3rd Generation Partnership Project Long Term Evolution (3GPP-LTE) is focusing towards aggressive frequency reuse i.e. reuse of 1 so that we can get maximum number (all available spectrum) within a cell. Now, the major hindrance is... more
3rd Generation Partnership Project Long Term Evolution (3GPP-LTE) is focusing towards aggressive frequency reuse i.e. reuse of 1 so that we can get maximum number (all available spectrum) within a cell. Now, the major hindrance is co-channel interference which increases dramatically due to nearby adjacent co-channel cell and most especially for cell edge users. Traditional frequency reuse concept for interference management doesn’t provide satisfactory coverage and rate. In this paper, FFR is purposed as a candidate for interference management and its comparative evaluation over Traditional frequency reuse on the basis of two parameter metrics viz. probability of coverage and probability of acceptance rate is done. We observe that FFR has relatively better performance in 3GPP-LTE downlink.
This paper deals with the transmission of group-oriented services, considered as the main value-added for the future 4G broadband wireless systems. In this scenario, the design of proper resource allocation strategies is a key issue in... more
This paper deals with the transmission of group-oriented services, considered as the main value-added for the future 4G broadband wireless systems. In this scenario, the design of proper resource allocation strategies is a key issue in order to offer high quality services to involved users and to efficiently exploit the available radio resources. In this paper we extend the works existing in literature by evaluating the impact of frequency selectivity on the performance in terms of spectral efficiency achieved when group-oriented services are provided in Long Term Evolution (LTE) and LTE-Advanced (LTE-A) systems. We conducted exhaustive simulation campaigns in order to define the scenarios that could benefit of the exploitation of frequency selectivity in multicast resource allocation. We investigated single- and multi-group scenarios with different application profiles, such as real time video flows, and we considered several deployment cases addressing different channel bandwidth and user configurations.
In this work, we investigate the issue of fair resource allocation in relay-enhanced wireless networks. Our focus is on Type-1 relays as proposed for LTE-Advanced. The latter operate as inband relays, i.e., the backhaul and access link... more
In this work, we investigate the issue of fair resource allocation in relay-enhanced wireless networks. Our focus is on Type-1 relays as proposed for LTE-Advanced. The latter operate as inband relays, i.e., the backhaul and access link must share resources in the time domain. For the case of full buffer traffic on the downstream, we demonstrate how the data flow
In this work, we revisit the issue of fair resource allocation in relay-enhanced wireless networks. Our focus this time is on Type-1a relays as proposed for LTE-Advanced. The latter operate as out-band relays, i.e., the backhaul and relay... more
In this work, we revisit the issue of fair resource allocation in relay-enhanced wireless networks. Our focus this time is on Type-1a relays as proposed for LTE-Advanced. The latter operate as out-band relays, i.e., the backhaul and relay access link use separate carrier frequencies. If carrier aggregation is applied at the macro base station, the backhaul carrier may also contain
This paper provides a view on the technologies being considered for Long Term Evolution-Advanced (LTE-Advanced). The evolution from third generation (3G) to fourth generation (4G) is described in terms of performance requirements and main... more
This paper provides a view on the technologies being considered for Long Term Evolution-Advanced (LTE-Advanced). The evolution from third generation (3G) to fourth generation (4G) is described in terms of performance requirements and main characteristics. The main technologies for LTE-Advanced are explained, together with possible improvements, their associated challenges, and some approaches that have been considered to tackle those challenges. By the design and optimization of upcoming radio access techniques and a further evolution of the existing system, the Third Generation Partnership Project (3GPP) had laid down the foundations of the future Long Term Evolution (LTE) advanced standards the 3GPP candidate for 4G. The various technology components like wideband transmission and spectrum sharing, multi antenna solutions, coordinated multiple transmission/reception (CoMP) and relaying, introduced to meet the requirements for LTE Advanced systems, have been discussed.
Multicast services over Long Term Evolution (LTE) have recently attracted the interest of the research community. Particular attention has been put on handling fairness requirements of multicast users and experienced channel quality.... more
Multicast services over Long Term Evolution (LTE) have recently attracted the interest of the research community. Particular attention has been put on handling fairness requirements of multicast users and experienced channel quality. Conventional Multicast Scheme (CMS), Opportunistic Multicast Scheme (OMS), and multicast subgroup formation are the principal policies adopted to address this research issue. Little attention has been given so far to multicarrier systems like LTE-Advanced although the need for solutions appropriate to this system is strongly felt. In this paper we design radio resource management policies for the efficient delivery of multicast services in multicarrier LTE-Advanced systems and show how the relation between fairness and system efficiency can be controlled. Concerning the system resource management, game theoretic bargaining solutions are considered to best model fairness and efficiency (expressed in terms of throughput).
Long Term Evolution (LTE) is considered the most promising cellular system able to support the growing demand of multicast services (e.g., IPTV, video streaming) over mobile terminals. The design of effective strategies for the management... more
Long Term Evolution (LTE) is considered the most promising cellular system able to support the growing demand of multicast services (e.g., IPTV, video streaming) over mobile terminals. The design of effective strategies for the management of these applications is still an open issue, especially in scenarios where several multicast streams are simultaneously transmitted in a cell. In this paper we propose different resource allocation policies for the delivery of multicast scalable video flows. Such policies efficiently exploit the multi-user diversity and the frequency selectivity in order to match the requirements of both users and providers. The performance of the proposed strategies is analyzed through simulations by evaluating different cell deployment and user load environments and by focusing on spectral efficiency, throughput, fairness, and amount of resources needed for multicast service delivery. The last parameter is important in practical scenarios where multicast services share the available resources with other flows, e.g., unicast services.
"This paper addresses the design of an adaptive resource allocation policy for the efficient delivery of multicast services in Long Term Evolution (LTE) systems. The proposed approach overcomes the intrinsic inefficiencies of... more
"This paper addresses the design of an adaptive resource allocation policy for the efficient delivery of multicast services in Long Term Evolution (LTE) systems.
The proposed approach overcomes the intrinsic inefficiencies of Conventional Multicast Scheme (CMS) related to the different channel quality experienced by the involved users.
The basic idea is to split any multicast group into subgroups and apply subgroup-based adaptive modulation and coding schemes, which enable a more efficient exploitation of multi-user diversity.
The distribution of users into subgroups is determined by the solution of an optimization problem, aiming to improve the network throughput while guaranteeing fairness among multicast members."
Relay enhanced networks are expected to fulfill the demanding coverage and capacity requirements in a cost-efficient way. Type 1 inband relaying is now being standardized as an integral part of 3GPP LTE-Advanced. This type of relay nodes... more
Relay enhanced networks are expected to fulfill the demanding coverage and capacity requirements in a cost-efficient way. Type 1 inband relaying is now being standardized as an integral part of 3GPP LTE-Advanced. This type of relay nodes supports a relaying mode where the relay link transmission is time-division multiplexed with the access link transmission, whereas macro users share the same resources with the relays. Hence, system performance depends strongly on the resource sharing strategy among and within the links. Besides, in order to fully exploit the benefits of relaying, the inter-cell interference, which is increased due to the presence of relay nodes, should be limited via a proper power control scheme on each link. Therefore, an optimization of both the resource sharing and power control strategy is required to enhance the overall performance of relay networks. In this paper, performance evaluation of two-step resource sharing and power control optimization is carried out within the LTE-Advanced uplink framework in urban and suburban scenarios. Furthermore, we propose a combination of scheduling based on the number of relay-served users and throughput throttling achieving max-min fairness. Results show that the proposed scheme achieves significant throughput gains and high system fairness.
In this paper, we address the definition of a low-complexity subgroup formation algorithm for multicast data delivery in Long Term Evolution (LTE) networks. With this aim, we extend the subgroup merging scheme (SMS), designed for generic... more
In this paper, we address the definition of a low-complexity subgroup formation algorithm for multicast data delivery in Long Term Evolution (LTE) networks. With this aim, we extend the subgroup merging scheme (SMS), designed for generic Orthogonal Frequency Division Multiple Access (OFDMA) systems, by proposing two low-complexity subgroup formation schemes, named L-SMS and L-eSMS. Such schemes are tailored to exploit the great potentialities of LTE systems. Specifically, L-SMS is proposed in order to improve the scalability of SMS by handling a more efficient subgroup formation scheme with a computational cost which does not depend on the multicast group size. The L-eSMS also improves the resource assignment phase with the aim to achieve better near-optimal performance compared to L-SMS. Through simulations, we evaluated the effectiveness of the proposed schemes in different cell deployment and multicast configuration scenarios. The achieved results underlined that the proposed L-eSMS is well designed in order to guarantee performance close to the optimal one.
Device-to-Device (D2D) communication is a new technology that offer many advantages for the LTE-advanced network such us wireless peer-to-peer services and higher spectral efficiency. It is also considered as one of promising techniques... more
Device-to-Device (D2D) communication is a new technology that offer many advantages for the LTE-advanced network such us wireless peer-to-peer services and higher spectral efficiency. It is also considered as one of promising techniques for the 5G wireless communications system and used in so many different fields such as network traffic offloading, public safety, social services and applications such as gaming and military applications. The goal of this paper is to present advances on the current 3GPP LTE-advanced system related to Device-to-Device (D2D). In this paper, we provide an overview of the D2D types based on the communication spectrum of D2D transmission, namely Inband D2D communication and Outband D2D communication. Then we present the advantages and disadvantages of each D2D mode. Moreover, architecture and protocol enhancements for D2D communications under LTE-A network are described.
This paper summarizes four novel advanced antenna concepts explored in the framework of the WINNER+ project. The concepts are related to multiuser MIMO communication in cellular networks, focusing on the acquisition and application of... more
This paper summarizes four novel advanced antenna concepts explored in the framework of the WINNER+ project. The concepts are related to multiuser MIMO communication in cellular networks, focusing on the acquisition and application of channel state information (CSI) at the transmitter in time-division-duplex (TDD) mode. The concepts include new ideas for CSI modeling and sounding for the purposes of multiuser precoding, and methods for pilot signal design with the aim to support the estimation of different CSI quantities. Furthermore, a new relaying strategy for terminal-to-terminal communication is described. All the ideas are feasible for adoption into practical upcoming communication systems such as LTE-Advanced, and most of the proposed concepts have only a minor impact on standards. Our study indicates that the CSI at its best is not only about estimating the channel responses between different antenna pairs. What counts is the nature of the intended communication link as well ...
LTE and LTE-Advanced have been optimized to deliver high bandwidth pipes to wireless users. The transport mechanisms have been tailored to maximize single cell performance by enforcing strict synchronism and orthogonality within a single... more
LTE and LTE-Advanced have been optimized to deliver high bandwidth pipes to wireless users. The transport mechanisms have been tailored to maximize single cell performance by enforcing strict synchronism and orthogonality within a single cell and within a single contiguous frequency band. Various emerging trends reveal major shortcomings of those design criteria: (1) The fraction of machine-type-communications (MTC) is growing fast. Transmissions of this kind are suffering from the bulky procedures necessary to ensure strict synchronism. (2) Collaborative schemes have been introduced to boost capacity and coverage (CoMP), and wireless networks are becoming more and more heterogeneous following the non-uniform distribution of users. Tremendous efforts must be spent to collect the gains and to manage such systems under the premise of strict synchronism and orthogonality. (3) The advent of the Digital Agenda and the introduction of carrier aggregation are forcing the transmission syste...
This paper addresses the interference management problem in the context of LTE-Advanced femtocells. Due to the expected large number of user-deployed cells, centralized network planning becomes increasingly less viable. Consequently, we... more
This paper addresses the interference management problem in the context of LTE-Advanced femtocells. Due to the expected large number of user-deployed cells, centralized network planning becomes increasingly less viable. Consequently, we consider an architecture of autonomous decision makers. Our main contribution in this paper, denominated Generalized Autonomous Component Carrier Selection (G-ACCS), is a distributed carrier-based inter-cell interference coordination scheme that
Fourth generation (4G) data services are in the deployment stage, but is will be a few years until there is ubiquitous LTE coverage. Meanwhile, there are competitive threats emerging against incumbent carriers' core voice services. This is coming at a time when all bearer services (voice and data) are becoming marginalized due to market expectations, economic conditions, and a coming supply side expansion in terms of network capacity.This research assesses the market drivers and outlook for VoLTE as well as carrier opportunities and challenges. The report forecasts VoLTE growth for the North American region. The report includes conclusions and recommendations for network operators.