LTE Handover Analysis

The L.HHO.Prep.FailOut.NoReply counter is incremented by 1 each time the source eNodeB does not receive a HANDOVER REQUEST ACKNOWLEDEG message or a HANDOVER PREPARATION FAILURE message from the target eNodeB

• TRUE

• FALSE

Handover execution is successful after source eNodeB received (    ) signaling message

• Handover Request Acknowledge

• UE Context Release

• Path Switch Request Acknowledge

• RRC Connection Reconfiguration Complete

Which of the following is NOT the information element in RRC handover command (mobility control information)?

• Target cell PCI

• PDCP Sequence Number of uplink and downlink

• Radio resource configuration

• Handover security configuration

Which of the following can be considered as the symptom of delayed handover?

• After receiving a handover command, a UE experiences a radio link failure (RLF) during the handover to the target cell. Then, the UE is handed over back to the source cell during RRC connection reestablishment

• A UE camps on the target cell for a short period and the RLF happen. UE reestablish the RRC connection to source cell

• After UE sends measurement report, it doesn’t receive any handover commands

• UE doesn’t send measurement report, RLF happens in source cell, and RRC establishment setup to target cell also fails

S1 initial context setup request carries a number of information, includes (    )

• IP address assigned to UE

• QCI for the default EPS bearer

• NAS PDU of “attach request”

• UE Aggregate Maximum Bit Rate

E-RAB includes both the E-RAB radio bearer and corresponding S1 bearer. Only abnormal releases of E-RAB radio bearers can cause call drops and the call drop rate is calculated.

• TRUE

• FALSE

LTE base station support the statistics of the reasons E-RAB release for the sub value and sub QCI includes?

• L.E-RAB.AbnormRel.Radio

• L.E-RAB.AbnormRel.TNL

• L.E-RAB.AbnormRel.Cong

• L.E-RAB.AbnormRel.HOFailure

What are the typical call drop reasons caused by radio?

• Poor channel quality

• Re-synchronization failure

• Signaling interaction failure

• Re-establishment failure

Which of the followings belogs to common cause of delayed handover?

• Handover parameters is not reasonable

• UE terminal issues

• Neighbor cell not configured / mismatch

• Poor quality of radio channel

Ping-pong handover leads to a decrease in road test performance due to UE outage events near the ping-pong handover.

• TRUE

• FALSE