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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Harnessing 5G for Public Safety and Health : Challenges and Investment Areas

Othman, Taha, Karagiannis, Ioannis January 2021 (has links)
The introduction of 5G technology in combination with smart cities will revolutionize the world economically and from the quality of life point of view. Different sectors will be impacted by this revolution such as (1) public health and safety, (2) mobility and transportation and (3) energy and water. This thesis will focus on Public Health and Safety. The characteristics that affect or boost the Return on Investment of 5G investments will be analyzed and a business model for the proper implementation of such investments will be presented. We will use the regression analysis to study the characteristics that affect the Return on Investment using 5G in Public Health and Safety. We will also use the VISOR model to define a business model for one of the services in Public Health and Safety namely the infectious disease surveillance. Our goal is to study this field of industry dynamics, technology and innovation and provide a holistic view from selecting the service up to identifying the business model.
2

Algoritmy synchronizace pro systémy 5G v pásmu milimetrových vln / Synchronization methods for millimeter-wave 5G systems

Waldecker, Miroslav January 2018 (has links)
Goal of this thesis is to analyse basic algorithms for the carrier and time synchronisation in the OFDM systems in 5G networks. Firtly, basic introduction to OFDM systems, then parameters and properties of the OFDM are discussed. Then estimation and compensation timing and frequency offsets are analysed as well as algorythms for searhcing of the start of the symbols. Last but not least hardware setup, which will be prepared in the DREL department for test of the communication in the millimeter wave band, with frequency of 60GHz is slightly discribed. This thesis is just a introduction for the real future work on this setup.
3

Algoritmy synchronizace pro systémy 5G v pásmu milimetrových vln / Synchronization methods for millimeter-wave 5G systems

Waldecker, Miroslav January 2018 (has links)
Goal of this thesis is to analyse basic algorithms for the carrier and time synchronisation in the OFDM systems in 5G networks. Firtly, basic introduction to OFDM systems, then parameters and properties of the OFDM are discussed. Then estimation and compensation timing and frequency offsets are analysed as well as algorythms for searhcing of the start of the symbols. Last but not least hardware setup, which will be prepared in the DREL department for test of the communication in the millimeter wave band, with frequency of 60GHz is slightly discribed. This thesis is just a introduction for the real future work on this setup.
4

Machine Learning Enabled-Localization in 5G and LTE Using Image Classification and Deep Learning

Mukhtar, Hind 23 July 2021 (has links)
Demand for localization has been growing due to the increase in location-based services and high bandwidth applications requiring precise localization of users to improve resource management and beam forming. Outdoor localization has been traditionally done through Global Positioning System (GPS), however it’s performance degrades in urban settings due to obstruction and multi-path effects, creating the need for better localization techniques. This thesis proposes a technique using a cascaded approach composed of image classification and deep learning using LIDAR or satellite images and Channel State In-formation (CSI) data from base stations to predict the location of moving vehicles and users outdoors. The algorithm’s performance is assessed using 3 different datasets. The first two use simulated data in the Milli-meter Wave (mmWave) band and lidar images that are collected from the neighbourhood of Rosslyn in Arlington, Virginia. The results show an improvement in localization accuracy as a result of the hierarchical architecture, with a Mean Absolute Error (MAE) of 6.55m for the proposed technique in comparison to a MAE of 9.82m using one Convolutional Neural Network (CNN). The third dataset uses measurements from an LTE mobile communication system along with satellite images that take place at the University of Denmark. The results achieve a MAE of 9.45 m fort he heirchichal approach in comparison to a MAE of 15.74 m for one Feed-Forward Neural Network (FFNN).
5

Étude et conception d'antennes multifaisceaux en bandes V et E pour les futurs réseaux cellulaires hétérogènes 5G / Design and development of multibeam antennas in V- and E-bands for future cellular networks 5G

Potelon, Thomas 19 December 2017 (has links)
L'évolution des technologies numériques a permis l'introduction d'objets connectés dans le quotidien d'une grande partie de la population mondiale. Face à une demande de données sans-fil toujours croissante, des techniques nouvelles doivent être employées pour offrir un débit plus élevé à des appareils moins volumineux et accessibles à un prix raisonnable. Les antennes constituent l'organe central de toutes les télécommunications et elles jouent un rôle majeur dans l'évolution vers des systèmes plus performants. En effet, l'augmentation du débit de données passe par une augmentation du gain et de la bande de fonctionnement, et plus une antenne est directive plus son intégration est complexe. La tendance actuelle est à l'évolution vers les bandes de fréquences millimétriques, ce qui permet une réduction du volume de l'antenne et l'utilisation de bandes de fréquences plus larges, néanmoins la fabrication est un vrai défi technologique. Les travaux de recherches effectués au cours de cette thèse portent sur la conception d'antennes pour une application de lien backhaul : une liaison en bande E (71-86GHz) entre deux antennes fixes utilisée dans un réseau cellulaire ; cependant les concepts et technologies sont facilement transposables à d'autres applications telles que les radars ou les communications satellitaires. Les systèmes étudiés combinent un réseau unidimensionnel de longues fentes rayonnantes (CTS) alimentées en parallèles avec un formateur de faisceau quasi-optique (système pillbox). Les fentes rayonnantes consistent en guides à plans parallèles (GPP) tronqués. Elles sont alimentées en parallèle par un réseau de division de puissance exclusivement basé sur des GPP. Le système pillbox est constitué de deux GPP connectés par un coupleur et un réflecteur parabolique intégré, l'illumination de ce dernier par une source focale génère une onde plane. L'omniprésence de GPP au sein de l'antenne garantit une large bande de fonctionnement, et l'architecture employée permet une meilleure intégration que les antennes quasi-optiques. Ces antennes offrent donc un compromis entre un gain élevé, une large bande de fonctionnement et un profile réduit qui ne peut pas être atteint avec les autres structures présentes dans la littérature. Malheureusement ces antennes comportent également des désavantages. D'un point de vue technologique, leur fabrication est complexe et coûteuse. C'est pourquoi dans ces travaux de thèse un intérêt particulier est porté sur l'utilisation de techniques nouvelles permettant la fabrication de prototypes menant à des résultats expérimentaux. Du point de vue des performances en rayonnement, les antennes CTS/pillbox actuelles ne permettent pas de reconfigurer le rayonnement dans le plan E et le niveau de recouvrement dans le plan H est trop faible pour pouvoir être facilement exploité. Dans cette thèse, des solutions innovantes sont proposées afin de remédier à ce manque de versatilité. Enfin jusqu'à présent, le niveau des lobes secondaires dans le plan E de l'ensemble des antennes CTS alimentées en parallèle est d'environ -13,5dB. Une structure nouvelle est introduite afin de permettre une réduction de ces lobes secondaires à un niveau très faible. / The evolution of numerical technologies allowed the daily use of connected object for a large part of the world’s population. To fulfill the ever-growing demand for wireless communication, new technologies have to be developed in order to obtain higher data-rate with smaller and cheaper devices. The antenna plays a major role in communication systems and their performances are to be improved to obtain more efficient telecommunications. Indeed the rise of data-rate involves an improvement of the antenna gain and bandwidth, but the integration of directive antennas is always challenging. The actual trend is the shift to higher frequency bands, in the millimeter-wave range, this allows a size reduction together with the use of broader bandwidth; however the fabrication becomes a real challenge. The research work realized in this thesis concern the design, fabrication and experimental characterization of antennas for backhaul links: the E-band (71-86GHz) communication between two fixed antennas used in cellular network; nonetheless the solutions developed can easily be applied to other applications such as radar or satellite communications.The studied systems combine a one-dimensional array of long radiating slots (CTS) fed in parallel with a quasi-optical beam forming network (pillbox system). The radiating slots are made of truncated parallel plate waveguides (PPW) and are fed in parallel by a power-divider network realized in PPW technology. The pillbox system consists of two stacked PPWs connected by a multi-slot coupler and an integrated parabolic reflector, the latter converts the cylindrical wave emitted by a focal feed into a planar wave. The omnipresence of PPWs throughout the antenna system insures a broad band of operation, and the architecture shows a lower profile than quasi-optical antennas. This antenna presents an unequaled tradeoff between a high gain, a wide bandwidth and a low-profile. Unfortunately they also have drawbacks. From a technological point of view, their fabrication is complicated and expensive. This is why in this thesis a particular attention is given to the use of new techniques allowing the fabrication of prototypes leading to experimental validation of the results. From the radiation performance point of view, CTS/pillbox antennas do not show any reconfigurability solution in the E-plane and the overlap level obtained in H-plane with already existing antennas is too low to be usable. In this thesis, innovative solutions are investigated to find solution to this lake of versatility. Finally the sidelobe level (SLL) in E-plane of the totality of parallel-fed CTS antennas described in the open-literature is about -13.5dB. A new architecture introduced in this thesis allows a reduction of this SLL down to a negligible level.
6

Harmonic feedback multi-oscillator for 5G application / Un oscillateur harmonique pour l'application 5G

Mohsen, Ali 13 December 2018 (has links)
Le projet de thèse porte sur l'oscillateur harmonique; l'oscillateur dépend du signal de fréquence fondamentale à 25 GHz, qui est amplifié à l'aide d'un LNA et d'un amplificateur de puissance afin de générer un troisième signal harmonique à 75 GHz en sortie et de faire une contre-réaction du signal fondamental afin d'assurer la continuité de l'oscillation. Un diplexeur est utilisé pour séparer les deux fréquences à l’étage de sortie, en tenant compte de l’amélioration de la puissance de sortie, du bruit de phase et de l’efficacité de puissance ajoutée PAE à la fréquence candidate de l’application 5G. La technologie de transistor choisie est le FDSOI 28 nm de STMicroelectronics. / The PhD project is about harmonic oscillator; the oscillator depends on the fundamental frequency signal at 25 GHz which is amplified using an LNA and power amplifier in order to generate third harmonic signal at 75 GHz at the output, and feedback the fundamental signal to ensure the continuity of the oscillation. A diplexer is used to separate between both frequencies at the output stage, taking in consideration the improvement of the output power, phase noise, and the power added efficiency PAE at the candidate frequency of 5G application. The transistor technology chosen is the 28nm FDSOI from the STMicroelectronics.
7

Recent advances in antenna design for 5G heterogeneous networks

Elfergani, Issa T., Hussaini, A.S., Rodriguez, J., Abd-Alhameed, Raed 14 January 2022 (has links)
Yes
8

Outdoor to Indoor Coverage in 5G Networks

Rydén, Vilhelm January 2016 (has links)
Outdoor to indoor mobile coverage is evaluated for differentfrequencies in two scenarios, a single building scenario and a cityenvironment. A new model for outdoor to indoor propagation issuggested, connecting existing, highly detailed indoor and outdoorray-tracing propagation models. The model is compared to previous,site specific as well as statistical, propagation models. Resultsconclude that the new model gives higher path gain for edge users inthe single building scenario, whereas results from the city scenarioare inconclusive. Furthermore, results from the single buildingscenario suggest that indoor coverage is possible at 5 GHz and belowfor most buildings, whereas for the city scenario indoor coverage at5 GHz will be possible only for buildings without metally coatedwindows. Achieving indoor coverage at 30 GHz is highly problematicfor all cases, and it is concluded that indoor base stations arenecessary if frequencies of 10 GHz and above are to be used infuture mobile networks. In addition, an indoor analysis is made to verify existing lossper meter indoor models. It is concluded that such models are oftenoptimistic, although their assumption of log-normal shadowing remainvalid, at least for closed offices. Furthermore, the assumption ofloss as a linear function of distance might be unfeasible for higherfrequencies, where a breakpoint in the linear model was observed ata distance of roughly 10 meters.
9

Novel Approach for Designing Dual-Band 5G Antenna Integrated Reflector

Faridani, Mohammad 14 April 2023 (has links)
As the world continues to adopt the next generation of mobile technology, dual-band 5G wireless communications are becoming increasingly significant. 5G technology operates on two different frequency bands, the sub-6 GHz Frequency Range (FR1) and the millimeter wave (MMW) Frequency Range (FR2). The special features in each band enable 5G dual-band communication to provide better coverage and capacity than previous generations of wireless networks. This is especially essential for applications that need high-bandwidth and low-latency connections, such as virtual and augmented reality, autonomous vehicles, and industrial automation. Furthermore, dual-band 5G can help alleviate network congestion in urban areas by redirecting traffic to the MMW band, which has considerably greater capacity. As a result, dual-band 5G is expected to play a critical role in facilitating the next wave of technological innovation and revolutionizing the way we live and work. A dual-band antenna with a large frequency ratio (FR) is required due to the significant difference between each frequency band in 5G. Research on dual-band antennas is facing challenges such as low FR and a lack of a specific design methodology. Despite attempts to develop dual-band antennas with large FRs, there are still issues with low performance and limited bandwidth. This study introduces a novel approach for designing a dual-band antenna with a large FR. The proposed solution draws inspiration from a hybrid design of a dual-band antenna to achieve a large FR, and from the parabolic reflector antenna design to significantly enhance gain in the upper band. The lower band antenna in this design serves as both a radiator for the lower band and a reflector to align the beam in the upper band. This approach can be used to design dual-band antennas for various frequencies. In this thesis, we present a comprehensive model and framework for designing an antenna integrated reflector that offers a large FR. The proposed model is capable of producing an antenna that meets the requirements of the targeted application, namely 5G. This antenna exhibits wideband characteristics and high gain. Two different antenna integrated reflectors, named AIR-I and AIR-II, were designed based on the proposed model. AIR-I has a FR of 10.1. As for AIR-II, due to the presence of dual-band upper antennas, it has a lower band at 1.35 GHz and two upper bands at 13 GHz and 24 GHz thus, a FR of 9.5 and 18, respectively. The above design followed a specific purpose. It uses a 24 GHz/1.35 GHz frequency ratio of 18 to showcase the antenna performance in the context of dual-band 5G. However, the measurement facilities being limited to 20 GHz, a frequency ratio of 9.5 at 13 GHz/1.35 GHz was measured for the AIR-II, as proof of concept. Then, two prototypes were fabricated from AIR-II namely, Prototype-I and Prototype-II. While it would have been possible to demonstrate a proof of concept from a single prototype, it has been decided to produce and test two samples to enable a more exhaustive examination of the subject and obtain additional data that would lend greater support to the model outlined in this thesis. Prototype-I had the same structure as AIR-II and had an operational bandwidth of 0.69 GHz-1.74 GHz / 6 GHz-18 GHz and a FR of 9.9. On the other hand, Prototype-II had an operational bandwidth of 0.69 GHz-1.74 GHz / 13 GHz-18 GHz and a FR of 12.8. These prototypes exhibited maximum bandwidths of 100% and 86%, respectively. Furthermore, at the upper band, Prototype-I achieved a peak gain improvement of 12.6 dB, while Prototype-II achieved an improvement of 8.7 dB. These results demonstrated the significant advantages of our proposed methodology in dual-band antenna design.
10

An ML-based Method for Efficient Network Utilization in Online Gaming Using 5G Network Slicing

Saleh, Peyman 18 July 2023 (has links)
Online video gaming has become a ubiquitous aspect of modern-day video gaming. It has gained immense popularity due to its accessibility and immersive experience, resulting in millions of players worldwide participating in various online games. Depending on the type of gameplay, the players’ quality of experience (QoE) in online video gaming can be significantly affected by network factors such as high bandwidth and low latency. As such, providers of online gaming services are competing to offer the highest quality of experience to their users at reasonable prices. To achieve this objective, online game providers face two main challenges. Firstly, they must accurately estimate the network throughput capacity required to meet the servers’ demands and ensure that the QoE is not compromised. Secondly, they must be able to secure the required throughput with network providers, which, in the current conventional network infrastructure, is neither agile nor dynamic. Thus, online game providers have to prepay for extra network throughput capacity or choose a cost-effective capacity that may result in potential QoE losses during peak usage. To address these challenges, this thesis proposes a deep neural network-based model that utilizes a QoE-aware loss function for predicting the future network throughput de- mand. The model can accurately estimate the network throughput capacity required to maintain QoE levels while minimizing the cost of network resources. By doing so, on- line game providers can achieve optimal network resource allocation and effectively meet servers’ demands. Furthermore, this thesis proposes a slice optimizer module that employs 5G network slicing and a machine learning model to optimize network slices in a cost-efficient manner that satisfies both the online game provider’s and the network provider’s requirements. This module can dynamically allocate network resources based on the game provider’s QoE requirements, the network provider’s resource availability, and the cost of network resources. As a result, online game providers can efficiently manage network resources, optimize network slicing, and effectively control the cost of network resources.

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