38 research outputs found
PROCESS FOR BREAKING DOWN THE LTE SIGNAL TO EXTRACT KEY INFORMATION
The increasingly important role of Long Term Evolution (LTE) has increased security concerns among the service
providers and end users and made security of the network even more indispensable. The main thrust of this thesis is to
investigate if the LTE signal can be broken down in a methodical way to obtain information that would otherwise be
private; e.g., the Global Positioning System (GPS) location of the user equipment/base station or identity (ID) of the
user. The study made use of signal simulators and software to analyze the LTE signal to develop a method to remove
noise, breakdown the LTE signal and extract desired information. From the simulation results, it was possible to
extract key information in the downlink like the Downlink Control Information (DCI), Cell-Radio Network
Temporary Identifier (C-RNTI) and physical Cell Identity (Cell-ID). This information can be modified to cause
service disruptions in the network within a reasonable amount of time and with modest computing resources.Defence Science and Technology Agency, SingaporeApproved for public release; distribution is unlimited
Heterogeneous LTE/ Wi-Fi architecture for intelligent transportation systems
Intelligent Transportation Systems (ITS) make use of advanced technologies to enhance road safety and improve traffic efficiency. It is anticipated that ITS will play a vital future role in improving traffic efficiency, safety, comfort and emissions. In order to assist the passengers to travel safely, efficiently and conveniently, several application requirements have to be met simultaneously. In addition to the delivery of regular traffic and safety information, vehicular networks have been recently required to support infotainment services. Previous vehicular network designs and architectures do not satisfy this increasing traffic demand as they are setup for either voice or data traffic, which is not suitable for the transfer of vehicular traffic. This new requirement is one of the key drivers behind the need for new mobile wireless broadband architectures and technologies. For this purpose, this thesis proposes and investigates a heterogeneous IEEE 802.11 and LTE vehicular system that supports both infotainment and ITS traffic control data. IEEE 802.11g is used for V2V communications and as an on-board access network while, LTE is used for V2I communications. A performance simulation-based study is conducted to validate the feasibility of the proposed system in an urban vehicular environment. The system performance is evaluated in terms of data loss, data rate, delay and jitter. Several simulation scenarios are performed and evaluated. In the V2I-only scenario, the delay, jitter and data drops for both ITS and video traffic are within the acceptable limits, as defined by vehicular application requirements. Although a tendency of increase in video packet drops during handover from one eNodeB to another is observed yet, the attainable data loss rate is still below the defined benchmarks. In the integrated V2V-V2I scenario, data loss in uplink ITS traffic was initially observed so, Burst communication technique is applied to prevent packet losses in the critical uplink ITS traffic. A quantitative analysis is performed to determine the number of packets per burst, the inter-packet and inter-burst intervals. It is found that a substantial improvement is achieved using a two-packet Burst, where no packets are lost in the uplink direction. The delay, jitter and data drops for both uplink and downlink ITS traffic, and video traffic are below the benchmarks of vehicular applications. Thus, the results indicate that the proposed heterogeneous system offers acceptable performance that meets the requirements of the different vehicular applications. All simulations are conducted on OPNET Network Modeler and results are subjected to a 95% confidence analysis
Auto configuration dans LTE : procédés de mesure de l’occupation du canal radio pour une utilisation optimisée du spectre
Projecte final de carrera realitzat en col.laboració amb el centre INP Grenoble - ENSIMAG. École Nationale Supérieure d’Informatique et de Mathématiques Appliquées de Grenoble i Alcatel-Lucent Bell LabsLong Term Evolution (LTE) est la quatrième génération de technologies radio qui est
conçue afin de fournir des débits de données élevés aux mobiles, offrir une faible
latence et permettre une flexibilité accrue dans l'attribution du spectre de fréquence.
Les techniques de réutilisation du spectre permettent ainsi de faire face à la demande
croissante en bande passante des utilisateurs. Nous nous concentrons sur le cas où toutes
les cellules partagent la même bande de fréquence (frequency reuse-1). Ces cellules
ainsi déployées peuvent générer des niveaux d’interférence intra-canal importants, ce
qui affecte considérablement les performances du réseau.
Le but de ce stage est de développer des méthodes de sensing du spectre permettant de
caractériser les cellules qui partagent les mêmes ressources radio. En utilisant des
informations telles que nombre de cellules en compétition notamment, les mécanismes
d’allocation des ressources radio peuvent être optimisés, améliorent ainsi la
performance du réseau.
Les méthodes ainsi étudiées exploitent les propriétés d’orthogonalité des canaux de
contrôle tels que signaux de synchronisation diffusés par chaque station de base.
Une première étape du stage a ainsi consisté à mettre en place des méthodes de
synchronisation fiables en ‘frequency reuse-1’ et d’en étudier les performances.
Au cours de la deuxième partie du stage, une méthode d’identification du nombre de
cellules en compétition sur un même canal est proposée. Cette méthode repose sur
l’utilisation des canaux de synchronisation.
Le stage a lieu sur le site de Villarceaux d’ Alcatel-Lucent Bell Labs et s’est intégré aux
projets de recherche sur l'auto-configuration des cellules dans un réseau LTE. Ce
rapport présente les travaux réalisés pendant le stage. Celui-ci s’est concentré sur la
procédure réalisée par les mobiles afin de se synchroniser au réseau. Dans cette optique,nous avons proposé une méthode pour trouver le nombre des cellules en compétition, afin de caractériser l'occupation du spectre
5G: 2020 and Beyond
The future society would be ushered in a new communication era with the emergence of 5G. 5G would be significantly different, especially, in terms of architecture and operation in comparison with the previous communication generations (4G, 3G...). This book discusses the various aspects of the architecture, operation, possible challenges, and mechanisms to overcome them. Further, it supports users? interac- tion through communication devices relying on Human Bond Communication and COmmunication-NAvigation- SENsing- SErvices (CONASENSE).Topics broadly covered in this book are; • Wireless Innovative System for Dynamically Operating Mega Communications (WISDOM)• Millimeter Waves and Spectrum Management• Cyber Security• Device to Device Communicatio
5G: 2020 and Beyond
The future society would be ushered in a new communication era with the emergence of 5G. 5G would be significantly different, especially, in terms of architecture and operation in comparison with the previous communication generations (4G, 3G...). This book discusses the various aspects of the architecture, operation, possible challenges, and mechanisms to overcome them. Further, it supports users? interac- tion through communication devices relying on Human Bond Communication and COmmunication-NAvigation- SENsing- SErvices (CONASENSE).Topics broadly covered in this book are; • Wireless Innovative System for Dynamically Operating Mega Communications (WISDOM)• Millimeter Waves and Spectrum Management• Cyber Security• Device to Device Communicatio
Estrutura hierárquica de células para transmissão MBMS
Este trabalho apresenta uma nova topologia de rede de modo a viabilizar a introdução
da nova funcionalidade MBMS (Multimedia Broadcast Multicast Service) no sistema
UMTS (Universal Mobile Telecommunication System) do futuro. Alguns dos principais
desafios referentes à implementação do MBMS prendem-se essencialmente ao nÃvel da
rede de acesso rádio, onde obstáculos como a elevada potência de transmissão,
necessária para garantir a qualidade e cobertura dos serviços, se torna num aspecto
limitativo em relação à capacidade da rede onde são esperados múltiplos e variados
serviços.
O objectivo principal deste trabalho consiste em prever e analisar a melhoria de
cobertura e throughput associada a duas novas topologias nomeadamente, Topologia
Real e Topologia de Estrutura Hierárquica de Células e tendo como referência a
Topologia Macrocelular. Para se atingir esse objectivo, teve que se implementar
(utilizando como ferramenta o JAVA) as novas topologias, onde também se utilizaram
diversas técnicas que permitem reduzir a potência de transmissão sem que isso afecte a
cobertura e o serviço recebido pelos UEs (User Equipment), nomeadamente, sistemas
MIMO (Multiple Input Multiple Output) e sistemas de Macro diversidade.
Os resultados deste trabalho provêem de um simulador ao nÃvel de Ligação (MATLAB)
interligado com um simulador RNS (Radio Network Subsystem) ao nÃvel de sistema
(JAVA).This work presents a roll of solutions to realize the introduction of the new MBMS
(Multimedia Broadcast Multicast Service) functionality in the future UMTS (Universal
Mobile Telecommunication System) network. Some of the most difficult challenges
regarding the implementation of the MBMS relies mostly at the radio access network,
where obstacles like the high transmission power necessary to guarantee the quality and
the coverage of the MBMS services makes it a limitative aspect in relation to the overall
network capacity where it is expected the transmission of multiple and diverse services.
The main objective of this work consists of predicting and analyzing the coverage and
throughput improvements associated to two new topologies namely, Real Topology and
Hierarchical Cell Structure Topology, and having the Macrocell Topology as a
reference. To reach that goal, it was necessary to implement the new topologies (using
JAVA tool), where several techniques were used to reduce the transmission power
without affecting the coverage and de service received by UEs, namely, MIMO and
Macro diversity systems.
The results of this work were based on a Link Level Simulator (MATLAB)
interconnected with a RNS (Radio Network Subsystem) System Level Simulator
(JAVA)
Terminal LTE flexÃvel
Mstrado em Engenharia Eletrónica e TelecomunicaçõesAs redes móveis estão em constante evolução. A geração atual (4G) de
redes celulares de banda larga e representada pelo standard Long Term
Evolution (LTE), definido pela 3rd Generation Partnership Project (3GPP).
Existe uma elevada procura/uso da rede LTE, com um aumento exponencial
do número de dispositivos móveis a requerer uma ligação à Internet de alto
débito. Isto pode conduzir à sobrelotação do espetro, levando a que o sinal
tenha que ser reforçado e a cobertura melhorada em locais especÃficos, tal
como em grandes conferências, festivais e eventos desportivos. Por outro
lado, seria uma vantagem importante se os utilizadores pudessem continuar
a usar os seus equipamentos e terminais em situações onde o acesso a redes
4G é inexistente, tais como a bordo de um navio, eventos esporádicos em
localizações remotas ou em cenários de catástrofe, em que as infraestruturas
que permitem as telecomunicações foram danificadas e a cobertura
temporária de rede pode ser decisiva em processos de salvamento. Assim
sendo, existe uma motivação clara por trás do desenvolvimento de uma
infraestrutura celular totalmente reconfigurável e que preencha as caracterÃsticas mencionadas anteriormente.
Uma possÃvel abordagem consiste numa plataforma de rádio definido por
software (SDR), de código aberto, que implementa o standard LTE e corre
em processadores de uso geral (GPPs), tornando possÃvel construir uma rede
completa investindo somente em hardware - computadores e front-ends de
radiofrequência (RF). Após comparação e análise de várias plataformas LTE
de código aberto foi selecionado o OpenAirInterface (OAI) da EURECOM,
que disponibiliza uma implementação compatÃvel com a Release 8.6 da
3GPP (com parte das funcionalidades da Release 10).
O principal objectivo desta dissertação é a implementação de um User
Equipment (UE) flexÃvel, usando plataformas SDR de código aberto que corram
num computador de placa única (SBC) compacto e de baixa potência,
integrado com um front-end de RF - Universal Software Radio Peripheral
(USRP). A transmissão de dados em tempo real usando os modos de duplexagem
Time Division Duplex (TDD) e Frequency Division Duplex (FDD) é suportada e a reconfiguração de certos parâmetros é permitida, nomeadamente
a frequência portadora, a largura de banda e o número de Resource
Blocks (RBs) usados. Além disso, é possÃvel partilhar os dados móveis LTE
com utilizadores que estejam próximos, semelhante ao que acontece com
um hotspot de Wi-Fi. O processo de implementação é descrito, incluindo
todos os passos necessários para o seu desenvolvimento, englobando o port
do UE de um computador para um SBC. Finalmente, a performance da rede
é analisada, discutindo os valores de débitos obtidos.Mobile networks are constantly evolving. 4G is the current generation of
broadband cellular network technology and is represented by the Long Term
Evolution (LTE) standard, de ned by 3rd Generation Partnership Project
(3GPP). There's a high demand for LTE at the moment, with the number
of mobile devices requiring an high-speed Internet connection increasing exponentially.
This may overcrowd the spectrum on the existing deployments
and the signal needs to be reinforced and coverage improved in speci c sites,
such as large conferences, festivals and sport events. On the other hand,
it would be an important advantage if users could continue to use their
equipment and terminals in situations where cellular networks aren't usually
available, such as on board of a cruise ship, sporadic events in remote
locations, or in catastrophe scenarios in which the telecommunication infrastructure
was damaged and the rapid deployment of a temporary network
can save lives. In all of these situations, the availability of
exible and easily
deployable cellular base stations and user terminals operating on standard
or custom bands would be very desirable. Thus, there is a clear motivation
for the development of a fully recon gurable cellular infrastructure solution
that ful lls these requirements.
A possible approach is an open-source, low-cost and low maintenance
Software-De ned Radio (SDR) software platform that implements the LTE
standard and runs on General Purpose Processors (GPPs), making it possible
to build an entire network while only spending money on the hardware
itself - computers and Radio-Frequency (RF) front-ends. After comparison
and analysis of several open-source LTE SDR platforms, the EURECOM's
OpenAirInterface (OAI) was chosen, providing a 3GPP standard-compliant
implementation of Release 8.6 (with a subset of Release 10 functionalities).
The main goal of this dissertation is the implementation of a
exible opensource
LTE User Equipment (UE) software radio platform on a compact
and low-power Single Board Computer (SBC) device, integrated with an
RF hardware front-end - Universal Software Radio Peripheral (USRP). It
supports real-time Time Division Duplex (TDD) and Frequency Division
Duplex (FDD) LTE modes and the recon guration of several parameters,
namely the carrier frequency, bandwidth and the number of LTE Resource
Blocks (RB) used. It can also share its LTE mobile data with nearby users,
similarly to a Wi-Fi hotspot. The implementation is described through
its several developing steps, including the porting of the UE from a regular
computer to a SBC. The performance of the network is then analysed based
on measured results of throughput