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EnergyBox: Tool improvement and GUIPolis, Rihards January 2014 (has links)
EnergyBox is a parametrised estimation tool that uses packet traces as input to simulate the energy consumption of communication in mobile devices. This tool models the transmission behaviour of a smart phone by analysing a recorded packet trace from the device. The purpose of the thesis is to reimplement the original EnergyBox energy consumption modelling tool. The project aims to develop support for a graphical user interface (GUI) and a code base that is easier to modify and maintain. The motivation for the reimplementation of the tool is to simplify its usage and to structure the code so that new features can be added. The existing features such as the calculation of total power consumed by the packet trace and the modelling of a device's energy states are reimplemented and new features are developed. Among the new features, a GUI is added to simplify the usage of the application features such as the detection of the recording device's IP address and the ability to alter the configuration parameters used as input to the energy model. The application is written with a GUI and modularity in mind. This is achieved using Java's proprietary new GUI framework - JavaFX, which supports built-in chart and graph GUI elements, that can be easily integrated and supported. The energy modelling engines follow the semantics of the original implementation and the evaluation shows that the new implementation's results are identical to the original tool in 94.94% of the tested cases.
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Cross-layer techniques for Wireless Local Area Networks / Approche inter-couches dans les réseaux sans filBerezin, Maria Eugenia 19 December 2013 (has links)
Dans cette thèse, nous examinons les aspects essentiels des réseaux locaux sans fil IEEE 802.11 (réseaux WiFi) en mode infrastructure, et identifions les problèmes qui peuvent affecter leurs performances. Après avoir étudié l'état de l'art, nous constatons que de nombreux efforts de recherche ont proposé des solutions diverses mais présentant des limitations qui empêchent leur déploiement dans les réseaux locaux sans fil existants. En outre, les utilisateurs de ces réseaux ont des attentes toujours croissantes de disponibilité, de fiabilité, de réponse instantanée et de sécurité de la part de leurs connexions sans fil. Motivés par ces défis, nous concevons et mettons en œuvre des solutions nouvelles et concrètes aux problèmes ouverts liés à la performance des réseaux locaux sans fil IEEE 802.11. Nous adoptons une approche centrée sur le point d'accès (Access Point), qui n'introduit pas de modifications côté client. Nous nous concentrons sur les aspects suivants des réseaux locaux sans fil : la mobilité des clients, la gestion des canaux, et la qualité de service, et nous explorons trois différents scénarios pour les déploiements les plus répandus : une entreprise, une ville (zone urbaine), et une résidence personnelle (maison ou appartement). Afin de fournir une base commune pour la mise en œuvre pratique de nouvelles solutions 802.11, nous introduisons un modèle de point d'accès intelligent, inspiré des techniques d'auto-gestion. Les contributions principales de cette thèse sont les suivantes : 1. Nous développons une solution de mobilité transparente pour la Voix sur IP (VoIP) dans les réseaux sans fil d'entreprise, appelée Multichannel Virtual Access Point (mVAP), qui n'introduit aucune modification côté client et reste compatible avec les appareils actuels. Nous mettons en œuvre et évaluons mVAP en utilisant du matériel 802.11 standard, et accomplissons une mobilité transparente sans interruption ni dégradation des communications en cours. 2. Nous étudions la possibilité d'exploiter la couverture WiFi existante dans les zones urbaines pour obtenir un accès mobile à Internet, grâce à des simulations réalisées à partir de données réelles collectées par des téléphones portables. Les résultats montrent que cette couverture WiFi est large et que la connectivité offerte peut être efficacement utilisée. Nous identifions des questions ouvertes concernant le déploiement effectif d'un tel réseau WiFi à l'échelle d'une ville, et les applications qui pourraient en bénéficier. 3. Nous proposons un mécanisme dynamique de sélection de canal pour les réseaux locaux sans fil personnels (maisons et appartements), qui utilise la charge de trafic variable dans le temps pour l'estimation d'interférences. Nous mettons en œuvre cette solution en utilisant du matériel 802.11 standard, et nous l'évaluons expérimentalement : les performances d'un tel réseau sont considérablement améliorées en choisissant le canal qui présente le moins d'interférences. / In this dissertation, we examine important aspects of infrastructure IEEE 802.11 Wireless Local Area Networks (WLANs) and identify issues that can affect their performance. Reviewing the state of the art, we observe that numerous research efforts have proposed diverse solutions with several limitations that impede their deployment in existing WLANs. Moreover, users have ever-increasing expectations of availability, reliability, instantaneous response and security from their wireless connections. Motivated by these challenges, we design and implement novel but practical solutions that address open issues affecting the performance of IEEE 802.11 WLANs. We adopt an Access Point (AP)-based approach, which does not require any modification in the clients. We focus on the following aspects of WLANs: client mobility, channel management, and quality of service, and explore three different scenarios for the most common deployments: an enterprise, a city (urban area), and a personal residence (home). To provide a common basis for practical implementation of new 802.11 solutions, we present a Smart AP model, inspired by self-management techniques. The main contributions of this thesis are: 1. We develop a seamless mobility solution for Voice over IP (VoIP) services in Enterprise WLANs, called Multichannel Virtual Access Points (mVAP), which requires no client modifications and is compatible with current devices. We implement and evaluate mVAP using commodity 802.11 hardware, and achieve transparent mobility without interruption or degradation of ongoing communications. 2. We investigate the feasibility of harnessing the existing WiFi coverage in urban areas for mobile Internet access, through trace-based simulations using real data collected by mobile phones. The results show that the WiFi coverage is large and the connectivity it offers can be effectively exploited. We identify open issues for the actual deployment of such a citywide WiFi network and the applications that could benefit from it. 3. We propose an adaptive traffic-aware channel selection mechanism for Home WLANs, that uses the time-varying traffic load for interference estimation. We implement this solution using commodity 802.11 hardware and experimentally evaluate it: the network performance is drastically improved by constantly picking the channel with the least interference.
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Airbourne WiFi Networks Through Directional Antenna: An Experimental StudyGu, Yixin 05 1900 (has links)
In situations where information infrastructure is destroyed or not available, on-demand information infrastructure is pivotal for the success of rescue missions. In this paper, a drone-carried on demand information infrastructure for long-distance WiFi transmission system is developed. It can be used in the areas including emergency response, public event, and battlefield. The WiFi network can be connected to the Internet to extend WiFi access to areas where WiFi and other Internet infrastructures are not available. In order to establish a local area network to propagate WIFI service, directional antennas and wireless routers are used to create it. Due to unstable working condition on the flying drones, a precise heading turning stage is designed to maintain the two directional antennas facing to each other. Even if external interferences change the heading of the drones, the stages will automatically rotate back to where it should be to offset the bias. Also, to maintain the same flying altitude, a ground controller is designed to measure the height of the drones so that the directional antennas can communicate to each other successfully. To verify the design of the whole system, quite a few field experiments were performed. Experiments results indicates the design is reliable, viable and successful. Especially at disaster areas, it’ll help people a lot.
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Exploring the Advantages, Disadvantages, and Challenges of Implementing a Hybrid LiFi and WiFi Network : A Systematic Literature ReviewIngemarsson, Jonas January 2023 (has links)
I takt med att efterfrågan på trådlös kommunikation med hög hastighet ökar och det ökande antalet enheter som är trådlöst anslutna har forskare börjat utforska kompletterande teknologier. Hybridnätverk bestående av LiFi och WiFi är en kombination av Light-Fidelity och Wireless-Fidelity som kombinerar dataöverföring över både radiovågor och ljus. Hybridnätverk med LiFioch WiFi är ett lovande system där hastigheter över 10 Gbps är möjliga och teknikerna inte kan störa ut varandra. Den systematiska litteraturstudie som genomförts syftade till att kartlägga fördelar, nackdelar och utmaningar vid implementationen av dessa hybridnätverk. Sökningar efter litteratur för studien gjordes i fem olika databaser med hjälp av en specifik sökterm, vilket resulterade i 43 accepterade artiklar. En kvalitativ metod, tematisk kodning, användes för att hitta svaren, vilket resulterade i att 20 subteman identifierades spridda över de tre olika huvudteman. Analysen visade att den mest frekvent rapporterade fördelen var prestanda, den vanligaste nackdelen var handover och den mest framträdande utmaningen var load balancing. / With the increasing demand for high-speed wireless communication and the growing numberof devices connected wirelessly, researchers have started exploring complementary technologies. Hybrid LiFi and WiFi networks are a combination of Light-Fidelity and Wireless-Fidelity, which combine data transmission over Radio Frequency and light. Hybrid LiFi and WiFi networks are a promising system that offers speeds above 10 Gbps without interference from one another. The conducted systematic literature review aimed to discover the advantages, disadvantages, and challenges of implementing a hybrid LiFi and WiFi network. The search for literature was conducted in five different databases using one search term, resulting in 43 accepted articles. A qualitative approach using thematic coding was conducted to find the answers, resulting in 20 sub-themes divided over the three main themes. The analysis showed that the most frequently reported advantage was performance, the most common disadvantage was handover, and the most appearing challenge was load balancing.
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Geotracking : En parameter för morgondagens hyror? / Geotracking : A parameter for tomorrow’s rent?Nylander, Oskar, Ryott Hööglund, Victor January 2017 (has links)
Handeln i fysiska butiker står inför en stor utmaning, konkurrensen från e-handeln tar marknadsandelar. Detta innebär ett problem för butiksinnehavare och därmed även för fastighetsägare. Många är idag överens om att handeln i fysiska butiker kommer att behöva genomgå stora förändringar för att fortsätta attrahera kunder. Många butiker blir idag mer som showrooms där människor testar varor som sedan handlas online. När detta sker så skiftar butikens syfte från försäljning till att vara en marknadsföringskanal för varumärket. Idag bestäms butikshyran till ett fast belopp eller baseras på omsättning men om butiken blir en marknadsföringsplats kan det vara mer relevant att ta betalt baserat på hur många som ser butiken. Med hjälp av en ny teknik vid namn geotracking kan man ta fram noggrann data på hur många personer som passerar utanför en butik. Geotracking är ett samlingsbegrepp för olika tillvägagångssätt att spåra människors geografiska position genom deras mobiltelefoner. Det går ut på att man på olika sätt mäter radiovågor som telefonerna sänder ut. Syftet med denna rapport är att undersöka om man kan använda geotracking som underlag för hyressättning av butikslokaler. För att besvara detta har rapporten delats in efter tre, för geotracking, grundläggande förutsättningar. Dessa är teknik, hyressättning och integritet. Resultatet av studien visar att det finns ett behov av att optimera hyressättningen av butiker för att möta framtida utmaningar. Den visar också att de tre grundförutsättningarna för geotracking går att uppfylla varför det är lämpligt att använda geotracking vid hyressättning av butikslokaler. / The Retail industry is facing a big challenge, competition from e-commerce that is taking market shares. This poses a problem for shopkeepers and therefore also for property owners. Today various people agree that the retail industry will need to undergo major changes to keep attracting customers. Many stores today become more like showrooms where people test products that are then bought online. When this happens, the shop's purpose changes from sales to being more like marketing for the brand. Today, a stores rent is determined at a fixed amount or based on sales, but if the store becomes a marketing site, it may be more relevant to charge based on how many people see the store. Using a new technique called geotracking, you can get accurate data on how many people pass outside a store. Geotracking is a collective term for different approaches to trace people's geographic position through their mobile phones. It works by measuring radio waves as the phones broadcast. The purpose of this report is to investigate whether geotracking can be used as a basis for determining rent. To answer this, the report has been divided after three, for geotracking, basic conditions. These are technology, rent determination and integrity. The result of the study shows that there is a need to optimize the rent determination of stores to meet future challenges. It also shows that the three basic conditions for geotracking can be met, why it is advisable to use geotracking when determining rent for a shop space.
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A Personal Place Awareness SystemSnow, Bradford Jason 20 April 2005 (has links)
No description available.
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Digital signal processing extra-tropical cyclones warning system using WiMAXAl-Breiki, Mohamed Ahmed Mohamed Naser January 2013 (has links)
This research project proposed a unique solution to make use of these base stations to keep all subscribers alerted with warning of possible disaster should that be required. As the current, network does not provide a provision for such a noble approach, a new network model has been developed and simulated to interface a sensor (weather station, WeS), with WiMAX weather station. The weather station is based on DSP processor to receive a digitised sensor values, process these values, analyse them and if they fall within the alert zones, packet them according to WiMAX protocol and send them to subscribers. The developed standard bypasses any commercial network to offer free transmission to subscribers. This setup is also able to extract information on weather condition or react on uncertainty, i.e. disaster scenarios. Natural disasters, such as torrent, tornado/ hurricane, volcano eruption, earthquake, Tsunamis or landslide are increasing. Unfortunately they bring with them human tragedies, environment catastrophes, villages, cities and counties are subject to endless devastation during and after the destructive forces. Water, electricity and gas supply are most disrupted and difficult to restore in short time. However, communication is another item that can be affected adversely but WLAN with specific considerations, should be excluded from the effect. This project presents a solution, albeit minor relative to the maximum effect of the disaster, but will keep the telecommunication/communication in operation. Our novel technique, a “Clone Wireless Wide Area Network (CloneWAN)” is a clone wireless network to the wired Network. In the event of natural calamities, it gives continuity of network operation. It is based on WiMAX. The realization of CloneWAN has been formed and simulated to set the national network of the UAE at its correct form. CloneWAN model has been simulated with Opnet platform. All results revealed that the model is complete. The interface to Alerting System is discussed. Results show that the dynamic behavior of the parameters delay and Throughput of CloneWAN model is stable over various and different load scenarios. WiMAX is a de-facto standard in the current and future network requirement standards. Its main component is the Base Station which is normally stationed in the air, high enough to couple signals from other base stations. It is purpose is merely focused on networking signals for commercial purposes. The suggested hardware interface for the Weather Station is based on DSP SHARC processor. The model has been written in C and simulated under Opnet package. A number of scenarios have been set to represent different disasters worldwide. All results are listed and discussed later in the thesis.
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Arquitectura e Implementación de una Wireless Lan para una empresa usando el 802.11bMadrid Cisneros, Juan Francisco January 2006 (has links)
El presente trabajo de tesis se ha desarrollado en cinco capítulos mediante la descripción de la tecnología WIFI y sus aplicaciones mediante el estándar 802.11b.
En el Capítulo 1 se describe la tecnología inalámbrica,su funcionamiento,arquitectura y los protocolos involucrados en la performance de las tramas características asi como la seguridad en las wlan.
En el Capítulo 2 se abordarán las ventajas y desventajas, planificación de las frecuencias,soluciones indoor,outdoor y los diferentes componentes de una red inalámbrica.
En el Capítulo 3 se desarrollara con detalle un proyecto de aplicación de un enlace inalámbrico del modo bridge usando el estándar 802.11b en los locales comercial y central en la Empresa Municipal de Agua Potable y Alcantarillado de San Martín S.A. detallándose las etapas de dicho proyecto,pruebas,ingeniería del proyecto,análisis indoor y outdoor.Asimismo se plantean una serie de actividades que verificarán el desempeño de las redes construidas junto con los costos de las etapas respectivas.
En el Capítulo 4 se desarrollara el estudio de factibilidad del proyecto y los factores a considerar como tambien el análisis DOFA como criterio de decisión en la implementación y su justificación financiera teniendo como proyección 5 años para cumplir las metas específicas de la empresa.
En el Capítulo 5 se desarrollan las conclusiones y recomendaciones correspondientes así como los anexos correspondientes a las soluciones UMA y la normatividad vigente en nuestro país.
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Estimating the number of people in an area : Using Bluetooth and WiFi signalsNaga, Alex January 2019 (has links)
In this world of the digital era, a large percentage of the world population and almost everyone in Sweden today owns a smartphone, and possibly even a smartwatch. By using this to our advantage, it would be possible to check whether an area is currently very busy or not, based on how many smartphones or other wearables technology it is possible to discover in the area. The approach chosen to dig into this problem was to research suitable hardware devices with Bluetooth and WiFi compatibility, that could detect probe requests broadcasted by smartphones or wearable devices in the area. The knowledge gained from the research in this thesis set the foundation for implementing a prototype with the desired functionality. Testing of the prototype was then conducted in a university library and analysed how it performed. Through testing the developed prototype, it revealed that it is possible to obtain an indication of whether an area is currently very crowded or not using Bluetooth and WiFi signals. A suggestion on how to proceed in creating more fine-tuned improvements is also described.
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Precise Tracking of Things via Hybrid 3-D Fingerprint Database and Kernel Method Particle FilterBargshady, Nader 23 August 2017 (has links)
"Precise Tracking of Things (PToT) using RF signals has posed a serious challenge in an indoor environment. The precision localization information is an enabler for better coordinated-tasks and is essential for a successful launch of many emerging applications. PToT relies on two principal components, a novel navigation (tracking) algorithm, and a hybrid 3D fingerprint database. In this dissertation, we begin by using the two widely known ranging techniques, Time Of Arrival (TOA) associated with Ultra-wideband (UWB) and Received Signal Strength (RSS) with WiFi signals. First, we use the theoretical models derived from empirical measurement of TOA and RSS to analyze the performance of hybrid (WiFi & UWB) cooperative localization accuracy in a multi-robot operation in a typical office environment. To measure the performance of this hybrid localization, we derive a mathematical formulation for the Crame ́r-Rao-Lower- Bound (CRLB). The hybrid method shows more accuracy over WiFi-only approach. In achieving more precision, we extend our work. Second, we introduce a novel approach, a Kernel Method Particle Filter (KMPF) for tracking and predicting the position by accessing the information created by hybrid 3D fingerprint database. We derive the mathematical and statistical framework for the Particle Filter based on the statistical assumptions about the behavior of channel models. We also describe the formation of one of the necessary PToT component, a 3D fingerprint database. We compare the performance of the KMPF against the CRLB using WiFi signal channel models."
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