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Still providing the thorough breakdown of the key areas of LTE of the first edition, this new revised edition of LTE for UMTS includes some important new sections on updates to the standards, as well as a look at possible future developments"--Provided by publisher.

LTE/LTE-A are emerging communication technologies on the way towards 5G telecommunication systems. Ubiquitous adoption of connectivity in between different kinds of sensors, wearable devices and other low-power equipment raises an importance of the energy-efficient wireless communications. In LTE/LTE-A the Discontinuous Reception Mechanism (DRX) aims at power saving of User Equipment (UE) devices. In the paper we present an analysis of DRX, which is novel in two dimensions. First, our analytical approach is different to existing ones due to the use of Markov chain instead of a semi-Markov ones. Secondly, along with the generic traffic models we also analyze the efficiency of DRX for military training application systems, what has not been done before. We suggest few practical recommendations regarding the DRX parameters tuning also. © 2015 IEEE.

Military communication systems are nowadays improving slowly compared to commercial systems. In parallel, public safety (ps) communication systems are changing due to emergence of long term evolution (LTE) as a mature solution. However, LTE is initially designed for commercial cellular network and need to be evolved to tackle the requirements of ps use cases. In this thesis, we develop a complete solution to address constrained ps and military use-cases allowing to wirelessly mesh mobile network nodes and to provide access to standard user equipments while only requiring a single radio band. Starting from ps and military use cases, we present the potential scenarios and derive functional requirements for future wireless systems. The constraints applying to these systems lead to the selection of LTE as the radio access technology. We detail the challenges faced by a LTE solution given the state of the art. We present a novel network infrastructure architecture that enables multi-hop LTE mesh networking for autonomous base stations via in-band self-backhauling relying on a new base station: the e2nb. We detail the building blocks of the architecture, we investigate the coordination and orchestration functionality and propose a cross layer hierarchical resource scheduling algorithm in order to efficiently meet quality of service requirements for real-time traffic while maximizing the throughput for elastic flows. We evaluate the self-backhauling interface using open air interface and then evaluate our resource scheduling algorithm in various network topologies and traffic flows. Finally, we summarize the remaining uncertainties concerning real-field deployments. ; Les systèmes de communication militaires s'améliorent aujourd'hui lentement comparés aux systèmes civils. les systèmes de communications pour les réseaux de sécurité publique évoluent suite à l'émergence de la technologie long term evolution (LTE). Cependant, le LTE a initialement été conçu pour les réseaux cellulaires commerciaux. Dans cette thèse, nous ...

PUBLISHED ; As early as 2014, mobile network operators? spectral capacity will be overwhelmed by the demand brought on by new devices and applications. To augment capacity and meet this demand, operators may choose to deploy a Dynamic Spectrum Access (DSA) overlay. The signaling and functionality required by such an overlay have not yet been fully considered in the architecture of the planned Long Term Evolution Advanced (LTE+) networks. This paper presents a Spectrum Accountability framework to be integrated into LTE+ architectures, defining specific element functionality, protocol interfaces, and signaling flow diagrams required to enforce the rights and responsibilities of primary and secondary users. We also quantify, through integer programs, the benefits of using DSA channels to augment capacity under a scenario in which the LTE+ network can opportunistically use TV and GSM spectra. The framework proposed here may serve as a guide in the development of future LTE+ network standards that account for DSA ; This work was supported by the Idaho National Laboratory (INL) Ph.D. Candidate Program and Virginia Tech Bradley Fellowship. Work supported through the INL is supported through the Laboratory Directed Research & Development (LDRD) Program under DOE Idaho Operations Office Contract DE-AC07-05ID14517. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Department of Energy or the U.S. Government

Abstract
In the paper solutions of trunking-dispatch systems based on the LTE system are presented. The solution in the form of separate LTE/TDD trunking system is discussed, and the concept of the LTE/FDD trunking system operating in the infrastructure of public, mobile networks is characterised.

The 3GPP has raised the need to revisit the design of next generations of cellular networks in order to make them capable and efficient to provide M2M services. One of the key challenges that has been identified is the need to enhance the operation of the random access channel of LTE and LTE-A. The current mechanism to request access to the system is known to suffer from congestion and overloading in the presence of a huge number of devices. For this reason, different research groups around the globe are working towards the design of more efficient ways of managing the access to these networks in such circumstances. This paper aims to provide a survey of the alternatives that have been proposed over the last years to improve the operation of the random access channel of LTE and LTE-A. A comprehensive discussion of the different alternatives is provided, identifying strengths and weaknesses of each one of them, while drawing future trends to steer the efforts over the same shooting line. In addition, while existing literature has been focused on the performance in terms of delay, the energy efficiency of the access mechanism of LTE will play a key role in the deployment of M2M networks. For this reason, a comprehensive performance evaluation of the energy efficiency of the random access mechanism of LTE is provided in this paper. The aim of this computer-based simulation study is to set a baseline performance upon which new and more energy-efficient mechanisms can be designed in the near future. ; Grant number : This work has been funded by the Catalan Government under grant 2009-SGR-940, research projects CO2GREEN (TEC2010-20823).© 2014 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

ns-3 is an open-source network simulator with support for simulating 3GPP LTE cellular network. This paper presents three extensions to the LTE module of ns-3, enhancing its capability of simulating scenarios with more sophisticated user mobility requirements. The first extension implements additional features in the UE measurements function. The second extension delivers additional handover algorithms and a modular framework for ns-3 users to incorporate their own handover algorithms. At last, the third extension enables automatic network attachment using the initial cell selection procedure. The modelling of these extensions refers to 3GPP standard specifications. The resulting models have been validated using the ns-3 testing framework. ; Grant numbers : The work presented in this paper was generously funded by the Google Summer of Code 2013 programme. The work done at the Centre Tecnològic de Telecomunicacions de Catalunya was also partially funded by the Spanish Ministry of Science and Innovation through the project SYMBIOSIS (TEC2011-29700-C02-01) and by the Catalan Regional Government under grant 2009SGR-940.

Wireless network virtualization enables efficient network sharing in Long Term Evolution Advanced (LTE-A) networks. For the accommodation of ever-increasing user demands, Mobile Virtual Network Operators (MVNOs) can lease and operate virtual resources in network infrastructure that belongs to Mobile Network Operators (MNOs). The coexistence of multiple MVNOs that serve users with different Quality of Service (QoS) requirements and spatial distribution in an LTE-A cell further complicates the arising resource allocation problem. Moreover, the MVNOs aim to satisfy the QoS demands for the maximum possible number of users with the minimum possible cost. This multifaceted context renders centralized optimization approaches for virtual resource allocation in shared LTE-A networks unsuitable. As an alternative, the framework of matching theory, thanks to its distributed nature, can achieve a proper allocation through a stable matching between resources and MVNOs. In this context, we introduce a matching-theoretic formulation for the virtual resource allocation problem and propose a distributed algorithm that properly matches the MVNOs with the available resources. Our simulation results show that the proposed algorithm reaches a stable matching that satisfies the QoS demands for more users in comparison with other approaches. ; Grant numbers : This work has been funded by the Research Project CellFive (TEC2014-60130-P), AGAUR the Catalan Government (2014-SGR-1551).© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.