Separation Framework: An Enabler for Cooperative and D2D Communication for Future 5G Networks

Soaring capacity and coverage demands dictate that future cellular networks need to soon migrate towards ultra-dense networks. However, network densification comes with a host of challenges that include compromised energy efficiency, complex interference management, cumbersome mobility management, burdensome signaling overheads and higher backhaul costs. Interestingly, most of the problems, that beleaguer network densification, stem from legacy networks' one common feature i.e., tight coupling between the control and data planes regardless of their degree of heterogeneity and cell density. Consequently, in wake of 5G, control and data planes separation architecture (SARC) has recently been conceived as a promising paradigm that has potential to address most of aforementioned challenges. In this article, we review various proposals that have been presented in literature so far to enable SARC. More specifically, we analyze how and to what degree various SARC proposals address the four main challenges in network densification namely: energy efficiency, system level capacity maximization, interference management and mobility management. We then focus on two salient features of future cellular networks that have not yet been adapted in legacy networks at wide scale and thus remain a hallmark of 5G, i.e., coordinated multipoint (CoMP), and device-to-device (D2D) communications. After providing necessary background on CoMP and D2D, we analyze how SARC can particularly act as a major enabler for CoMP and D2D in context of 5G. This article thus serves as both a tutorial as well as an up to date survey on SARC, CoMP and D2D. Most importantly, the article provides an extensive outlook of challenges and opportunities that lie at the crossroads of these three mutually entangled emerging technologies.Comment: 28 pages, 11 figures, IEEE Communications Surveys & Tutorials 201

Coalitional Games with Overlapping Coalitions for Interference Management in Small Cell Networks

In this paper, we study the problem of cooperative interference management in an OFDMA two-tier small cell network. In particular, we propose a novel approach for allowing the small cells to cooperate, so as to optimize their sum-rate, while cooperatively satisfying their maximum transmit power constraints. Unlike existing work which assumes that only disjoint groups of cooperative small cells can emerge, we formulate the small cells' cooperation problem as a coalition formation game with overlapping coalitions. In this game, each small cell base station can choose to participate in one or more cooperative groups (or coalitions) simultaneously, so as to optimize the tradeoff between the benefits and costs associated with cooperation. We study the properties of the proposed overlapping coalition formation game and we show that it exhibits negative externalities due to interference. Then, we propose a novel decentralized algorithm that allows the small cell base stations to interact and self-organize into a stable overlapping coalitional structure. Simulation results show that the proposed algorithm results in a notable performance advantage in terms of the total system sum-rate, relative to the noncooperative case and the classical algorithms for coalitional games with non-overlapping coalitions

Quality of Service Improvement in Femto based Cellular Networks

A cellular network serve the high service demands of the indoor users it is very expensive to obtain macrocell coverage which results in requirement of new methods to solve problem of high capacity indoor coverage femto cell is one of the solutions. Deployment of femto cell networks embedded into macro cell coverage improves the coverage, capacity and quality of service in indoor environments. Due to its ad-hoc nature, the information about its density and location is not known a-priori. As femtos and macros share the same licensed spectrum, interference is one of the major problems observed and has to be mitigated. In this paper two existing channel allocation schemes such as opportunistic channel allocation scheme and orthogonal channel allocation scheme are discussed and their performance is compared to the proposed Max-SINR scheme. To reduce the interference further a self-organized and intelligent resource allocation is also proposed .Parameter such as average SINR experienced by each femto user is calculated by varying the percentage of active Femto cells in a network. Simulation results are carryout using MATLAB

Quality of Service Improvement in Femto based Cellular Networks

A cellular network serve the high service demands of the indoor users it is very expensive to obtain macrocell coverage which results in requirement of new methods to solve problem of high capacity indoor coverage femto cell is one of the solutions. Deployment of femto cell networks embedded into macro cell coverage improves the coverage, capacity and quality of service in indoor environments. Due to its ad-hoc nature, the information about its density and location is not known a-priori. As femtos and macros share the same licensed spectrum, interference is one of the major problems observed and has to be mitigated. In this paper two existing channel allocation schemes such as opportunistic channel allocation scheme and orthogonal channel allocation scheme are discussed and their performance is compared to the proposed Max-SINR scheme. To reduce the interference further a self-organized and intelligent resource allocation is also proposed .Parameter such as average SINR experienced by each femto user is calculated by varying the percentage of active Femto cells in a network. Simulation results are carryout using MATLAB