A seamless voice call handover scheme for next generation cellular network

This paper proposes the world first complete voice call handover scheme between the 3G LTE and 3G CS systems. To achieve seamless handover, a powerful network entity called FW_MME is proposed. Features of the FW_MME contribute to reducing handover service interruption time; hence the resulting voice call handover performance is also improved. The evaluation result shows that the proposed FW_MME exclusively meets the strict service interruption time requirement which is smaller than 300 ms, whereas other conventional handover schemes spend more than twice large time in voice call handover.