LTE: Use of Event B1, while handling measurement reporting ?

Question

Since both the events B1 and B2 are used for Inter RAT measurement reporting. Which one is chosen by eNodeB and on what basis ? Is there any dependency on UE capability for that ?

Answer 1

Event B1 is being used for Inter-RAT measurement report triggering event.
As per specification: Event B1 is used when Inter-RAT neighbor becomes better than the threshold. There are following inequality conditions are given which need to be fulfilled.

Entering Condition: Mn + Ofn - Hys > Thresh
Leaving Condition: Mn + Ofn + Hys < Thresh.

where "Mn" is measurement result of Inter-RAT neighbor cell and "Ofn" is frequency specific offset of the frequency of the inter-RAT neighbor cell. "Hys" is the hysteresis parameter for this event (i.e. Event B1)