Impact of reading system information in inbound handover to LTE femtocell

In recent standardization of 3GPP RAN, user equipments (UEs) attempting inbound handover to LTE Closed Subscriber Group (CSG) femtocells are required to read the system information of femtocells and report it to serving cell. One issue with this approach is that UE can´t receive the radio frames transmitted from the serving cell during the period. This paper evaluates service interruption time caused by reading system information of target Home eNB during handover evaluation period. We compare three measurement approaches intensively and provide helpful tips for reducing service interruption time. We show that autonomous measurement approach provides best performance in a dense femtocell deployment through simulation and it is very effective way for user equipment to make the best use of the timing of target Home eNB to reduce frame loss.