Mobility KPI

 Mobility is the key procedure for ensuring that users can move freely within a network, without dropping the call or session



  •  Intra-Frequency Handover :Within same LTE Frequency(Event A3 is triggered when a neighbor cell becomes better than the serving cell by an offset).
  • Inter-Frequency Handover :Different LTE Frequency(Event A4 is triggered when a neighbor cell becomes better than a threshold).
  • TRAT Handover :Between different Radio System Technology like LTE to 3G or 2G.(Event B1 & B2)
LTE Handover have two version: X2-Based and S1-Based

X2-Based :When Source and Target eNB are served within the same MME Pool.

S1-Based :When Source and Target eNB are served in different MME Pool.

Intra eNB Handover :Handover between two cells of same eNB.(S1 or X2 handover not required)

Preparation Phase :Admission Control and Resource Allocation.

Execution Phase :Detach from old cell and synchronize to new cell.

Admission Control Failure :Target site are congested, so it is not ready to accommodate the new UE.(In this case we need to Balance traffic between LTE carriers or offload it with the Neighbors.

TAC Issue : Wrong TAC defined.(Solution=Correct from the planning database.

X2 link Unable or not defined : Delete the neighbor Relation and ANR will automatically added.

Late HO + Early : Change the cell individual offset value accordingly.

Late HO=Modify CIO in +ve side.

Early=Modify CIO in -ve side. Also we can modify RET value. 

Ping Pong : Overshooting and many good signal cells will lead ping pong.(Solution=A2 or A3 event tuning. Down tilt or cell power reduction.)

S1 Interface Failure & One-way NBRs :Optimize missing neighbor relation. If  neighbors are one way, we can define it both way.

Downlink Coverage : Downlink Coverage issue means Coverage issue or Coverage related issue. So to Improve the coverage we have to modify the Reference Signal Power or we have to up tilt the source/target. We can reduce the timer and offset as well.

IRAT Handover(Inter Radio System Technology) : 








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