Dissertations / Theses: 'Wi-Fi Sensors'

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Ta, Viet-Cuong. "Smartphone-based indoor positioning using Wi-Fi, inertial sensors and Bluetooth." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAM092/document.

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Grâce à l’émergence dans la vie quotidienne des appareils de plus en plus populaires que sont les smartphones et les tablettes, la tâche de postionner l'utilisateur par le biais de son téléphone est une problématique fortement étudiée dans les domaines non seulement de la recherche mais également des communautés industrielles. Parmi ces technologies, les approches GPS sont devenues une norme et ont beaucoup de succès pour une localisation en environnement extérieur. Par contre, le Wi-Fi, les capteurs inertiels et le Bluetooth sont plutôt préférés pour les tâches de positionnement dans un environnement intérieur.Pour ce qui concerne le positionnement des smartphones, les approches basées sur les « empreintes digitales » (fingerprint) Wi-Fi sont bien établies. D'une manière générale, ces approches tentent d'apprendre la fonction de correspondance (cartographie) des caractéristiques du signal Wi-Fi par rapport à la position de l’appareil dans le monde réel. Elles nécessitent généralement une grande quantité de données pour obtenir une bonne cartographie. Lorsque ces données d'entraînement disponibles sont limitées, l'approche basée sur les empreintes digitales montre alors des taux d’erreurs élevés et devient moins stable. Dans nos travaux, nous explorons d’autres approches, différentes, pour faire face à cette problématique du manque de données d'entraînement. Toutes ces méthodes sont testées sur un ensemble de données public qui est utilisé lors d’une compétition internationale à la Conférence IPIN 2016.En plus du système de positionnement basé sur la technologie Wi-Fi, les capteurs inertiels du smartphone sont également utiles pour la tâche de suivi. Les trois types de capteurs, qui sont les accéléromètres, le gyroscope et la boussole magnétique, peuvent être utilisés pour suivre l'étape et la direction de l'utilisateur (méthode SHS). Le nombre d'étapes et la distance de déplacement de l'utilisateur sont calculés en utilisant les données de l'accéléromètre. La position de l'utilisateur est calculée par trois types de données avec trois méthodes comprenant la matrice de rotation, le filtre complémentaire et le filtre de Madgwick. Il est raisonnable de combiner les sorties SHS avec les sorties de Wi-Fi, car les deux technologies sont présentes dans les smartphones et se complètent. Deux approches combinées sont testées. La première approche consiste à utiliser directement les sorties Wi-Fi comme points de pivot pour la fixation de la partie de suivi SHS. Dans la deuxième approche, nous comptons sur le signal Wi-Fi pour construire un modèle d'observation, qui est ensuite intégré à l'étape d'approximation du filtre à particules. Ces combinaisons montrent une amélioration significative par rapport au suivi SHS ou au suivi Wi-Fi uniquement.Dans un contexte multiutilisateur, la technologie Bluetooth du smartphone pourrait fournir une distance approximative entre les utilisateurs. La distance relative est calculée à partir du processus de numérisation du périphérique Bluetooth. Elle est ensuite utilisée pour améliorer la sortie des modèles de positionnement Wi-Fi. Nous étudions deux méthodes. La première vise à créer une fonction d'erreur qui permet de modéliser le bruit dans la sortie Wi-Fi et la distance approximative produite par le Bluetooth pour chaque intervalle de temps spécifié. La seconde méthode considère par contre cette relation temporelle et la contrainte de mouvement lorsque l'utilisateur se déplace. Le modèle d'observation du filtre à particules est une combinaison entre les données Wi-Fi et les données Bluetooth. Les deux approches sont testées en fonction de données réelles, qui incluent jusqu'à quatre utilisateurs différents qui se déplacent dans un bureau. Alors que la première approche n'est applicable que dans certains scénarios spécifiques, la deuxième approche montre une amélioration significative par rapport aux résultats de position basés uniquement sur le modèle d'empreintes digitales Wi-Fi
With the popularity of smartphones and tablets in daily life, the task of finding user’s position through their phone gains much attention from both the research and industry communities. Technologies integrated in smartphones such as GPS, Wi-Fi, Bluetooth and camera are all capable for building a positioning system. Among those technologies, GPS has approaches have become a standard and achieved much success for the outdoor environment. Meanwhile, Wi-Fi, inertial sensors and Bluetooth are more preferred for positioning task in indoor environment.For smartphone positioning, Wi-Fi fingerprinting based approaches are well established within the field. Generally speaking, the approaches attempt to learn the mapping function from Wi-Fi signal characteristics to the real world position. They usually require a good amount of data for finding a good mapping. When the available training data is limited, the fingerprinting-based approach has high errors and becomes less stable. In our works, we want to explore different approaches of Wi-Fi fingerprinting methods for dealing with a lacking in training data. Based on the performance of the individual approaches, several ensemble strategies are proposed to improve the overall positioning performance. All the proposed methods are tested against a published dataset, which is used as the competition data of the IPIN 2016 Conference with offsite track (track 3).Besides the positioning system based on Wi-Fi technology, the smartphone’s inertial sensors are also useful for the tracking task. The three types of sensors, which are accelerate, gyroscope and magnetic, can be employed to create a Step-And-Heading (SHS) system. Several methods are tested in our approaches. The number of steps and user’s moving distance are calculated from the accelerometer data. The user’s heading is calculated from the three types of data with three methods, including rotation matrix, Complimentary Filter and Madgwick Filter. It is reasonable to combine SHS outputs with the outputs from Wi-Fi due to both technologies are present in the smartphone. Two combination approaches are tested. The first approach is to use directly the Wi-Fi outputs as pivot points for fixing the SHS tracking part. In the second approach, we rely on the Wi-Fi signal to build an observation model, which is then integrated into the particle filter approximation step. The combining paths have a significant improvement from the SHS tracking only and the Wi-Fi only. Although, SHS tracking with Wi-Fi fingerprinting improvement achieves promising results, it has a number of limitations such as requiring additional sensors calibration efforts and restriction on smartphone handling positions.In the context of multiple users, Bluetooth technology on the smartphone could provide the approximated distance between users. The relative distance is calculated from the Bluetooth inquiry process. It is then used to improve the output from Wi-Fi positioning models. We study two different combination methods. The first method aims to build an error function which is possible to model the noise in the Wi-Fi output and Bluetooth approximated distance for each specific time interval. It ignores the temporal relationship between successive Wi-Fi outputs. Position adjustments are then computed by minimizing the error function. The second method considers the temporal relationship and the movement constraint when the user moves around the area. The tracking step are carried out by using particle filter. The observation model of the particle filter are a combination between the Wi-Fi data and Bluetooth data. Both approaches are tested against real data, which include up to four different users moving in an office environment. While the first approach is only applicable in some specific scenarios, the second approach has a significant improvement from the position output based on Wi-Fi fingerprinting model only

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Aaro, Gustav. "Smartphone Based Indoor Positioning Using Wi-Fi Round Trip Time and IMU Sensors." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166340.

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While GPS long has been an industry standard for localization of an entity or person anywhere in the world, it loses much of its accuracy and value when used indoors. To enable services such as indoor navigation, other methods must be used. A new standard of the Wi-Fi protocol, IEEE 802.11mc (Wi-Fi RTT), enables distance estimation between the transmitter and the receiver based on the Round-Trip Time (RTT) delay of the signal. Using these distance estimations and the known locations of the transmitting Access Points (APs), an estimation of the receiver’s location can be determined. In this thesis, a smartphone Wi-Fi RTT based Indoor Positioning System (IPS) is presented using an Unscented Kalman Filter (UKF). The UKF using only RTT based distance estimations as input, is established as a baseline implementation. Two extensions are then presented to improve the positioning performance; 1) a dead reckoning algorithm using smartphone sensors part of the Inertial Measurement Unit (IMU) as an additional input to the UKF, and 2) a method to detect and adjust distance measurements that have been made in Non-Line-of-Sight (NLoS) conditions. The implemented IPS is evaluated in an office environment in both favorable situations (plenty of Line-of-Sight conditions) and sub-optimal situations (dominant NLoS conditions). Using both extensions, meter level accuracy is achieved in both cases as well as a 90th percentile error of less than 2 meters.

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Fabre, Léa. "Contributions and Opportunities of Wi-Fi Data to Improve Transport Demand Knowledge / Utilisation de données Wi-Fi, quels apports pour la connaissance de la demande de transport?" Electronic Thesis or Diss., Lyon 2, 2024. http://www.theses.fr/2024LYO20011.

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La mobilité joue un rôle clé dans les paysages urbains, en particulier, les transports en commun sont essentiels au bon fonctionnement des villes. Par conséquent, il est nécessaire de planifier les systèmes de transport en commun afin de leur garantir un fonctionnement efficace. Pour cela, il est important d'avoir une bonne connaissance de la demande de transport en commun, d'autant plus dans un monde en constante évolution.Actuellement, nous observons une forte croissance démographique mondiale ainsi qu'un important étalement urbain, deux facteurs qui sont les principales causes de l'augmentation de la demande de transport urbain. À cela il faut ajouter une forte tendance à la diversification des comportements de mobilité, principalement due à l'émergence de nouveaux modes de transport. Les données traditionnellement utilisées pour prévoir cette demande, et pour la planification des transports de manière générale, ne sont plus à même de refléter ces changements dans les comportements de mobilité. Le développement des technologies de l'information, la digitalisation et le boom de la science des données sont autant de nouvelles opportunités pour la prévision de la demande de transport. Le développement de nouveaux outils et algorithmes, notamment issus de l'intelligence artificielle, contribuent à la diversification et participent à complexifier les modèles pour améliorer la prévision des comportements de mobilité. En parallèle, nous observons également une grande diversification des données utilisées dans la recherche en transport. Parmi ces nouvelles sources de données, les données Wi-Fi sont très prometteuses. Ces données présentent des avantages significatifs lorsqu'elles sont utilisées pour la planification des transports (collectées en continue, de manière passive, elles apportent des informations sur les trajets Origine-Destination…). Cependant, les données Wi-Fi présentent aussi quelques inconvénients. Ainsi elles doivent être traitées avant d'être utilisées dans des modèles de prévision de la demande. En tant que nouvelle méthode de collecte de données sur la mobilité, des questions subsistent quant à la qualité des données, à leur contribution dans le domaine et à la manière dont elles peuvent être utilisées.L'objectif de cette thèse est de fournir une approche clé en main de l'utilisation des données Wi-Fi pour la connaissance des comportements de mobilité. Dans cette thèse, nous proposons donc des solutions pour traiter ces données au fort potentiel. Nous présentons tout d'abord une méthodologie pour filtrer les signaux parasites détectés par les capteurs Wi-Fi de manière à ne construire la matrice Origine-Destination qu'avec les signaux provenant de passagers. Le redressement des données Wi-Fi pour pallier aux erreurs de prédiction des volumes de passagers du fait de signaux non détectés est également traité. Au final, ces méthodes permettent d'obtenir des matrices Origine-Destination à la fois pertinentes pour la structure des déplacements et complètes dans les volumes de déplacements. Dans cette thèse, nous proposons également un modèle pour quantifier l'erreur entre la matrice Origine-Destination produite par les données Wi-Fi et les déplacements Origine-Destination réels, malgré la rare disponibilité de ces derniers. Quelques applications pour l'utilisation des données Wi-Fi sont également présentées. Pour conclure, les résultats de cette thèse montrent que les données Wi-Fi peuvent enrichir la connaissance des comportements de mobilité, de manière continue et à faible coût
Due to its social, environmental and economic importance, mobility plays a key role in urban landscapes. In particular, public transportation is critical to the smooth functioning of cities. Therefore, public transportation systems must be planned to operate properly and efficiently. To this end, it is of paramount importance to have a great knowledge of the mobility demand, especially in an evolving world. The world today is facing a significant demographic growth along with urban sprawl, which implies an increasing demand for transportation in the cities. In addition, travel patterns are diversifying and becoming less regular, mainly due to the emergence of new modes of transport. The data traditionally used for public transportation planning are inadequate to reflect these changes in mobility behaviors. The development of information technologies, digitization and the data science boom can bring interesting benefits to the forecasting of transport demand. The development of new tools and algorithms, such as artificial intelligence, contributes to the diversification and complexity of models to improve the prediction of mobility behaviors. In parallel, we are currently witnessing the diversification of data sources used in mobility analyses. Among them, Wi-Fi data are very promising. These data have significant advantages when used in transportation planning (they provide information on Origin-Destination trips, they are collected continuously and passively…). However, Wi-Fi data also have some drawbacks. Therefore, they require further processing to be used in demand forecasting models. As a new way of collecting mobility data, questions remain about the quality of the data, their contribution, and how they can be used. The objective of this thesis is to provide a data-driven approach to the use of Wi-Fi data for mobility behaviors. In this thesis, we therefore propose solutions to process this interesting data source. A methodology is presented to filter the parasite signals detected by Wi-Fi sensors in order to keep only the passenger signals and construct relevant Origin-Destination matrices. Scaling of the Wi-Fi data to avoid errors in the predicted total number of trips due to undetected Wi-Fi devices is also handled. In the end, we provide Origin-Destination matrices that are relevant to the structure of the trips and complete in trip volumes. In addition, we propose a modeling to quantify the error between the Origin-Destination matrix produced by Wi-Fi data and real Origin-Destination trips, despite the non-continuous availability of the latter. Some applications of the use of Wi-Fi data are also presented. In conclusion, the results of this thesis show that interesting insights into mobility behaviors can be derived from Wi-Fi data, continuously and at low cost

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Danielsson, Simon, and Jakob Flygare. "A Multi-Target Graph-Constrained HMM Localisation Approach using Sparse Wi-Fi Sensor Data." Thesis, KTH, Optimeringslära och systemteori, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231090.

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This thesis explored the possibilities of using a Hidden Markov Model approach for multi-target localisation in an urban environment, with observations generated from Wi-Fi sensors. The area is modelled as a network of nodes and arcs, where the arcs represent sidewalks in the area and constitutes the hidden states in the model. The output of the model is the expected amount of people at each road segment throughout the day. In addition to this, two methods for analyzing the impact of events in the area are proposed. The first method is based on a time series analysis, and the second one is based on the updated transition matrix using the Baum-Welch algorithm. Both methods reveal which road segments are most heavily affected by a surge of traffic in the area, as well as potential bottleneck areas where congestion is likely to have occurred.
I det här examensarbetet har lokalisering av gångtrafikanter med hjälp av Hidden Markov Models utförts. Lokaliseringen är byggd på data från Wi-Fi sensorer i ett område i Stockholm. Området är modellerat som ett graf-baserat nätverk där linjerna mellan noderna representerar möjliga vägar för en person att befinna sig på. Resultatet för varje individ är aggregerat för att visa förväntat antal personer på varje segment över en hel dag. Två metoder för att analysera hur event påverkar området introduceras och beskrivs. Den första är baserad på tidsserieanalys och den andra är en maskinlärningsmetod som bygger på Baum-Welch algoritmen. Båda metoderna visar vilka segment som drabbas mest av en snabb ökning av trafik i området och var trängsel är troligt att förekomma.

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Skytte, Joakim. "Feasibility Study of Indoor Positioning in a Hospital Environment Using Smartphone Sensors." Thesis, Linköpings universitet, Reglerteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-145172.

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This thesis is a feasibility study of contemporary indoor positioning approaches in an hospital environment using sensor available on Android phones together with Wi-Fi fingerprintingand map information. The purpose is to determine the resolution of pedestrian indoor positioning and whether it is sufficient for room level accuracy. Accurate and robust positioning for outdoor applications based on mobile networks and satellite systems, such as the Global Positioning Service (GPS), has been around for many years. However these systems are not suitable for positioning inside buildings due to a high level of signal degradation. Through the years various pedestrian indoor positioning methods have been proposed.A simple algorithm for suppressing random movement of the mobile phone is tested. Two versions of the Extended Kalman Filter (EKF) are compared for fusing the Inertial Navigation System (INS) measurements during Pedestrian Dead Reckoning (PDR). The TRIAD algorithm is tested for suppressing the effects of large magnetic disturbances. Wi-Fi fingerprinting using two combinations of positioning algorithms and radio maps is tested. The EKF is tested for fusing PDR and Wi-Fi fingerprint position estimations. The Particle Filter (PF) is tested for combining PDR with Wi-Fi fingerprint positioning with a geometrical map. Static Received Signal Strength Indication (RSSI) measurements are carried out to detect variable Wi-Fi transmission power. The results show that adding more informations sources improves the positioning performance. Also fusion using PF outperforms the EKF in more complex indoor environments and movement patterns.
En starkt växande tillgång och kapacitet hos trådlösa nätverk i kombination med explosionen inom mobiltelefoni, i synnerhet vad gäller smartphones, har lett till ett enormt ökat intresse för och utveckling inom området inomhuspositionering. Det har under många år funnits lösningar för positionering i utomhusmiljöer, exempelvis GPS och triangulering med mobila basstationer, men inga av dessa system lämpar sig för inomhuspositionering eftersom signalerna tappar alldeles för mycket i intensitet när användaren befinner sig inomhus. Under årens lopp har flera olika lösningar för inomhuspositionering föreslagits. I denna uppsats testas olika lösningar för inomhuspositionering med smartphones i en sjukhusmiljö. Testen baserar sig på de sensorer som finns i en smartphone med operativsystemet Android i kombination med Wi-Fi triangulering och en digital planlösning över testområdet. Syftet är att undersöka om noggrannheten kan bli såpass så bra att en upplösning på rumsnivå uppnås. En enkel algoritm för att kompensera för slumpartade och oplanerade rörelser hos mobiltelefonen testas. Två versioner av det utökade Kalmanfiltret testas för tröghetsnavigering. TRIAD algoritmen testas för att motverka magnetiska störningar. Två kombinationer av radiokartor och positioneringsalgoritmer provas för att genomföra Wi-Fi positionering. Ett utökat Kalmanfilter används för att kombinera resultaten av tröghetsnavigeringen med Wi-Fi positioneringen. Ett partikelfilter används för att utföra sensorfusionen av tröghetsnavigeringen, Wi-Fi positioneringen och den digitala planlösningen. Resultaten visar att ju mer information som tillförs under positioneringen desto större blir noggrannheten samt att partikelfiltret ger en bättre noggrannhet i en komplex inomhusmiljö i kombination med komplicerade rörelsemönster än det utökade Kalmanfiltret.

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Zewdu, Yesitla Ephrem. "Survey of microcontrollers and short-range radio transceivers for wireless sensors." Thesis, Mittuniversitetet, Institutionen för elektronikkonstruktion, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-39640.

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A significant growth was witnessed in the field of Wireless Sensor Networks (WSNs), in the previous decade. The objective of this study has been Survey of micro controllers and short-range radio transceivers for wireless sensors and provide an extensive overview of micro controllers and RF-transceivers in the Market and compare the relevant properties for designing wireless sensor nodes. In the survey, RF-transvers from Nordic semiconductors is extensively presented for short-rang wireless protocols some of the protocols are RF-Communication Module, Bluetooth Low Energy Module, ZigBee module and Wi-Fi module. In WSNs node design Power consumption is one the most important design issue, this thesis work present the different type of WSN protocols energy consumption efficiency and power consumption, compared and conclude graphically. Microcontrollers are the main part of WSNs node for processing and gathering sensor data. There is different microcontroller’s products in the market however the WSN protocols presented in this thesis uses Cortex-M4 processor which is one of ARM product, the specification and comparison of this product with other products is presented.

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Waikul, Devendra Mahendra. "BLUETOOTH-ENABLED ENERGY MONITORING SYSTEM WITH WIRELESS DATA ACQUISITION USING WEB SERVER." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1596563312207117.

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Dorazil, Jan. "Bezdrátové senzorové sítě s využitím mobilních zařízení." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2013. http://www.nusl.cz/ntk/nusl-236372.

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This master's thesis deals with the idea of using mobile devices as sensor nodes in wireless sensor network. Focused mostly on Android platform, we explore possibilities of wireless communication, and describe various types of sensors on mobile devices. We design and implement wireless sensor network based on mobile devices running Android operating system. The network performs real-time capturing of data from all sensors available and optionally from GPS. All measurements are visualized at the base station, which is Java Standard Edition desktop application. Wi-Fi, Bluetooth or even cellular internet can be used for communication within the network. Nodes can be remotely configured via SMS messages.

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Miccoli, Roberta. "Implementation of a complete sensor data collection and edge-cloud communication workflow within the WeLight project." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/22563/.

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This thesis aims at developing the full workflow of data collection from a laser sensor connected to a mobile application, working as edge device, which subsequently transmits the data to a Cloud platform for analysing and processing. The project is part of the We Light (WErable LIGHTing for smart apparels) project, in collaboration with TTLab of the INFN (National Institute of Nuclear Physics). The goal of We Light is to create an intelligent sports shirt, equipped with sensors that take information from the external environment and send it to a mobile device. The latter then sends the data via an application to an open source Cloud platform in order to create a real IoT system. The smart T-shirt is capable of emitting different levels of light depending on the perceived external light, with the aim of ensuring greater safety for road sports people. The thesis objective is to employ a prototype board provided by the CNR-IMAMOTER to collect data and send it to the specially created application via Bluetooth Low Energy connection. Furthermore, the connection between the edge device and the Thingsboard IoT platform is performed via MQTT protocol. Several device authentication techniques are implemented on TB and a special dashboard is created to display data from the IoT device; the user is also able to view data in numerical and even graphical form directly in the application without necessarily having to access TB. The app created is useful and versatile and can be adapted to be used for other IoT purposes, not only within the We Light project.

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Fernandes, Rui Miguel Félix. "Object signature in radio frequency." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13708.

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Mestrado em Engenharia Eletrónica e Telecomunicações
The RF signature can be consider as a fingerprint of an object when submitted to electromagnetic radiation. Based on this concept, the initial goal of this work was to elaborate a comparative analysis of the Radio Frequency signature of different materials. Through the design of a prototype based on an adapted Wi-Fi network was developed an innovative system capable of distinguishing materials with the analysis of their interference in the propagated channel. In order to refine this distinction was utilized a signal processing tool, the Wavelet Transform. This technique serve as support tool of the system for a better differentiation of the studied targets. The versatility of this concept was proved through the analysis of signatures of static targets like metal, wood and plastic, as well as moving targets, giving the example of a moving human. Due to the promising results obtained, the initial objective of the work was expanded being also presented in this document the concept of intruder detection through a Wi-Fi network by the analysis of the Wavelet coefficients.
A Assinatura em Rádio Frequência pode ser considerada como a impressão digital que um objeto manifesta quando submetido a radiação eletromagnética. O objetivo inicial deste trabalho era a elaboração de uma análise comparativa das assinaturas em Rádio Frequência de diferentes materiais. Tendo por base uma rede Wi-Fi adaptada, foi desenvolvido um sistema inovador capaz de distinguir materiais pela análise da interferência dos mesmos no canal de propagação. Com vista a melhorar o desempenho do protótipo inicial, o sinal recebido foi processado através da Transformada de Wavelet. Esta técnica serviu como ferramenta de suporte do sistema para a obtenção de uma diferenciação mais clara dos alvos estudados. Demonstrando a versatilidade deste conceito foram avaliadas as assinaturas de alvos estáticos como o metal, madeira e plástico bem como de alvos móveis dando, como exemplo, uma pessoa em movimento. Devido aos resultados promissores obtidos, o objetivo inicial do sistema foi alargado estando também presente neste documento o conceito de deteção de intrusos através de uma rede Wi-Fi pela análise dos coeficientes de Wavelet.

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Bezdíček, Jan. "Telemetrie pro formuli Dragon IV." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2014. http://www.nusl.cz/ntk/nusl-236045.

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The aim of this master's thesis was to design and construct complete telemetry system for the student formula Dragon IV constructed for international Formula Student competition. At first, the work deals with the measurement of the physical quantities, telemetry system and automotive sensors of the formula, their mutual communication and communication with the CAN bus. It also describes the procedure of hardware design including choosing right inertial sensors and a GPS module and their using in telemetry system. The work contains materials for production of two-layer printed circuit board extending the microcomputer BeagleBone Black on the inertial sensors and the GPS module. The bigger part of the telemetry system is the firmware for hardware and software for the computer user. Both written in programming language C++ and C# are included in this work as well. This user application serves for wireless receiving data from the hardware and their showing and logging. In addition this user application can be used for wireless hardware configuration. The final product is the complete telemetry system and it is suitable for selling to end customer.

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Pereira, Rui Jorge Santos. "Supervisão e controlo remoto da iluminação na via pública." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17306.

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Mestrado em Engenharia Mecânica
Esta dissertação faz uma abordagem à problemática da e ciência energética em sistemas de iluminação pública. A principal motivação prende-se com o consumo signi cativo que a parcela energética destes sistemas ocupa nas economias das autarquias, visto que em Portugal, no ano 2013 foram gastos mais de 100 Milhões de Euros em energia na Iluminação Pública. Os recentes desenvolvimentos na iluminação LED de alta potência permitem novas soluções para a iluminação pública, que são signi cativamente mais e cientes do ponto de vista energético. O presente trabalho estuda os princípais tipos de iluminação, soluções de controlo existentes e tecnologias de suporte que permitiram desenvolver um sistema robusto, autónomo, e, sobretudo, de baixo custo. Para tal, foram desenvolvidos dois tipos de módulos (os slave's e o master), com diversos constituintes, que serão abordados ao longo da dissertação. Cada luminária contém um desses módulos (uma com o master e as restantes com os slave's) e todas elas comunicam por radio-frequência em cascata, permitindo a transmissão de mensagens de avisos/avarias, consumos e movimento detetados pelos sensores. O conteúdo das variáveis de consumos, avarias/avisos e temperatura são enviadas via GPRS, atravéz do módulo master, para uma base de dados externa instalada numa placa raspberry. Ao nivel de interação com o sistema, a página website alojada no raspberry permite, entre outras coisas, visualizar avarias sobre uma aplicação do Google Maps e analisar um grá co de consumos e temperatura. É também possível a de nição de períodos de tempo em que a iluminação funcionará, sendo útil essencialmente em eventos ocasionais (exemplo de festividades).
This thesis is an approach to the problem of energy e ciency in public light systems. The main motivation is related to the signi cant energy consumption these systems takes from the economies of local authorities. In Portugal, for example, during 2013, it was spent over 100 million euros in public lighting energy. Recent developments in high power LED lighting enable new solutions for public lighting that are signi cantly more e cient. This dissertation studies the main types of lighting, the existing monitoring solutions and supporting technologies which enable the development of a robust, autonomous and, above all, inexpensive system. For that, it were developed two types of modules (The slave's and the master) with various components, which will be addressed throughout the dissertation. Each lamp contains one of these modules and they all communicate by radio-frequency, allowing the transmission of warning messages/malfunctions, and sensor information (motion detection and consumed power). The content of the consumption variables, faults/warnings and temperature are sent via GPRS through the master module to an external database installed on a plate raspberry. In terms of the interaction with the system, the website hosted on the page raspberry allows, among other things, to view errors on an application of Google Maps and to analyse a consumption and temperature chart. It is also possible to de ne the time periods when the lighting is functioning, which is useful mainly for occasional events (festivals, for example).

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Ribeiro, João Luís Carvalho Ferreira. "Survey of public transport routes using Wi-Fi." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23458.

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Mestrado em Engenharia de Computadores e Telemática
An important aspect in improving public transport eﬃciency is collecting information regarding traveler routes, usually represented as an OriginDestination (OD) matrix. Most public transportation systems implement fare collection systems that can provide the accurate origins of traveler routes but not accurate destinations. In this dissertation we look at WiFi, more speciﬁcally 802.11 data-link layer, as a candidate to provide OD matrix estimations. We present an algorithm capable of collecting information regarding Wi-Fi capable devices inside the bus complemented with positioning and time. A system is also presented to implement this concept using minimal requirements. An implementation of this system was deployed in a public bus to collect data for several weeks. This resulted on over 15000 traveler routes collected in 9 diﬀerent days. This data was contextualized and mapped to an OD system in order to demonstrate how it can be used to generate OD matrix estimations.
Um aspecto importante na melhoria da eﬁciência de transportes públicos consiste na recolha de percursos de passageiros, frequentemente representados na forma de matrizes Origem-Destino (OD). Grande parte dos sistemas de transportes públicos implementa sistemas de bilhética que são capazes de fornecer com precisão a origem dos percursos efectuados pelos passageiros, mas não o destino. Nesta dissertação foi selecionada a tecnologia Wi-Fi como um candidata a fornecer leituras de precisão para estimar matrizes OD. Apresentamos um algoritmo capaz de recolher informação sobre dispositivos que suportam Wi-Fi, dentro de um autocarro público, acoplada com informação sobre posicionamento e tempo. É também apresentado um sistema que implementa este conceito ao usar requisitos mínimos. Uma implementação deste sistema foi colocada num autocarro público para efectuar recolha de dados durante várias semanas. Mais de 15000 percursos foram recolhidos em 9 dias diferentes. Estes dados foram contextualizados e mapeados num sistema OD para demonstrar como podem ser usado para estimar matrizes OD.

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Kalo, Alexander. "Hantering av mät-filer från Wi-Fi fjärrkontroll." Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-185796.

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A measuring system Striton has been developed at the department of biomedicalengineering, University Hospital of Umeå, for motion analysis using motion sensors whichattaches to the patient’s lower body to assess the risk for potential neurological andmusculoskeletal damage. The measuring system is comprised of two motion sensor unitsand a remote control where data is gathered based on step height, step width, theorientation of the calves and step frequency. The motion sensor units which attach to thecalves are comprised of a MCU with a built in Wi-Fi module, a IMU and and time-of-flightsensors. Data is transferred through Wi-Fi and stored on a SD-card as CSV-files on theremote control which is comprised of a Raspberry Pi Zero WH running a Linux operatingsystem (Raspbian). The remote control also has the functions to initiate and complete ameasurement as well as mark an event. The extraction of data from the remote control toanother unit for analysis occurs through SSH and SFTP using third-party programs whichmay require technical knowledge. A unique software was designed specifically for Stritonfor the operating system Windows 10 using Visual Studio (2019) which provides thefunctions to connect to a predefined Wi-Fi access point as well as automatically reconnectto previously connected access point at shutdown, connect through SFTP, list the savedfiles on the remote control, perform file operations, synchronize the date and time on theremote control as well as change settings in the software which is saved locally in a settingsfile. The user interface is minimalistic with the intention to reduce complexity and timerequirement to extract the data from the measuring system Striton.
Ett mätsystem Striton har utvecklats av CMTS, Medicinsk Teknik – FoU på NorrlandsUniversitetssjukhus för rörelseanalys med hjälp av rörelsesensorer som fästs på patientensunderben för att bedöma en potentiell neurologisk samt muskuloskeletal skada.Mätsystemet består av två sensorenheter samt en fjärrkontroll där data samlas in baseratpå höjd av steg, stegbredd, underbenens orientering samt stegfrekvens. Sensorenheternasom fästs på underbenen består av en MCU med inbyggd Wi-Fi modul, IMU och time-offlight sensorer. Data förs över via Wi-Fi och lagras på ett SD-kort i form av CSV-filer påfjärrkontrollen beståendes av en Raspberry Pi Zero WH som driver ett Linuxoperativsystem (Raspbian). Fjärrkontrollen har även funktionerna att kunna starta ochstoppa en mätning samt markera en händelse. Extrahering av data från fjärrkontrollen tillen annan enhet för analys sker via SSH och SFTP med hjälp av tredjepartsprogram som kankräva teknisk kunskap. En unik programvara designades specifikt för Striton tilloperativsystemet Windows 10 i miljön Visual Studio (2019) och tillhandahålleregenskaperna att kunna ansluta till en bestämd Wi-Fi åtkomstpunkt samt automatisktåteransluta till föregående åtkomstpunkt vid avslut, ansluta via SFTP, visa sparade filer frånfjärrkontrollen, utföra filoperationer, synkronisera datum och tid på fjärrkontrollen samtändra inställningar i programvaran som sparas i en lokal inställningsfil. Gränssnittet ärminimalistiskt med syfte att reducera komplexiteten samt tidsåtgången för extrahering avdata från mätsystemet Striton.

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Liu, Guanxiong. "Modeling and Performance Analysis of Hybrid Localization Using Inertial Sensor, RFID and Wi-Fi Signal." Digital WPI, 2015. https://digitalcommons.wpi.edu/etd-theses/514.

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The development in wireless technology, mobile smart devices and Internet of Things has gave birth to a booming era or the wireless indoor geolocation. This technology have been increasingly used within our daily life and help people to build up the tracking system which could be used by fulfillment centers and grocery stores. To achieve higher localization accuracy with wireless geolocation, we need a higher density of deployment which involves high deployment and maintenance cost. To balance the accuracy and the cost, people have begun using wireless localization employing inertial navigation system (INS) which provide speed and direction of movement. When we combine Radio Frequency (RF) localization with INS, we have a hybrid INS/RF localization system which can achieve high localization accuracy with low cost. In this thesis, we use accelerometers and magnetometers in an Android smart phone to build a hybrid INS/RF system and use two different technologies for RF localization: Radio Frequency Identification Device (RFID) and Wi-Fi. Using this system, we conducted measurements of the hybrid localization system and evaluate its performance. The specific contributions of the thesis are: (1)Empirical performance evaluation of the INS/RFID localization system. It relates the localization error to the number and position of RFID tags. (2)Model the effect of metallic objects on accuracy of magnetometer. The model shows the relation between direction error and distance to metallic component. (3)Model shadow fading in close proximity of RF transmitter. It builds a distance dependent shadow fading model. (4)Model based performance evaluation of hybrid localization. The test bench uses our models to simulate the hybrid localization data.

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Tyni, Elin, and Johanna Wikberg. "Classification of Wi-Fi Sensor Data for a Smarter City : Probabilistic Classification using Bayesian Statistics." Thesis, Umeå universitet, Institutionen för matematik och matematisk statistik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-159797.

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As cities are growing with an increasing number of residents, problems with the traffic such as congestion and larger emission arise. The city planners have challenges with making it as easy as possible for the residents to commute and in as large scale as possible to avoid vehicles. Before any improvements or reconstructions can be made, the traffic situation has to be mapped. The results from a probabilistic classification on Wi-Fi sensor data collected in an area in the southern part of Stockholm showed that some streets are more likely to be trafficked by cyclists than pedestrians while other streets showed the opposite. The goal of this thesis was to classify observations as either pedestrians or as cyclists. To do that, Bayesian statistics was applied to perform a classification. Results from a cluster analysis performed with K-means algorithm were used as prior information to a probabilistic classification model. To be able to validate the results from this unsupervised statistical learning problem, several model diagnostic methods were used. The final model passes all limits of what is considered to be a stable model and shows clear signs of convergence. The data was collected using Wi-Fi sensors which detect a device passing by when the device is searching the area for a network to connect to. This thesis will focus on data from three months. Using Wi-Fi sensors as a data collection method makes it possible to track a device. However, many manufacturers produce network interface controllers that generate randomized addresses when the device is connecting to a network, which makes it difficult to track the majority of the devices. Therefore, Wi-Fi sensor data could be seen as not suitable for this type of study. Hence it is suggested that other methods should be used in the future.
I takt med att städer växer med ökat antal invånare uppståar det problem i trafiken såsom trängsel och utsläpp av partiklar. Trafikplanerare ställs inför utmaningar i form av hur de kan underlätta pendling för invånarna och hur de, i så stor utsträckning som möjligt, kan minska fordon i tätorten. Innan potentiella förbättringar och ombyggnationer kan genomföras måste trafiken kartläggas. Resultatet från en sannolikhetsklassificering på Wi-Fi sensordata insamlat i ett område i södra delen av Stockholm visar att vissa gator är mer trafikerade av cyclister än fotgängare medan andra gator visar på motsatt föhållande. Resultatet ger en indikation på hur proportionen mellan de två grupperna kan se ut. Målet var att klassificera varje observation som antingen fotgängare eller cyklist. För att göra det har Bayesiansk statistik applicerats i form av en sannolikhetsklassifikation. Reslutatet från en klusteranalys genomförd med ”K-means clustering algorithm” användes som prior information till klassificeringsmodellen. För att kunna validera resultatet från detta ”unsupervised statistical learning” -problem, användes olika metoder för modelldiagnostik. Den valda modellen uppfyller alla krav för vad som anses vara rimligt f ̈or en stabil modell och visar tydliga tecken på konvergens. Data samlades in med Wi-Fi sensorer som upptäcker förbipasserande enheter som söker efter potentiella nätverk att koppla upp sig mot. Denna metod har visat sig inte vara den mest optimala, eftersom tillverkare idag producerar nätverkskort som genererar en slumpad adress varje gång en enhet försöker ansluta till ett nätverk. De slumpade adresserna gör det svårt att följa majoriteten av enheterna mellan sensorera, vilket gör denna typ av data olämplig för denna typ av studie. Därf ̈or föreslås att andra metoder för att samla in data används i framtiden.

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Lona, Daniel Grandin. "Implementação e análise de desempenho de sistemas rádio sobre fibra em redes WSN e Wi-Fi." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261430.

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Orientadores: Hugo Enrique Hernández Figueroa, Arismar Cerqueira Sodré Junior
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
Made available in DSpace on 2018-08-20T11:51:13Z (GMT). No. of bitstreams: 1 Lona_DanielGrandin_M.pdf: 5547359 bytes, checksum: 1dfde15018aecd3aee7c7be413e9c669 (MD5) Previous issue date: 2012
Resumo: O objetivo deste trabalho é avaliar a aplicabilidade da tecnologia Radio sobre Fibra (Radio over Fiber - RoF) em redes de sensores sem-fio (Wireless Sensor Networks - WSNs) e Wi-Fi. Inicialmente, realizou-se uma detalhada análise analítica de desempenho dos sistemas em função dos parâmetros típicos de equipamentos RoF, tais como: freqüência de operação, figura de ruído, ruído de intensidade relativa do laser, ruído shot do fotodetector, ruído térmico e modulação óptica. Os sistemas analisados foram então implementados em laboratório nas faixas de freqüência de 915 MHz e 2,4 GHz para WSN e Wi-Fi, respectivamente. Os parâmetros de desempenho medidos foram a indicação de intensidade de sinal recebida (Received Signal Strength Indication - RSSI), taxa de perda de pacotes (Packet Error Rate - PER) e vazão (Throughput)
Abstract: This works aims to evaluate the applicability of Radio over Fiber (RoF) technology in Wireless Sensor Networks (WSNs) and Wi-Fi networks. Initially, the system performance has been analytically evaluated as a function of diverse parameters from RoF pieces of equipment, such as: operation frequency, noise figure, relative intensity noise, shot noise of photodetector, thermal noise and optical modulation. Furthermore, the proposed RoF systems were experimentally implemented in laboratory at 915 MHz and 2.4 GHz bands for WSN and Wi-Fi, respectively. The performance metrics were Received Signal Strength Indication (RSSI), Packet Error Rate (PER) and throughput
Mestrado
Telecomunicações e Telemática
Mestre em Engenharia Elétrica

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Araujo, Maria S., Myron L. Moodie, Greg C. Willden, Ryan J. Thibodeaux, and Ben A. Abbott. "Integrating Wireless Sensor Technologies into Instrumentation and Telemetry Systems." International Foundation for Telemetering, 2010. http://hdl.handle.net/10150/605939.

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ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California
Recent technological advancements in low-power, low-cost, small-footprint embedded processors, sensors, and radios are resulting in the very rapid growth of wireless sensor network deployments. Wireless sensor networks merge the scalability and distributed nature of networked systems with the size and energy constraints of remote embedded systems. With the ever increasing need to develop less intrusive, more scalable solutions for instrumentation systems, wireless sensor technologies present several benefits. They largely eliminate the need for power and network wiring, thus potentially reducing cost, weight, and deployment time; their modularity provides the flexibility to rapidly change instrumentation configurations and the capability to increase the coverage of an instrumentation system. While the benefits are exciting and varied, as with any emerging technology, many challenges need to be overcome before wireless sensor networks can be effectively and successfully deployed in instrumentation applications, including throughput, latency, power management, electromagnetic interference (EMI), and band utilization considerations. This paper describes some approaches to addressing these challenges and achieving a useful system.

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Kumarasiri, Nuwan Rajika. "Development of Novel Algorithms for Localization in Wireless Sensor Networks." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1415717194.

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20

Hjelmberg, Eric, and Henrik Rowell. "Persondetektering i inomhusmiljö med enkla sensorer." Thesis, Linköpings universitet, Datorteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122908.

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Denna rapport syftar till att beskriva arbetet kring att kunna detektera närvaro i ett rum medhjälp av så enkla sensorer som möjligt, kopplade till en Arduino. Samtidigt som detta skerså används också systemet till att med samma sensorer visa klimatet i rummet. Läsaren fåren inblick i problematiken med att detektera människor samt inom funktionen av de valdasensorerna. Utöver detta studeras energiförbrukningen i systemet. Rapportenmynnar ut i enslutsats där en procentuell chans för närvaro presenteras via en internetuppkoppling medhjälp av en omfattande testning av sensorernas beteende.

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Jonsson, Tobias, and Gabriel Acquaye. "Application of IEEE 802.15.4 for home network." Thesis, Jönköping University, Jönköping University, JTH, Computer and Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-6545.

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To implement a utility wireless sensor network, investigation of different wireless protocols has been performed. The protocols are Bluetooth, Wi-Fi, IEEE 802.15.4 and Zigbee. Consecutively literature studies have made it comprehensible to understand the function of the protocols that are suitable for development of wireless sensor networks. The importance of low cost, low power, reliable and high-quality properties for long distances are significant. IEEE 802.15.4 and Zigbee protocol are proper to implement as a wireless sensor network.

To reduce the human efforts in the configuration of the system, a comfortable method is implemented to facilitate the procedure. The applied method is based on an automatic configuration of the system. The configuration and the decision taking are implemented in the software. The system is designed to avoid interference to other wireless networks with the possibilities of reconfiguration.

A uniform hardware and software design with separate functions of the system decided by a subsequent command for configuration is preferable. This imposes an advantage that increases the flexible potential of the system when a uniform solution is implemented.

To support the basic communication principles and control of the system, a buffer implementation has been introduced. The functionality of decision taking is distributed, configured by system commands from the host system. Detecting of system commands requires a properly operating buffer management. In consideration to the power consumption in reference to battery utilizations, the settings of RF-module and microcontroller have a powerful impact to reduce the power consumption. All possibilities of hibernates and avoidance of unnecessarily transmitting, should be deactivated to minimize the power consumption.

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Yao, Fang. "Interference mitigation strategy design and applications for wireless sensor networks." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/7193.

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The Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 standard presents a very useful technology for implementing low-cost, low-power, wireless sensor networks. Its main focus, which is to applications requiring simple wireless connectivity with relaxed throughout and latency requirements, makes it suitable for connecting devices that have not been networked, such as industrial and control instrumentation equipments, agricultural equipments, vehicular equipments, and home appliances. Its usage of the license-free 2.4 GHz frequency band makes the technique successful for fast and worldwide market deployments. However, concerns about interference have arisen due to the presence of other wireless technologies using the same spectrum. Although the IEEE 802.15.4 standard has provided some mechanisms, to enhance capability to coexist with other wireless devices operating on the same frequency band, including Carrier Sensor Multiple Access (CSMA), Clear Channel Assessment (CCA), channel alignment, and low duty cycle, it is essential to design and implement adjustable mechanisms for an IEEE 802.15.4 based system integrated into a practical application to deal with interference which changes randomly over time. Among the potential interfering systems (Wi-Fi, Bluetooth, cordless phones, microwave ovens, wireless headsets, etc) which work on the same Industrial, Scientific, and Medical (ISM) frequency band, Wi-Fi systems (IEEE 802.11 technique) have attracted most concerns because of their high transmission power and large deployment in both residential and office environments. This thesis aims to propose a methodology for IEEE 802.15.4 wireless systems to adopt proper adjustment in order to mitigate the effect of interference caused by IEEE 802.11 systems through energy detection, channel agility and data recovery. The contribution of this thesis consists of five parts. Firstly, a strategy is proposed to enable IEEE 802.15.4 systems to maintain normal communications using the means of consecutive transmissions, when the system s default mechanism of retransmission is insufficient to ensure successful rate due to the occurrence of Wi-Fi interference. Secondly, a novel strategy is proposed to use a feasible way for IEEE 802.15.4 systems to estimate the interference pattern, and accordingly adjust system parameters for the purpose of achieving optimized communication effectiveness during time of interference without relying on hardware changes and IEEE 802.15.4 protocol modifications. Thirdly, a data recovery mechanism is proposed for transport control to be applied for recovering lost data by associating with the proposed strategies to ensure the data integrity when IEEE 802.15.4 systems are suffering from interference. Fourthly, a practical case is studied to discuss how to design a sustainable system for home automation application constructed on the basis of IEEE 802.15.4 technique. Finally, a comprehensive design is proposed to enable the implementation of an interference mitigation strategy for IEEE 802.15.4 based ad hoc WSNs within a structure of building fire safety monitoring system. The proposed strategies and system designs are demonstrated mainly through theoretical analysis and experimental tests. The results obtained from the experimental tests have verified that the interference caused by an IEEE 802.11 system on an IEEE 802.15.4 system can be effectively mitigated through adjusting IEEE 802.15.4 system s parameters cooperating with interference pattern estimation. The proposed methods are suitable to be integrated into a system-level solution for an IEEE 802.15.4 system to deal with interference, which is also applicable to those wireless systems facing similar interference issues to enable the development of efficient mitigation strategies.

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Liu, Honggang. "Research and implementation of an indoor positioning algorithm." Thesis, Mittuniversitetet, Avdelningen för informationssystem och -teknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-32394.

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The goal of the Internet of Things’ sensing technology is to provide LBS(location-based services); a key technology is finding out how to positioning the sensing devices. For positioning outdoors, mature tech-nology such as GPS and cellular network location can be used. There is little research about indoor positioning, and there is no finished product on the market. This paper shows how to use both Wi-Fi and ZigBee signal for position-ing; Wi-Fi to find the area position and ZigBee to find the coordinate position. The main contribution of this paper is described in the follow-ing: This paper will present an algorithm using kNN on a Wi-Fi signal, as a way to find the location area of users. The GPS signal cannot be used indoors, but there are usually numerous Wi-Fi signals, that can be used for indoor positioning. In this design, to build a dataset containing the number of locations and the Wi-Fi signal strength list of each location. When indoor positioning is needed, the KNN algorithm is used to compare the user’s Wi-Fi signal strength with the dataset and find the location number. When precise positioning is needed, the ZigBee signal should be used. In this paper two different methods for precise positioning in are used, one is an improved algorithm of triangle centroid algorithm where the positioning accuracy depends on the number of anchor points and the interval of each point. The other method is the neural network method. This method could give stable result with only four anchor points. Finally, there is a comparison of the methods mentioned in this paper : the Wi-Fi fingerprint method, the ZigBee triangle centroid algorithm, and neural network method.

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Shala, Ubejd, and Angel Rodriguez. "Indoor Positioning using Sensor-fusion in Android Devices." Thesis, Högskolan Kristianstad, Sektionen för hälsa och samhälle, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-8869.

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This project examines the level of accuracy that can be achieved in precision positioning by using built-in sensors in an Android smartphone. The project is focused in estimating the position of the phone inside a building where the GPS signal is bad or unavailable. The approach is sensor-fusion: by using data from the device’s different sensors, such as accelerometer, gyroscope and wireless adapter, the position is determined. The results show that the technique is promising for future handheld indoor navigation systems that can be used in malls, museums, large office buildings, hospitals, etc.

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Maudet, Sébastien. "Analyse et modélisation énergétiques des réseaux de communications pour l’IoT." Electronic Thesis or Diss., Nantes Université, 2024. http://www.theses.fr/2024NANU4002.

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L’IoT est un concept innovant qui permet à des objets d’échanger des informations à travers des réseaux de communications. Ces objets sont généralement déployés avec des ressources énergétiques limitées et les protocoles de communications pour l’IoT doivent tenir compte de ces contraintes. Dans cette thèse, nous avons analysé et modélisé la consommation énergétique de deux des protocoles de communication les plus en vue de l’IoT. Dans un premier temps, nous nous sommes intéressés au Wi-Fi HaLow. Après une présentation descriptive de ce protocole et de ses mécanismes, ses performances ont été étudiées et qualifiées. Des campagnes de mesures ont montré son bon comportement en termes de portée, de débit et de latence. L’analyse du protocole ainsi que des mesures de l’énergie consommée sur du matériel ont permis d’établir un premier modèle de consommation. Ce dernier tient compte des échanges nécessaires à l’établissement d’une communication. Le modèle a ensuite été affiné pour obtenir une modélisation basée sur une chaîne de Markov absorbante qui prend en compte l’environnement et la densité du réseau. Cette étude permet de valider l’utilisation de cette technologie dans différents domaines de l’IoT. Dans un second temps, nous nous sommes intéressés au protocole LoRaWAN. Des mesures de l’énergie consommée sur du matériel ont permis de proposer un nouveau modèle de consommation énergétique qui prend en compte l’environnement du nœud (retransmissions, erreurs et collisions). Finalement, une comparaison des métriques et de la consommation énergétique de ces deux protocoles a été réalisée, afin d’ouvrir une discussion sur les perspectives d’utilisation selon des cas d’usage
IoT is an innovative concept that enables objects to exchange data over communications networks. These objects are typically deployed with limited energy resources, and IoT communication protocols must take these constraints into account. In this thesis, we analyzed and modeled the energy consumption of two of the most prominent IoT communication protocols. First, we focused on Wi-Fi HaLow. After a descriptive presentation of this protocol and its mechanisms, performance was studied and characterized. Measurement campaigns showed that it performs well in terms of range, throughput and latency. Analysis of the protocol and measurements of the energy consumed on hardware have enabled us to establish an initial consumption model. This takes into account the exchanges required to establish a communication. The model was then refined to obtain a model based on an absorbing Markov chain that takes into account the environment and network density. This study validates the use of this technology in various IoT domains.We then turned our attention to the LoRaWAN protocol. Measurements of the energy consumed on hardware enabled us to propose a new energy consumption model that takes into account the node’s environment (retransmissions, errors and collisions). Finally, a comparison of the metrics and energy consumption of these two protocols was carried out, in order to open a discussion on the prospects for use cases

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Lagerhult, Christopher. "Kartbaserad inomhuspositionering med virtuella accesspunkter." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-25726.

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Det har gjorts mycket forskning kring Positioneringssystem för inomhusbruk då många applikationer och tjänster ärberoende eller kan förbättras av det. Trots detta finns idag ingen standard för hur positionering inomhus ska fungera.För de flesta utomhusmiljöer kan en modern mobiltelefons position erhållas med ett par meters precision via GPS. I eninomhusmiljö sjunker signalen drastiskt och en precis position är svår att uppskatta. En väl etablerad teknik är Wi-Fioch kan med fördel användas då de flesta inomhusmiljöer idag redan har Wi-Fi accesspunkter installerade. Då enmottagare erhåller en signal från en accesspunkt kan distansen dem emellan uppskattas för att sedan uppskattapositionen med den matematiska tillämpningen trilateration. Då de flesta idag äger en mobiltelefon kan mobilen ageramottagare och tekniken kan således vara tillgänglig för alla.Bidraget med examensarbetet är en undersökning av den effekt virtuella accesspunkter har på ett positioneringssystemdär en trilaterationsbaserad lösning använts på Wi-Fi-signaler över både 2.4Ghz samt 5Ghz bandet i kombination med ett partikelfilter. Vidare kommer en karta nyttjas i ett försök att öka precisionen genom att skapa restriktioner för hurpositioneringen får röra sig. Resultatet visade att nyttjandet av virtuella accesspunkter ökade precisionen med drygt 10 procent och den valda kartlösningen med nästan 20 procent.
A lot of research has been made regarding indoor positioning since many applications and services are dependent or canbe improved by it. Despite this, no standard has been set for indoor positioning system concerning the best approach. Inoutdoor environments most modern smart phones can be used to estimate their position using the GPS. Indoors this isnot the case since the received signal strength is decreased drastically. A well-established technique is however Wi-Fiwhich promotes the use of it. When a receiver acquires a signal from a Wi-Fi access point the distance between them canbe estimated. Three or more known distances enables the receiver to calculate its position using a mathematicalapproach called trilateration. With the smart phone acting as the receiver, the approach is enabled for everyone.The contribution of this thesis is an investigation of the effect of using virtual access points. This will be tested in atrilateration based positioning system using both the 2.4Ghz and 5Ghz frequency band in combination with a particlefilter. In an attempt to increase the precision a map will be added into the algorithm with the intention of restricting usermovements. The attained result shows that the use of virtual access points decreased the position estimation error by approximately 10 percent, and the implemented map solution by merely 20 percent.

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Pizúr, Lukáš. "Robotická ruka." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-399489.

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The aim of this work is to design a robotic hand, which will be controlled by wireless Wi-Fi, will be equipped with a camera and for easier operation will be designed control glove. The first part of the thesis is a theoretical analysis, various variants of sensors are described, which can be used for motion detection, each drive units and their control. Next chapters are focused on used electronic modules and microcontrollers. The second part is practical and is focused on the mechanical design of a five-finger robotic hand and fixing to a robotic arm. Also described is the control electronics of the entire robotic hand and the programmed firmware. Next, the design and implementation of the control glove is described. The last chapter describes the programmed application for the Android operating system.

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Teófilo, Ana Filipa Frazão de Almeida. "Low-Cost Indoor Localisation Based on Inertial Sensors, Wi-Fi and Sound." Master's thesis, 2021. http://hdl.handle.net/10362/130418.

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The average life expectancy has been increasing in the last decades, creating the need for new technologies to improve the quality of life of the elderly. In the Ambient Assisted Living scope, indoor location systems emerged as a promising technology capable of sup porting the elderly, providing them a safer environment to live in, and promoting their autonomy. Current indoor location technologies are divided into two categories, depend ing on their need for additional infrastructure. Infrastructure-based solutions require expensive deployment and maintenance. On the other hand, most infrastructure-free systems rely on a single source of information, being highly dependent on its availability. Such systems will hardly be deployed in real-life scenarios, as they cannot handle the absence of their source of information. An efficient solution must, thus, guarantee the continuous indoor positioning of the elderly. This work proposes a new room-level low-cost indoor location algorithm. It relies on three information sources: inertial sensors, to reconstruct users’ trajectories; environ mental sound, to exploit the unique characteristics of each home division; and Wi-Fi, to estimate the distance to the Access Point in the neighbourhood. Two data collection protocols were designed to resemble a real living scenario, and a data processing stage was applied to the collected data. Then, each source was used to train individual Ma chine Learning (including Deep Learning) algorithms to identify room-level positions. As each source provides different information to the classification, the data were merged to produce a more robust localization. Three data fusion approaches (input-level, early, and late fusion) were implemented for this goal, providing a final output containing complementary contributions from all data sources. Experimental results show that the performance improved when more than one source was used, attaining a weighted F1-score of 81.8% in the localization between seven home divisions. In conclusion, the evaluation of the developed algorithm shows that it can achieve accurate room-level indoor localization, being, thus, suitable to be applied in Ambient Assisted Living scenarios.
O aumento da esperança média de vida nas últimas décadas, criou a necessidade de desenvolvimento de tecnologias que permitam melhorar a qualidade de vida dos idosos. No âmbito da Assistência à Autonomia no Domicílio, sistemas de localização indoor têm emergido como uma tecnologia promissora capaz de acompanhar os idosos e as suas atividades, proporcionando-lhes um ambiente seguro e promovendo a sua autonomia. As tecnologias de localização indoor atuais podem ser divididas em duas categorias, aquelas que necessitam de infrastruturas adicionais e aquelas que não. Sistemas dependentes de infrastrutura necessitam de implementação e manutenção que são muitas vezes dispendiosas. Por outro lado, a maioria das soluções que não requerem infrastrutura, dependem de apenas uma fonte de informação, sendo crucial a sua disponibilidade. Um sistema que não consegue lidar com a falta de informação de um sensor dificilmente será implementado em cenários reais. Uma solução eficiente deverá assim garantir o acompanhamento contínuo dos idosos. A solução proposta consiste no desenvolvimento de um algoritmo de localização indoor de baixo custo, baseando-se nas seguintes fontes de informação: sensores inerciais, capazes de reconstruir a trajetória do utilizador; som, explorando as características dis tintas de cada divisão da casa; e Wi-Fi, responsável pela estimativa da distância entre o ponto de acesso e o smartphone. Cada fonte sensorial, extraída dos sensores incorpora dos no dispositivo, foi, numa primeira abordagem, individualmente otimizada através de algoritmos de Machine Learning (incluindo Deep Learning). Como os dados das diversas fontes contêm informação diferente acerca das mesmas características do sistema, a sua fusão torna a classificação mais informada e robusta. Com este objetivo, foram implementadas três abordagens de fusão de dados (input data, early and late fusion), fornecendo um resultado final derivado de contribuições complementares de todas as fontes de dados. Os resultados experimentais mostram que o desempenho do algoritmo desenvolvido melhorou com a inclusão de informação multi-sensor, alcançando um valor para F1- score de 81.8% na distinção entre sete divisões domésticas. Concluindo, o algoritmo de localização indoor, combinando informações de três fontes diferentes através de métodos de fusão de dados, alcançou uma localização room-level e está apto para ser aplicado num cenário de Assistência à Autonomia no Domicílio.

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Liao, Chung-Wei, and 廖仲偉. "The Study of Building Wi-Fi Radio Map for Indoor Positioning System with Smartphone Sensors Assisted." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/89099908085609214932.

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碩士
中原大學
通訊工程碩士學位學程
102
Mobile communications and Internet have become one of the most important services nowadays. Most mobile devices, such as cell phone, PDA, and laptop computer, equipped with the WiFi, GPS, and Bluetooth as their standard equipment, and people have got used to use mobile services in their daily life. One interesting service is WiFi-based indoor positioning system (IPS) that attracts many researchers devote their effort to it. Many researches in IPS determines the user location by the method of scene analysis. However, this method need to collect the AP’s RSSI in many place in the building (called SPs) beforehand to build a WiFi radio map database, and that costs a lot of time when doing the sampling. Meanwhile, it also needs resampling very often in order to keep the accuracy of the positioning result. In this thesis, we design and test a fast build algorithm for collecting those SPs. The Android smartphone and their build-in motion sensors were used to help to collect the AP’s RSSI. The use scenario is stated as follows: A user who takes a smartphone and walks straight in a building corridor. We use the motion sensor to determine the steps while walking and collect the AP’s RSSI in every steps. The method completes the sampling work in a walking period where shorten the time for sampling a lot. This thesis also compare the fast build algorithm with the tradition method from the positioning accuracy point of view. Experiments show that there is no significant different between them.

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MILANI, ILEANA. "Wi-Fi sensing: fusion of non-cooperative and device-based RF sensors for short-range localization." Doctoral thesis, 2020. http://hdl.handle.net/11573/1378688.

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Through the years, target localization has captured the attention of both academic and industrial worlds, thanks to the huge amount of applications which require the knowledge of the position information. Several works can be found on this topic, where the target localization has been addressed in different ways, depending on the type of target, the specific application and the surrounding scenario. The main goal of this thesis is the definition of innovative methodologies able to solve the problem of the localization of human targets and small objects in local area environments in any operating conditions. In addition to the achievement of important improvements in positioning accuracy, we are also interested in performing the localization for the entire observation time where the target stays in the area of interest. To achieve this result, in this work we decided to propose the joint use of different positioning techniques, based on their fusion in a unified system. The advantage of this fusion lies in the possibility of compensating for the intrinsic limitations of each proposed methodology, especially when complementary techniques are employed. Two different sensors are considered in this work. Both exploit the Wi-Fi transmissions, based on the IEEE 802.11 Standard, therefore also the same receiver can be employed to receive measurements and information about the target present in the area of interest from multiple sensors, without increasing the complexity of the receiving system. Specifically, the first candidate to be used is the Passive Bistatic Radar (PBR) that exploits the Access Point (AP) as illuminator of opportunity. Due to the possibility to obtain the human target position without the necessity for the target to carry a device, this technique can be inserted into the group of the “Device-free localization” methodologies. It makes the WiFi-based passive radar attractive for local area surveillance and monitoring applications, especially where the targets cannot be assumed to be cooperative, as in typical security applications. With reference to the second sensor, the Passive Source Location (PSL) is another possible strategy to estimate the target position. In contrast to the PBR, this is a device-based technique that uses the device transmissions to perform the localization of the specific target. Considering the characteristics of the proposed strategies, it is evident that they present complementary aspects. We can take advantage from this complementarity in several ways. Firstly, due to the Time Division Multiple Access (TDMA) approach used in the Wi-Fi Standard, devices and AP cannot transmit simultaneously, so we can compensate for the lack of signals from one sensor with the measures estimated by the other one. Secondly, we can use the device-based strategy when the target is stationary, and the Passive Radar cannot estimate its position because of the cancellation stage performed during the processing. On the other hand, the Passive Radar is necessary when the target does not carry an active mobile device, or it does not want to be localized (surveillance and monitoring activities). Finally, we can discriminate even very closely spaced target (if both carry an active mobile device) thanks to the possibility to read the MAC Address written into the packets of their devices. The first part of this thesis is dedicated to the characterization of the single sensors, based on the description of the measurement extraction and the evaluation of the related positioning techniques. With respect to the measurement extraction, the PBR provides the target position through the combination of different sets of measures as range/Doppler/Angle of Arrival (AoA). For the PSL, the Time Difference of Arrival (TDoA) and the AoA can be exploited for the same purpose. Since the properties of the PBR have been extensively defined by our research group in the past, in this work more attention has been dedicated to the PSL description. In particular, proper techniques for measurement estimation are reviewed and innovative techniques for TDoA estimation of the PSL sensor are proposed, which provide improved performance with respect to existing techniques. The accuracies achieved with different positioning techniques exploiting several combinations of the estimated measurements are then evaluated. The results show that in short range applications it is desirable to use only AoA measurements, if possible. After the characterization of the sensors, the localization performance of the two techniques are analyzed and compared. This analysis has shown both the effectiveness of the two sensors in target localization and their inherent limitations. In particular, we have studied the relationship between data traffic conditions and performance, and we have seen that it is strictly linked to the number of data available for the estimation of the measures of interest. In addition, the complementarity of the two methodologies has been demonstrated through the evaluation on experimental data acquired in appropriate measurement campaigns, in different network traffic conditions. In this phase, a tracking stage has not been performed. In order to improve the localization performance and carry out the desired sensor fusion, the second part of the thesis has been dedicated to the definition of innovative techniques for target tracking which exploit the characteristics of the employed sensors. Specifically, a new Sensor Fusion tracking filter is proposed. It uses a modified version of the Interacting Multiple Model (IMM) approach, where a Modified Innovation (MI) is introduced, together with Data Fusion techniques. In particular, in this strategy the information related to the presence or absence of the PBR estimates is used to help the choice between the employed filters, in order to improve the localization performance of human targets in the typical “stop & go” motion scenario. The performance of the proposed strategy has been evaluated on both simulated and experimental data. The performance has shown that the IMM-MI outperforms the other strategies, since it provides the best performance in terms of positioning accuracy, target motion recognition capability and percentage of acquisition time covered by this strategy.

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Couceiro, Francisco Monteiro Santos Brás. "SmartLocator - Indoor Human Localization using a Smartphone." Master's thesis, 2017. http://hdl.handle.net/10316/83192.

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Dissertação de Mestrado Integrado em Engenharia Electrotécnica e de Computadores apresentada à Faculdade de Ciências e Tecnologia
A sensibilidade ao contexto é de elevada importância para serviços prestados por plataformas digitais de computação ubíqua, onde a localização é uma das dimensões fundamentais desse contexto. Há mais de 2.3 mil milhões de utilizadores de smartphones. Juntamente com a crescente onda de partilha social, há mais utilizadores da internet que usam dispositivos móveis do que computadores pessoais. A massificação do uso do smartphone criou a necessidade emergente de adquirir informação de localização nestes dispositivos. Seja para fornecer conteúdos curados aos utilizadores ou para sistemas de alerta/monitorização, há um novo mercado por explorar.Conseguir estimar a localização de um dispositivo foi a grande motivação para a criação do GPS - Global Positioning System - que é a principal tecnologia de localização em ambientes exteriores utilizada para navegação, tanto de automóveis como de aviões. Porém, em locais interiores, a falta de precisão deste método tem favorecido o aparecimento de soluções de localização alternativas.Por todo o mundo há já uma enorme infraestrutura de pontos de rede Wi-Fi disponíveis, o que aliado aos recentes avanços na qualidade dos sensores embebidos em dispositivos móveis, faz desta plataforma o foco actual da computação pervasiva.O SmartLocator procura localizar humanos através de um smartphone, em ambientes onde exista uma infraestrutura Wi-Fi. É proposto um algoritmo de localização indoor baseado na fusão de dados fornecidos pela rede Wi-Fi e pelos sensores inerciais disponíveis no dispositivo móvel. A criação a priori de um mapa de potência de sinais de rádio emitidos pelos access points existentes, permite numa fase a posteriori a estimação da posição geográfica de um smartphone. Esta técnica chama-se Fingerprinting. Contudo, a variabilidade da infraestrutura Wi-Fi e da potência dos sinais recebida, devido a problemas de propagação comuns, influenciam a precisão deste método. Usando dados provenientes dos sensores inerciais é possível estimar deslocações relativas a um ponto cuja localização seja conhecida, ainda que com erros cumulativos elevados. Esta técnica é conhecida por Dead Reckoning. A fusão destas duas fontes de informação aumenta a precisão de localização.
Context awareness is very important for services provided by digital platforms of ubiquitous computing, being localization one of the fundamental dimensions in defining the context. There are currently more than 2.3 billion smartphone users. With the growing trend of social sharing, there are more internet users using mobile devices than personal computers. The massification of smartphone adoption has created the emerging need to acquire their users localization information. Whether it is to deliver cured content to users or to create surveillance systems, there is a new market to explore.Being able to estimate the position of a device was the main motivation behind the development of GPS - Global Positioning System - which is the mainstream localization technology in outdoor environments used for navigation, of both cars and airplanes. However, in indoor environments, this method lack of accuracy has led to the development of alternative localization solutions. There is already a vast infrastructure of Wi-Fi network points available across the globe, which coupled with recent developments in the quality of embedded sensors on mobile devices, make these platforms a focus of pervasive computing.The SmartLocator system offers a way to localize humans using a smartphone, in environments where a Wi-Fi infrastructure already exists. An algorithm based on the fusion of data provided by the Wi-Fi network and by the inertial sensors available on the mobile device is proposed. It is possible to estimate the position of a smartphone using a pre-populated database of received signal strength from the existing access points. This technique is called Fingerprinting. However, the variability of the Wi-Fi infrastructure and in received signals strength, due to common propagation issues, influence the precision of this method. By using data obtained from the embedded inertial sensors it is possible to continuously track displacements from a known initial position, possibly with high cumulative errors. This technique is known as Dead Reckoning. The fusion of these two sources of data improves the localization accuracy.

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Lino, David Bastos da Silva. "A data collection mechanism for Wi-Fi based Underground sensor Networks." Master's thesis, 2014. https://repositorio-aberto.up.pt/handle/10216/76312.

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Lino, David Bastos da Silva. "A data collection mechanism for Wi-Fi based Underground sensor Networks." Dissertação, 2014. https://repositorio-aberto.up.pt/handle/10216/76312.

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34

Wu, Chung-Hsien, and 吳仲賢. "Intelligent Infant Monitoring System Based on Wi-Fi Wireless Sensor Network." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/29m9dx.

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碩士
國立虎尾科技大學
電機工程系碩士班
104
The intelligent monitoring is the mainstream development of the future automation and networking technology. This thesis presents an infant care system based on Wi-Fi wireless network. This system combines a variety of sensor to detect status of the cradles and the infants. The data will be transmitted to the home server through Wi-Fi wireless transmission module, and establishes a database and users are able to interface with the server. A home based remote server enables remote monitoring and control of smart cradle. The status and information on all monitored appliances are stored in the remote server. Users are allowed to use their electronic devices such as smartphones, tablets to do remote control. Thus, this infant care system brings convenience and advantage to the users of this system.

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35

Chen, Yi-Chao, and 陳奕超. "Sensor-Assisted Wi-Fi Indoor Location System for Adapting to Environmental Dynamics." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/19336439839007819433.

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碩士
國立臺灣大學
資訊工程學研究所
94
Wi-Fi based indoor location systems have been shown to be both cost-effective and accurate, since they can attain meter-level positional accuracy by using existing Wi-Fi infrastructure in the environment. However, two major technical challenges persist for current Wi-Fi based location systems: instability in positional accuracy due to changing environment dynamics, and the need for manual online calibration during site survey. To address these two challenges, three environment factors (doors, humidity, and human cluster) that can interfere with radio signals and cause positional inaccuracy in the Wi-Fi location systems are identified. Then, we propose a sensor-assisted adaptation method that employs environment and proximity sensors to adapt the location systems automatically to the changing environment dynamics. In addition, a collaborative method is applied to leverage more accurate location information from nearby neighbor nodes to enhance the positional accuracy of a human cluster. Experiments were performed on the sensor-assisted adaptation and collaboration methods. The experimental results show that our enhancement can avoid adverse reduction (43.7% ~ 236.6%) in positional accuracy that can often occur in conventional non-adaptive & non-collaborative methods under changing environment dynamics.

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Lin, Tzu-Chiao, and 林子喬. "Wi-Fi Direct Applied to Node of Wireless Sensor Network and Realization." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/23391851194258850628.

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Chen, Hung-Ting, and 陳弘庭. "Design of Intelligent Multi-Sensor Control System Based on ZigBee and Wi-Fi Wireless Sensor Network." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/33461552648310861365.

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碩士
中華科技大學
電子工程研究所碩士班
103
In recent years, the home environment has seen a new form of communication in which users can to increase the interaction of sensors within the home for the purpose of smart home design. In this paper, we present our framework of smart home applications. We show that by increasing interactivity for the design of user and the environment interact through various wisdom of the sensors. A ZigBee based smart home system and Wi-Fi network integrated through a wireless sensor network to smartphone. There has been user experience into the conscious control of sensor in the past. We will transform this effectiveness into daily life activity, to effect that the sensors confirm with unexpectations. We also use smartphones together with various wisdom of the sensor, to enhance the quality of life and fun.

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Ming-HuangChen and 陳明皇. "A Monitoring System Development for Machine Tool Factory Using Wi-Fi Wireless Sensor Network Technology." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/8q285v.

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碩士
國立成功大學
製造資訊與系統研究所碩博士班
101
Machine tool monitoring systems have a wiring plant inconvenience and high cost of inadequate transfer rate is too slow. This research is combines Wi-Fi sensing module with low cost and high transmission rate of the advantages of establishing a remote monitoring system. In experimental models, for example machine tools, with Wi-Fi modules and embedded systems established based on Wi-Fi wireless Internet technology tools of factory monitoring system. Main contributions are as follows: 1.To realize the performance, this research designs a high response dynamic load measurement module, to catch information such as current, voltage, and vibration, and prove this system can integrate single module and catch those signals inside the machine tool from this wireless sensor network monitoring system, by high speed of transmission data through wireless sensor network, store data in the cloud server, so that it can be real-time and high response remote monitoring system which is sensing signals inside the machines. 2.Load cell amplifier on high response dynamic weight measurement module is low noise processing. Low noise amplifier, high precision ADC, filter, DSP and surrounding circuit built this module. This amplifier can adjust measuring range by adjusting amplifier gain, applying on different objects. 3.Monitoring system by using ASP.NET to construct a website, SQL Server 2008 as Database to save data, and multiple sensors such as temperature, humidity, vibration, noise, gas, and so on, to built a wireless sensor network by Wi-Fi on machine tool factory, it realizes a real-time and remote monitoring platform to show those information about high frequency response on vibration and noise and etc.. With the help of Cloud servers, saving that information from sensors on them, so that managers and engineers can review that information from website to do machine management and make emergent decisions real-time.

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Lin, Wu-Nan, and 林武男. "Use Wi-Fi Wireless Sensor Networks to Achieve Location-Based Services for Information Service Platform." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/65874981941172148594.

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碩士
樹德科技大學
資訊工程學系
97
Recent advances in wireless sensor technology and portable devices give rise to the term: Location-Based Service (LBS). With LBS higher precision of positioning, Location-Based Service (LBS), and other applications under LBS service platform are provided for the end-user. In order to improve the application of LBS, this study employed the Wireless Sensor Network developed by Cisco Unified Wireless Network (UWN) as the technology for indoor positioning and designed as well as modulized Services Gateway Server (SGS). In addition, double positioning to increase accuracy, a mobile device supporting IEEE 802.11 standard and integration of information generated by Service Provider using Web Service were studied. It is anticipated that the end-user is able to achieve LBS in the campus simply with a smart device supporting IEEE 802.11 standard combined with indoor positioning technology of Cisco UWN via access to wireless internet.

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Perdigão, André David Távora. "Infraestrutura de comunicações e serviços para IoT em ambientes urbanos." Master's thesis, 2018. http://hdl.handle.net/10773/28301.

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Nos últimos anos têm sido criticados os testes das tecnologias apenas em simuladores, por não terem em conta as condicionantes da realidade e suas influências para os utilizadores em ambiente real. Tais críticas têm levado à realização de testes em ambientes reais, tendo, contudo, um efeito agravante que é a exigência de uma infraestrutura grande e cara, o que torna mais difícil aos investigadores e desenvolvedores o acesso às mesmas. Por vários motivos, incluindo os custos de desenvolvimento em ambientes reais, tem existido um aumento da diferença entre a tecnologia desenvolvida no momento e a tecnologia disponibilizada para o público em geral, o que gerou um crescente interesse em criar laboratórios em condições reais pelo mundo inteiro, chamados laboratórios vivos. Estes laboratórios têm por objetivo disponibilizar as tecnologias em desenvolvimento, fornecendo o acesso aos investigadores interessados, assim permitindo que sejam feitos testes e demonstrações nestas plataformas, obtendo resultados realísticos. Tal poderá acelerar a finalização destas tecnologias, ajudando a reduzir a diferença entre as tecnologias disponíveis e as tecnologias a serem desenvolvidas no momento. Este trabalho apresenta contribuições para o projeto PASMO, que vai fornecer uma plataforma que disponibiliza tecnologias recentes para testes e desenvolvimento. As contribuições apresentadas neste trabalho para a plataforma estão divididas em três partes, que são: planeamento, eletrónica e controlo de rede. A parte de planeamento consiste em decidir a localização dos equipamentos da plataforma, mas, como a plataforma tem de funcionar em diversas condições temporais, foi necessário a execução de vários testes que servem para verificar os limites das várias tecnologias escolhidas, de forma a garantir o bom funcionamento da plataforma mesmo em condições adversas. Assim sendo, neste trabalho foram feitos testes de LoRa e Wi-Fi, em que se obteve um alcance superior a 500 metros para o Wi-Fi, e um alcance de 100 metros para os sensores de estacionamento de LoRa testados. Com base nos resultados obtidos foram selecionadas algumas opções de localização dos dispositivos. A parte de eletrónica resume-se na criação de um sistema heartbeat, que controla se o equipamento da plataforma está a funcionar normalmente, e caso exista algum problema pode remover temporariamente a energia ao equipamento da plataforma de forma a obrigar a um reiniciar. Esse sistema, tem um circuito para controlar a energia fornecida aos equipamentos da plataforma, e além disso, o sistema heartbeat tem um dispositivo de processamento, que monitoriza um desses equipamentos e controla o circuito. Verificou-se que com a solução desenvolvida se consegue monitorizar um Access Point. Na parte controlo de rede foi feito um programa que consegue comunicar com cada um dos sistemas heartbeat, que consegue controlar cada um deles sem a necessidade da deslocação ao local do equipamento.
In recent years, it has been criticized to only test technologies at simulators, before being applied for everyone to use. Due to these critics, it is now necessary to test all technologies in real environment. However, some technologies require a large and expensive infrastructure, making it difficult for researchers to access. For some reasons, including the reasons above, there has been an increasing difference between the technologies used and the technologies in development. This generates a growing interest in creation of open living labs around the world. These laboratories are made to provide recent technologies, giving access to researchers interested in its development. Allowing test and demonstrations at these platforms for realistic results. This will help in finalizing the technologies, which will reduce the gap between available technologies and the technologies in development at the moment. This thesis presents some contributions made for the PASMO project, which will provide a platform where will be possible to test and develop some recent technologies. These contributions can be divided in three different parts: planning, electronic e network control. In the planning part it was discussed where the equipment will be deployed. To select the locations, it was necessary to tests the technologies used under different climatic conditions. These tests were made to know the limits of the technologies used, in order to guarantee that the platform works in adverse conditions. The tests were made on Wi-Fi and LoRa, and analysing the results obtained we concluded that the range of Wi-Fi is more than 500 meters and the range of LoRa parking sensors is 100 meters. Based on these results, some options were selected to the places of equipment. In the electronic part, it is the projection of a heartbeat system. This system will check if the platform equipment is operating normally. In case of problems, this system can temporarily remove the power of the equipment, to make a hard reset on the equipment. For this it was necessary to create a circuit to control the energy and a program to a microcontroller that will check the equipment and control the circuit. With the solution developed it was verified that an access point can be monitored. For the network control part, a program has been made that can communicate with each heartbeat system. With this program, the user can control and monitor each heartbeat system without having to go to the location of the equipment.
Mestrado em Engenharia Eletrónica e Telecomunicações

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Li, Chih-Mo, and 李致謀. "Enhance the Performance of Wireless Sensor Network by Using Dynamic Multi-Channel Hopping Mechanism for IEEE 802.15.4e TSCH Under the Wi-Fi Coexistence Environment." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/fz86g4.

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碩士
國立臺中教育大學
資訊工程學系
103
Recently, an increasing number of wireless network has been deployed and started to provide individualized services. Wireless communication network has gradually converged applications to heterogeneous wireless technology direction. There are a number of wireless communication technologies, such as WPAN (wireless personal area network, IEEE 802.15), WLAN (wireless local area network, IEEE 802.11), WMAN (wireless metropolitan area network, IEEE 802.16), WSN (wireless sensor networks, IEEE 802.15.4), 2G, 3G, WiMAX (Wireless Metropolitan Area network, IEEE 802.11e) and the recently 4G technology (LTE, Long Term Evolution) wireless communications network. These kinds of wireless communication network environment called heterogeneous communication networks. IEEE 802.15.4 is commonly used the ISM band is the range of 2.400 ~ 2.4835 MHz radio frequency, and the IEEE 802.11 will overlap with each other. Therefore, in the MAC layer, IEEE 802.15.4e has proposed a Time Slotted Channel Hopping (TSCH) for industrial wireless sensor networks. This technology was transmitting packet into time slots by different transmitting channel. The advantage of TSCH is reducing the co-channel interference to meets the demand of industrial wireless sensor networks. In this thesis, we analysis the impact of IEEE 802.15.4e network under the IEEE 802.11 coexistence environment. A “D-MCHM IEEE 802.15.4e TSCH” has been proposed in this research to enhance the transmission probability for the IEEE 802.15.4e network. Experimental results show the proposed mechanism could improve the Packets Delivery Rate (PDR) effectively under the IEEE 802.11 coexistence environment.

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Salah, Mohamed Ben. "Agricultural LoRA sensor network applied to soil moisture monitoring for fertigation-based production." Master's thesis, 2021. http://hdl.handle.net/10198/24778.

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Mestrado de dupla diplomação com a Université Libre de Tunis
The global water crisis is one of the serious threats that human being is facing and especially farmers due to a variety of environment issues. This growing trend of water scarcity led to the existence of the efficiency of irrigation systems for agricultural proposes using electronic sensors and performance systems to precise the amount of water for the growth of plants. However, currently, some automation attempts led to a sub-optimal solution as they do not take into account the vegetative development state of the plants and the small differences in environmental conditions present inside greenhouses. In this project, the work is based on developping a monitoring system based on measurement nodes for real-time monitoring temperature, and humidity. Open-source hardware and sensors was use to create the measurement nodes using LoRa WAN a wireless sensor network. The aim of this work is to create a network of sensors inside a greenhouse in order to obtain regularly updated information. The data is going to be useful since is easy to utilize by the farmers directly from a platform. Measurement node, communicating in real-time through LoRa, will transmit data to the gateway which will then be displayed on a dashboard.
The classic internet is a global system of interconnected computer networks which carries a vast range of information resources and services in which HTTP (Hypertext Transfer Protocol) is the first protocol used to transfer hypertext data, from server to the end customer. The classic internet is thus based on the internet of data. On the other hand, the internet of things (IoT), is a new tool for connectivity and mobility, that is to transform business and is helpful in daily life to connect objects. Nowadays, common objects become active and intelligent, integrating seamlessly into a global network and can produce and exchange useful data without the intervention of humans. It’s a network of networks that allows us to identify and communicate digitally with the physical and virtual world. In the near future, the IoT will cover a wide range of applications in our daily life. The world is experiencing a huge increase of intelligent objects, that has led cloud service companies to make platforms known as the Internet of things platforms (IoT platform), which contain services, statistics, libraries, analyses that facilitate communication as well as accelerate and reduce the cost of product development of IoT applications.

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Costa, João Luís Ramos da. "Indústria 4.0 na MCM: projeto e conceção de um módulo de pesagem." Master's thesis, 2018. http://hdl.handle.net/10773/26050.

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Considera-se que a presente tese não focou um problema singular, mas sim, a melhoria ou redução do custo de fabrico de máquinas já existentes, fabricadas pela empresa MCM-eletronic solutions, tendo por vista projetar uma nova, com o material que foi sendo desenvolvido em parceria com a empresa. Para este efeito, foi elaborado um módulo de pesagem possível de ser compar ável com os módulos anteriormente concebidos pela empresa e, consequentemente, testado e usado em condições semelhantes. A par do módulo, foi elaborado software, de modo a facilitar uma futura implementação do mesmo numa pesadora não combinatória e num calibrador hortofrutícola. Em simultâneo houve a tentativa de adicionar algum tipo de inovação ao material existente, integrando comunicações sem os e acrescentando possibilidades no campo da acessibilidade, tentando apresentar uma solução inovadora mas também normalizada, com métodos usados na indústria moderna
It is considered that the present thesis did not focus on a single problem, but rather on improving or reducing the cost of manufacturing of existing machines, already manufactured by the company MCM-eletronic solutions, with a view to designing a new one, with the material that was developed in partnership with the company. For this purpose, a weighing module has been developed which is comparable to previous modules designed by the company and, therefore, tested and used in similar circumstances. At the same time, there was an attempt to add some kind of innovation to the existing material, including wireless communications and adding possibilities in the eld of accessibility, trying to present an innovative but also standardized solution with methods used in modern industry
Mestrado em Engenharia Mecânica

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Нікітішина, Анастасія Олександрівна. "Дослідження та розробка пристрою для моніторингу повітряного середовища." Магістерська робота, 2020. https://dspace.znu.edu.ua/jspui/handle/12345/2273.

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Нікітішина А. О. Дослідження та розробка пристрою для моніторингу повітряного середовища : кваліфікаційна робота магістра спеціальності 153 "Мікро- та наносистемна техніка" / наук. керівник О. Ю. Небеснюк. Запоріжжя : ЗНУ, 2020. 89 с.
UA : Розроблена фізична модель пристрою детектування вуглекислого газу на основі мікроконтролера ATmega328P, що дозволяє предавати отримані результати на мобільні телефони за допомогою мережевої технології Wi-Fi.
EN : A physical model of the carbon dioxide detection device has been developed based on the ATmega328P microcontroller, which allows transmitting the obtained results to mobile phones using Wi-Fi network technology.

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Dissertations / Theses on the topic 'Wi-Fi Sensors'

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