demodulation. For example, incorrect PDCCH demodulation
affects the scheduling of uplink signaling, resulting in uplink signaling lost. Therefore, we
cannot think easily that the lost of uplink signaling is the result of poor downlink channel
quality.
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All the parameters can shown in GENEX Probe which is HUAWEI drive test software.
IBLER is initial BLER.
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LTE Network Tuning
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In the signaling trace result, UE sent several measurement reports to eNodeB by didnt
receive the handover command from eNodeB. Then call drop happened.
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LTE Network Tuning
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To confirm the problem, we can also check the neighboring cell configuration in eNodeB.
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In eNodeB side we can see that eNodeB received several MEASUREMENT REPORT and
sent RRC CONNECTION RECONFIGURATION(handover command). Whats more,
eNodeB sent HANDOVER REQUEST to the target eNodeB.
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In UE side we can see that UE sent several MEASUREMENT REPORT to eNodeB, but it
didnt receive RRC CONNECTION RECONFIGURATION(handover command) from
eNodeB.
LTE Network Tuning
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LTE Network Tuning
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LTE Network Tuning
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We can see that the time duration is 2 seconds in which the RSRP in target cell is 1dB
higher than RSRP in serving cell. But after the 2 seconds RSRP in serving cell decrease very
fast. So UE can not receive handover command due to bad downlink channel quality.
LTE Network Tuning
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LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
Mn is the measurement result of the neighboring cell.
Ofn is the frequency-specific offset for the frequency of the neighboring cell.
Ocn is the cell-specific offset (that is, CIO) for the neighboring cell.
Ofs is the frequency-specific offset for the serving frequency.
Ocs is the cell-specific offset for the serving cell.
Hys is the hysteresis for event A3.
Off is the offset for event A3.
LTE Network Tuning
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LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission
LTE Network Tuning
Confidential Information of Huawei. No Spreading Without Permission