| In the last few decades, the previous four cellular generations have overtaken each other one by one with a terrific paradigm shift in technology that has ruined the backward compatibility. 4G-LTE/LTE-A (Forth Generation-Long Term Evolution/Long Term Evolution-Advanced) has already overtaken 3G (Third Generation) with high data rate and low delay based on flat IP network architecture. With the developments in cellular technologies, users and their demands are growing exponentially due to high speed internet services in the form of online multimedia streaming, 3D video, virtual reality, social networking, e-banking, interactive gaming and IoT (Internet of Things). New wireless technologies bring new mobility scenarios and extend the mobility objects.As one of the promising technology of 5G network, UDN (Ultra Dense Network) will play a key role in increasing not only the average user throughput but also the system capacity with hyper dense deployment of small cells especially in the form of FAPs (Femto Access Points). With the trend of network dense deployment, it is expected to provide high data rate,low signaling overhead and low delay in future 5G. Because of these issues, UDN which leads to frequent measurement, intolerable handover failure (HOF) rate.According to Virtual Cell (VC) forming/reforming architecture, we consider a User Centric Network (UCN) that breakdowns the traditional cellular architecture to compare with the LTE system. VC is a large cell, consisting of many several femtocells to provide coverage and borderless services, which is perhaps, a promising solution to mobility management in 5G UDN systems. Our simulation results show that with different parameter settings (TTT, offset), the handover failure (HOF) of VC scheme decreased compared with the LTE system. |
