When eNB sends measObjectToRemoveList, reportConfigToRemoveList, measIdToRemoveList IEs in RRCconnectionReconfiguration?

Question

What are the triggering conditions for eNB to send measObjectToRemoveList, reportConfigToRemoveList and measIdToRemoveList IE's in RRC connection Reconfiguration message?

Answer 1

In case of inter frequency LTE handover, when user is forcefully moved from one frequency to another frequency, target eNodeB may ask to delete the measurement object which are irrelevant. This case was related to mobility load balancing.

Answer 2

Hi,
We can take one more example where UE is initially configured with measurement events A1,A2,A4 with some thresholds and some measurement ids,Now if eNodeB receives the measurement report for A1(serving cell is better than configured threshold) then eNodeB may configure UE again with measurement event A4 with some higher threshold,so that to have neighbouring info in NRT.To do that eNodeB may remove earlier A4 event and ask UE to remove reportconfigID in reportConfigToRemoveList.So with respect to this report config id EnodeB will send respective measurement object id and measurement id in measObjectToRemoveList and measIdToRemoveList respectively.