1. The eNodeB handover contains 7 events:
A1: Indicates that the signal quality of the serving cell is higher than a specified threshold. When this condition is met, the eNodeB stops inter-frequency and inter-RAT measurements. This command is used to stop the eNodeB from measuring inter-frequency and inter-RAT measurements.
A2: Indicates that the signal quality of the serving cell is lower than a specified threshold. When an event that meets this condition is reported, the eNodeB starts inter-frequency and inter-RAT measurements to start inter-frequency and inter-RAT measurements.
A3: Indicates that the quality of the intra-frequency neighboring cell is higher than that of the serving cell. When the event that meets this condition is reported, the source eNodeB starts a handover request (triggering an intra-frequency handover).
A4: Indicates that the quality of the inter-frequency neighboring cell is higher than a certain threshold. When the event that meets this condition is reported, the source eNodeB starts the inter-frequency handover request (triggering the inter-frequency handover).
A5: Indicates that the quality of the serving cell is lower than a specified threshold and the quality of the neighboring cell is higher than a specified threshold.
B1: If the inter-RAT neighboring cell threshold is higher than a specified threshold and the event is reported, the source eNodeB starts an inter-RAT handover request.
B2: Indicates that the quality of the serving cell is lower than a specified threshold and the quality of the inter-RAT neighboring cell is higher than a specified threshold.
2. Three phases of the handover:
Measurement: The UE performs measurement based on the eNodeB configuration and reports the measurement results to the eNodeB.
Decision: The eNodeB determines whether to trigger a handover based on the measurement result reported by the UE.
Run the following command: Based on the decision result, the eNodeB controls the handover from the UE to the target cell.
3. The entire handover process includes the following six steps:
a．Measurement control (when the eNodeB delivers a measurement control message to the UE,UE to meet the conditions of the event)
b．Reporting measurement results
c．Handover decision
d．Handover resource preparation
e．Handover execution
f．Source Cell Resource Release
