Intra Lte Handover 5xgn

Intra-LTE Handover Connected ModeSubtitle Lato Semibold Ahmad Zubair

Measurements in Connected Mode  UE in RRC Connected and ECM connected  Step 1 : UE measures signal levels of serving and neighbors and reports to eNB  Step 2 : Serving eNB can use the measurements to request a handover to neighboring cell

Measurement Procedure

 eNB sends RRC Connection Reconfiguration message to specify measurements to UE.  The message contains measurement configurations which include LTE carrier frequency to measure and downlink bandwidth. It also contains reporting configurations which tells the mobile when to report the results  The UE acknowledges and makes measurements.  UE sends measurement report which identifies cell(s) by PCI

RRC Connection Reconfiguration message (part)

Measurement Reporting

Measurement reporting can be periodic with period from 120 milliseconds to 60 minutes More often, measurement reports are sent when an event is triggered which occurs when the signal levels cross certain thresholds

 The eNodeB determines whether to trigger coveragebased intra-frequency handover based on event A3 in the measurement result.  Event A3 indicates that the signal quality/level in a neighboring cell is better than that in the serving cell  Trigger condition: Mn + Ofn + Ocn - Hys > Ms + Ofs + Ocs + Off

Parameters

IntraFreqHoA3Offset

MO : IntraFreqHoGroup Parameter : IntraFreqHoA3Offset Parameter Name : Intrafreq handover offset Description : Indicates the offset for event A3. If the parameter is set to a large value, an intra-frequency handover is performed only when the signal quality of the neighboring cell is significantly better than that of the serving cell and other triggering conditions are met. For details, see 3GPP TS 36.331. This parameter applies only to LTE FDD and LTE TDD.

GUI Value Range : -30~30 Unit: 0.5 dB Recommended value: 2 Network value : 3 dB

IntraFreqHoA3Hyst

MO : IntraFreqHoGroup Parameter : IntraFreqHoA3Hyst Parameter Name : Intrafreq handover hysteresis Description : Indicates the hysteresis for intra-frequency handover

event A3. This parameter decreases frequent event triggering due to radio signal fluctuations and reduces the probability of handover decision errors and ping-pong handovers. A larger value of this parameter results in a lower probability. The hysteresis for event inter-frequency handover event A3 is the same as the value of this parameter. For details, see 3GPP TS 36.331

GUI Value Range : 0~30 Unit: 0.5 dB Recommended value: 2

Cell individual offset

MO : EutranIntraFreqNCell Parameter : CellIndividualOffset Parameter Name : Cell individual offset Description : Indicates the cell individual offset for the intrafrequency neighboring cell, which is used in evaluation for handovers. It affects the probability of triggering intra-frequency measurement reports. A larger value of this parameter indicates a higher probability. For details, see 3GPP TS 36.331. This parameter applies only to LTE FDD and LTE TDD. GUI Value Range : -24 to 24 Unit: dB Recommended value: 0

IntraFreqHoA3TimeToTrig

MO : IntraFreqHoGroup Parameter : IntraFreqHoA3TimeToTrig Parameter Name : Intrafreq handover time to trigger Description : Indicates the time-to-trigger for intra-frequency handover event A3. When the UE detects that the signal quality in the serving cell and that in at least one neighboring cell meet the entering condition, it does not immediately send a measurement report to the eNodeB. Instead, the UE sends a report only when the signal quality meets the entering condition throughout the time-to-trigger. This parameter helps decrease the number of occasionally triggered event reports, the average number of handovers, and the number of incorrect handovers, preventing unnecessary handovers. The time-to-trigger for inter-frequency handover event A3 is the same as the value of this parameter GUI Value Range : 0 to 5120 ms Unit: ms Recommended value: 320 ms

Signaling

S1 Based Intra LTE Handover

X2 Based Intra LTE Handover

Counters

Calibri Body Divider Slide Calibri Light Subtitle

X2 Based Handover Preparation

X2 Based Handover Preparation Failures

X2 Based Handover Execution

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