Dynamic Virtual Cell Design Based On User Centric Approach In 5G Ultra Dense Network

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.It is envisioned that 5G(Fifth Generation)cellular technology will provide ADSL(Asymmetric Digital Subscriber Line)like user experience.Therefore,5G will also need a massive paradigm shift to overtake 4G for further increase in data rates and decrease latency.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).As a result,many current and new challenges will also arise including interference,handovers,resource allocation and back-hauling etc.To improve the spatial reuse,FAPs will be deployed in a co-channel mode by using the same frequency spectrum used by MBSs(Macro Base Stations).Consequently,severe interference will be caused due to hyper dense deployment of adjacent FAPs,coupled with excessive handovers among cells.Based on the investigations of predicted challenges and requirements of 5G UDN,this thesis has proposed a novel architecture that breakdowns the traditional cellular architecture.In our dissertation,we define UCUDN(User Centric Ultra Dense Network)by introducing the novel VC(Virtual Cell)design.As,dynamic VC forming/reforming is a core function of our proposed UCUDN architecture,we consider UCN(User Centric Network)approach for VC forming.Therefore,VC ID remain same and moves with UE(User Equipment).As a result,user could enjoy stable,satisfactory,secure and high speed cellular network services that will follow his movement.Furthermore,we provide methods for mobility management by reducing extra handovers and decrease interference by applying FFR(Fractional Frequency Reuse)scheme.We have evaluated the proposed VC scheme and compared our results with LTE network through LTE System Level Simulator based on MATLAB.We achieved our goals with low HOF(Handover Failure)rate and PP(Ping-Pong)rate for our proposed VC based UCUDN.In addition,by using low overhead FFR scheme in VC,interference is mitigated and high SE(Spectrum Efficiency)targets are achieved.In comparison to existing cellular architecture,user-centric based VC design,in future 5G UDN,will provide several times more SE by efficiently managing interference and enhancing overall network throughput.It will facilitate to accomplish the future demands that all people can access and share information(ubiquitous connectivity),connect effortlessly with the rest of the world using ultra-high speed wireless broadband,not only when they are at home or office but also on-the-go(e.g.on their way to work,while using public transport or driving their cars).Furthermore,VC design based on FFR scheme will make it possible for users to achieve high QoE(Quality of Experience)at both outdoor and indoor environments with low signaling overhead in future 5G UDN.