Taking Advantage of Multiple Handover Preparations to Improve Handover Performance in LTE Networks

LTE handover procedure supports multiple preparations feature. But the feature is of help to successful re-establishment after radio link failure during handover procedure. The recently announced results from a field test conducted in a downtown in North America show handover failure rate over 21% in dense LTE networks. In this paper, we propose Early Handover Preparation with Ping-Pong Avoidance (EHOPPPA) handover which utilizes multiple preparations feature for improving handover performance. With EHOPPPA handover, the UE can receive multiple Handover Command messages of multiple prepared target eNBs and select the best eNB by cell selection. Simulation results show that the proposed scheme can achieve about 60% reduction in handover failure rate and nearly 100% successful recovery rate from radio link failure during handover without increasing ping-pong rate.