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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The Design, Testing, and Analysis of a Constant Jammer for the Bluetooth Low Energy (BLE) Wireless Communication Protocol

Shintani, Aiku 01 June 2020 (has links) (PDF)
The decreasing cost of web-enabled smart devices utilizing embedded processors, sensors, and wireless communication hardware have created an optimal ecosystem for the Internet of Things (IoT). IEEE802.15.4, IEEE802.11ah, WirelessHART, ZigBee Smart Energy, Bluetooth (BT), and Bluetooth Low Energy (BLE) are amongst the most commonly used wireless standards for IoT systems. Each of these standards has tradeoffs concerning power consumption, range of communication, network formation, security, reliability, and ease of implementation. The most widely used standards for IoT are Bluetooth, BLE, and Zigbee. This paper discusses the vulnerabilities in the implementation of the PHY and link layers of BLE. The link layer defines the scheme for establishing a link between two devices. Scanning devices are able to establish communication with other devices that are sending advertising packets. These advertising packets are sent out in a deterministic fashion. The advertising channels for BLE, specified by the PHY layer, are Channels 37, 38, and 39, at center frequencies 2.402, 2.426, and 2.480 GHz, respectively. This scheme for establishing a connection seems to introduce an unintentional gap in the security of the protocol. Creating and transmitting tones with center frequencies corresponding to those of the advertising channels, a victim BLE device will be unable to establish a connection with another BLE device. Jamming a mesh network of BLE devices relies on this same concept. The proposed jamming system is an inexpensive one which utilizes the following hardware. Three individual synthesizers, a microcontroller (MCU), Wilkinson power combiner, power amplifier, and antenna, integrated on a single PCB, are used to transmit a 3-tone signal. Due to the unprecedented nature of the COVID-19 pandemic, necessary adjustments were made to the jammer system design. In the first modified jamming scheme, a single synthesizer evaluation board, power amplifier, and antenna, are used to transmit jamming tones in the form of a frequency hop. Limitations of the frequency hop approach necessitated a second modified scheme. In this second scheme a synthesizer and two Software Defined Radios (SDR), connected to a personal computer, continuously generate three individual jamming tones. The proposed jammer and the modified ones all classify as constant jammers as the transmission of jamming signals is continuous. Both modified jamming schemes are tested. The results of jamming using the second modified scheme validate the objective of simultaneous jamming of the advertising channels of BLE devices. The success of the modified scheme enables the original goal of creating a relatively inexpensive custom PCB for BLE advertising channel jamming. By exploiting the weakness of the BLE protocol, the hope is to have the governing body for Bluetooth, Bluetooth Special Interest Group (SIG), improve security for the future releases of BLE.
42

Evaluation of Angle of Arrival based positioning for keyless entry access control

Englund, Martin January 2018 (has links)
This thesis aims at evaluating a proposed interferometry Angle of Arrival method for Bluetooth Low Energy and investigating the feasibility of using it together with current technology in a keyless entry access control solution. The current technology is an evaluation kit from Texas Instrument that is used together with various types of antennae arranged in arrays. An in-depth look at it revealed that it does not implement the proposed Angle of Arrival method for Bluetooth Low Energy but the deviations are minor. Results obtained from tests with delay lines show enough accuracy for a keyless entry access control solution. However, none of the tested antenna types do. The work concludes that current technology cannot be used as a keyless entry access control solution due to strong antenna dependencies. Future work is thus proposed to be done on antenna development. / Detta arbete syftar till att utvärdera en förslagen interferometri Angle of Arrival-metod för Bluetooth Low Energy samt undersöka möjligheten att använda den tillsammans med nuvarande tekniken i nyckellös åtkomstkontroll. Den nuvarande tekniken är ett utvärderingspaket från Texas Instrument som används tillsammans med olika typer av antenner. En utförlig undersökning av tekniken avslöjade att den inte implementerar den föreslagna Angle of Arrival-metod för Bluetooth Low Energy men avvikelserna är minimala. Resultat som erhållits från tester med fördröjningslinjer visar tillräckligt noggrannhet för nyckellös åtkomstkontroll. Men ingen av de testade antenntyperna gör det. Arbetet drar slutsatsen att den nuvarande tekniken inte kan användas som nyckellös åtkomstkontroll på grund av starka antennberoende. Framtida arbete föreslås således att fokusera på antennutveckling.
43

Bluetooth Low Energy Communication for Multi-Sensor Applications Design and Analysis

Garretto, Joao 14 December 2022 (has links)
No description available.
44

A Mobile Interface for Real-Time EEG Monitoring

Bhalchandra, Anish 15 June 2017 (has links)
No description available.
45

Analysis of effective energy consumption of Bluetooth Low Energy versus Bluetooth Classic

Tåqvist, Carl, Luks, Jonathan January 2022 (has links)
Wireless technology is used daily across the globe. A very common wireless technology is Bluetooth. The Bluetooth technology exists everywhere, from cars to mobile phones and even kitchen appliances. Recently, Bluetooth Low Energy has added support for another physical layer, LE 2M PHY. This physical layer is supposed to be faster and more energy efficient than its predecessor, LE 1M PHY, with a decrease in range. Because of this new physical layer, Bluetooth Low Energy can now compete with Bluetooth Classic during data transmission, in both speed and energy efficiency. This thesis aims to find the breaking point where Bluetooth Low Energy becomes less energy efficient than Bluetooth Classic, in relation to bit rate speed and total amount of bytes sent. Before experiments were conducted, multiple iterations of an artifact had to be done to end up with an artifact that provides valid and reliable data. The experiments were then conducted by changing the bit rate speed and sending different amounts of bytes. The results from the experiments show that Bluetooth Classic is practically both faster and more energy efficient with its fastest modulation than Bluetooth Low Energy is with LE 2M PHY enabled, even though this should not be the case theoretically. Bluetooth Classic is overall more energy efficient than Bluetooth Low Energy and thus the conclusion of this study is that no breaking points between the two technologies exist.
46

Low-Power Wireless Sensor Node with Edge Computing for Pig Behavior Classifications

Xu, Yuezhong 25 April 2024 (has links)
A wireless sensor node (WSN) system, capable of sensing animal motion and transmitting motion data wirelessly, is an effective and efficient way to monitor pigs' activity. However, the raw sensor data sampling and transmission consumes lots of power such that WSNs' battery have to be frequently charged or replaced. The proposed work solves this issue through WSN edge computing solution, in which a Random Forest Classifier (RFC) is trained and implemented into WSNs. The implementation of RFC on WSNs does not save power, but the RFC predicts animal behavior such that WSNs can adaptively adjust the data sampling frequency to reduce power consumption. In addition, WSNs can transmit less data by sending RFC predictions instead of raw sensor data to save power. The proposed RFC classifies common animal activities: eating, drinking, laying, standing, and walking with a F-1 score of 93%. The WSN power consumption is reduced by 25% with edge computing intelligence, compare to WSN power that samples and transmits raw sensor data periodically at 10 Hz. / Master of Science / A wireless sensor node (WSN) system that detects animal movement and wirelessly transmits this data is a valuable tool for monitoring pigs' activity. However, the process of sampling and transmitting raw sensor data consumes a significant amount of power, leading to frequent recharging or replacement of WSN batteries. To address this issue, our proposed solution integrates edge computing into WSNs, utilizing a Random Forest Classifier (RFC). The RFC is trained and deployed within the WSNs to predict animal behavior, allowing for adaptive adjustment of data sampling frequency to reduce power consumption. Additionally, by transmitting RFC predictions instead of raw sensor data, WSNs can conserve power by transmitting less data. Our RFC can accurately classify common animal activities, such as eating, drinking, laying, standing, and walking, achieving an F-1 score of 93%. With the integration of edge computing intelligence, WSN power consumption is reduced by 25% compared to traditional WSNs that periodically sample and transmit raw sensor data at 10 Hz.
47

Optimisation de la gestion d’énergie dans les systèmes embarqués / Optimization of energy management in embedded systems

Rammouz, Ramzy 05 December 2017 (has links)
Qu’il s’agisse de suivre des patients à domicile, ou de prévenir l’isolement ou la vulnérabilité de personnes âgées, les systèmes de suivi et d'assistance électroniques qui émergent offrent des opportunités sans précédents. L’enjeu est considérable, et on assiste à un développement technologique important qui permet désormais aux particuliers ou aux établissements hospitaliers ou médico-sociaux d’assurer le diagnostic, la prévention, le contrôle, voire le traitement de patients à distance (mesures de paramètres physiologiques, administration de médicaments, détection de chutes, etc.). Ce suivi à distance est en particulier devenu possible et performant avec l’avènement des objets connectés. On peut ainsi envisager d’exploiter un réseau de capteurs embarqué sur un patient pour mesurer à distance et en temps réel la température, le rythme cardiaque ou la tension artérielle d’un patient. Les données sont transmises (et/ou stockées) au praticien pour réaliser le diagnostic et définir les traitements. Pour autant la conception optimale (choix des technologies de transmission, de stockage, etc.) ainsi que la problématique de la gestion d’énergie constituent des verrous à leur adoption. Le travail proposé dans cette thèse consiste donc à développer un outil d’aide à la conception de réseaux de capteurs médicaux communicants embarqués sur la personne. Il s’agit en particulier de fournir une information sur la faisabilité au plus tôt dans le cycle de conception, et garantir l’obtention d’un circuit « correcte par construction ». L’accent est porté sur la maîtrise (voire la réduction) de la consommation d’énergie Dans ce sens, une simulation fiable et précise permet de contrôler, dès le début du flot de conception, la consommation en énergie du réseau. Elle assure par la suite une meilleure gestion de l’énergie disponible et éventuellement une autonomie plus importante. L’outil, centré sur l’optimisation de la consommation d’énergie, est implémenté dans un environnement Matlab. Basé sur une modélisation de la consommation en énergie d’un nœud de capteur, il se veut générique aussi bien que précis. Il assure une implémentation simple de nouveaux composants à partir de fiches techniques. Ces composants sont construits sous la forme de blocs réutilisables permettant ainsi à l’utilisateur de créer sa propre librairie. En plus de l’estimation de la consommation, cet outil met en œuvre des algorithmes d’optimisation pour guider l’utilisateur vers une conception qui respecte les contraintes énergétiques et médicales de l’application (choix de composants, choix de source d’énergie, configuration du réseau, etc.). Une application est proposée d’abord au niveau d’un nœud de capteur de température corporelle communiquant par Bluetooth Low Energy. Ce même nœud est ensuite placé au sein d’un réseau de capteurs pour la surveillance de cinq paramètres physiologiques différents. Une validation expérimentale des résultats de simulation est également réalisée. / Whether it is to monitor patients at home, or to prevent the isolation and vulnerability of the elderly, the emerging electronic monitoring and assistance systems offer new opportunities. The technological development we have witnessed allows individuals, hospitals, or medical aid organizations to provide the diagnosis, prevention, control or even treatment of patients outside of conventional clinical settings (measurements of physiological parameters, drug administration, fall detection, etc.).Recent developments in connected objects made efficient remote patient monitoring possible. In other words, we are able to use a network of wearable or implantable sensors to remotely obtain real time measurements of a patient’s vital signs (temperature, heart rate, blood pressure, etc.). Data is transmitted (and / or stored) to medical personnel who are able to perform diagnosis and define treatments accordingly. An optimal design (transmission protocols, data storage, etc.) and energy management are the bottlenecks involved in the implementation of such systems. This work proposes to develop a tool to help in the design of medical sensor networks. It aims to provide information regarding feasibility during the early stages of the design thus ensuring that a "well-constructed" circuit is obtained. The emphasis is on the control (or even reduction) of energy consumption. In this regard, an efficient energy consumption simulation at the beginning of the design flow would enable the user to decide on system parameters. This will ensure an optimal management of the available energy and eventually a longer network lifetime. The proposed tool is centered on the optimization of the energy consumption using Matlab environment. It is built over a model of the energy consumption of wireless sensor nodes. It is intended to be generic and accurate. In fact, it enables fast creation of new component description based on the datasheets. These components are reusable thus producing a growing database. In addition to energy consumption estimation, the tool uses optimization routines to guide the user through an energy aware design (picking energy sources, components, network configuration, etc.) that complies with medical requirements. An application to a single Bluetooth Low Energy body temperature sensor is first proposed. The same sensor is then included in a physiological sensor network. A physical implementation is used in order to compare the results obtained through simulation with practical measurements.
48

Internet of Things & Kommunikationsprotokoll / Internet of Things & Communication Protocol

Sabel, Ida January 2015 (has links)
Genom att studera olika kommunikationsprotokoll kunna svara på vad det är som gör att ett visst protokoll är bäst anpassat för att användas mellan mobila enheter och IoT-enheter. I arbetet användes en kvalitativ litteraturstudie för att ge en grundlig teoretisk bakgrund samt en experimentell studie där ett par teorier undersökts ifall de stämmer med resultaten ifrån verkligheten. De fem faktorerna kompatibilitet, batteritid, frekvens, räckvidd och tillförlitlighet undersöktes hos kommunikationsprotokollen Bluetooth Low Energy (BLE), Närfältskommunikation (NFC) och Wi-Fi. Dessa tre valdes eftersom de stöds av nyare mobila plattformar idag. Kommunikations-protokollen analyserades sedan gentemot olika användningsområden inom IoT, eftersom påståendet vad som är bäst anpassat beror på vad situationen kräver för egenskaper. En systemutvecklare som ska välja kommunikationsprotokoll till en IoT-tillämpning och läser denna rapport bör själv jämföra de olika protokollen mot varandra inom de fem faktorerna för att kunna avgöra vilket protokoll som passar bäst inom dennes situation. I arbetet utfördes endast experimentella studier på BLE på grund av begränsningar inom utrustningen. Ytterligare experiment inom NFC och Wi-Fi skulle ge ett bredare perspektiv med fler infallsvinklar. / By studying different communication protocols respond to what it is that makes a certain protocol best suited for use between mobile devices and IoT devices. This study used a qualitative literature study to create a proper theoretical background and an experimental study where two theories were investigated in whether they matched wih the results from the reality. The five factors compatibility, battery loss, frequency, range and reliability were investigated in the communication protocols Bluetooth Low Energy (BLE), Near field communication (NFC) and Wi-Fi, these three because they are supported by newer mobile platforms today. The communication protocols were then analysed against various uses in the IoT, since the claim what it is that makes it best suited depends on what the situation requires. A system developer that is about to select the communication protocol to use in an IoT application and reads this study should compare the different protocols to each other within the five factors to determine which protocol is best suited for his situation. This study only performed experimental studies on BLE because of limitations in the equipment. Additional experiments on NFC and Wi-Fi would provide a wider perspective.
49

Message Classification Based Continuous Data Transmission for an E-health Embedded System

Sun, Jiuwu January 2019 (has links)
This thesis aims to develop an e-health embedded system with a real-time operating system (RTOS), which allows users to monitor their body condition, including heart rate and breath, through Bluetooth Low Energy (BLE). Meanwhile, the device is also able to provide guidance for breathing by simulating breathing according to given parameters. In practice, the system samples the heart rate every two milliseconds. To ensure reliability and validity, results are expected to be sent in realtime. However, numerous data cannot be transmitted directly without being processed. Otherwise, the system will crash, and hard faults will occur. A general idea to solve this problem is to classify messages into two categories based on the priority. One is urgent, and the other is unimportant. Two solutions are proposed, one using a unidirectional linked list, and the second using queues. Based on an ARM micro-controller, the e-health embedded system is designed and implemented successfully. The evaluation results show that the solution using a linked list is suitable for the system, while the solution using queues is unable to solve the problem. With the help of the message classification, the urgent messages can be timely transmitted with continuous data. / Avhandlingen syftar till att utveckla ett e-hälso-inbyggt system med ett realtidsoperativsystem (RTOS), som gör det möjligt för användare att övervaka sitt kroppstillstånd, inklusive hjärtfrekvens och andetag, genom Bluetooth Low Energy (BLE). Samtidigt kan enheten också ge vägledning för andning genom att simulera andning enligt givna parametrar. I praktiken samplar systemet hjärtfrekvensen varannan millisekund. För att säkerställa tillförlitlighet och giltighet bör resultaten skickas i realtid. Annars kraschar systemet och allvarliga fel uppstår. En allmän idé för att lösa detta problem är att klassificera meddelanden i två kategorier baserade på prioritering, en är brådskande och den andra är obetydlig. Två lösningar föreslås, en med hjälp av riktad länkad lista och en annan implementerad med hjälp av köer. Resultatmässigt, baserat på en ARM-mikrokontroller, är det inbyggda e-hälsosystemet framgångsrikt designat och konfigurerat. Lösningen med en länkad lista är lämplig för systemet, medan lösningen som implementeras med köer fortfarande inte kan lösa problemet. Med hjälp av meddelandeklassificeringen är de brådskande meddelandena inte ens försenade med kontinuerlig data.
50

Populating a Database to be used with an Indoor Positioning System / Populera en databas som ska användas med ett inomhuspositioneringssystem

Halvarsson, Maria, Qin, Jinglan January 2022 (has links)
Indoor Positioning System (IPS) are becoming more common in many areas such as retail, warehouses, smart facilities, and manufacturing.In recent years, Bluetooth Low Energy (BLE)-based IPS has become increasingly popular due to its low cost and low energy consumption. One of the more recent updates, Bluetooth 5.1, provides the ability to compute the location using Angle of Arrival (AoA) or Angle of Departure (AoD). These new features have allowed for better positioning accuracies, where AoA-based positioning has shown sub-meter accuracy. An application area for BLE-based IPS is retail stores where the technology can benefit both the store and its customers. This thesis investigates how to populate a database to be used with an IPS in a real-life store. The assumption is that customers will have BLE equipped devices and run an application that will send the properly formatted BLE advertisements, such that an BLE IPS can locate the user in the store. Additionally, we assume that the application can use the device's e-compass or other means to determine in which direction the user's device is oriented. Based on the position and orientation of the user, the software is assumed to access a database to know what item(s) are near the customer. However, the question remains of how did this data get into the database? This degree project explores this in detail and assesses the amount of time and effort needed to populate this database and the amount of time and effort needed to keep this database up to date. This project followed an iterative Design Science Research (DSR) methodology where the artifact is the database. A relational database was used as they are widely used and joins can easily be performed and it is easy to modify existing tables. The application was developed in Spring Boot and React. Amazon Web Services (AWS) was used to host and provide the necessary services for the database and application. The result showed that the estimated time needed to populate the database in a supermarket with a sales area of 5300 m2, 36623 products, and 220 containers is 106.64 hours and 107.13 hours in the worst case assuming a walking speed of 1.4 m s-1. Updating a product would take 10.34 s and 10.37 s if the time it takes for a staff member to walk to the place where the product is located is excluded. / Inomhuspositioneringssystem (IPS) har blivit allt vanligare inom många områden. De senaste åren har Bluetooth Low Energy (BLE)-baserad inomhuspositionering blivit mer populärt på grund av egenskaper som låg kostnad och låg energikonsumption. En av de senaste versionerna; Bluetooth 5.1 kan beräkna positionen med hjälp av ankomstvinkeln (eng. Angle of Arrival (AoA)) och utgångsvinkeln (eng. Angle of Departure (AoD)). Angle of Arrival (AoA)-baserad positionering kan uppnå en noggrannhet under 1 m. Ett Bluetooth Low Energy (BLE)-baserat IPS kan tillämpas i butiker där det kan gynna både butikens medarbetare och dess kunder. Detta examensarbete kommer att undersöka hur en databas som ska användas med ett IPS i en butik kan populeras. Antagandet i detta projekt är att kunderna kommer ha BLE utrustade enheter som kör ett program som tillåter att användaren kan lokalisera sig i butiken. Dessutom antar vi att applikationen kan använda enhetens e-kompass eller annan hårdvara för att kunna avgöra i vilken riktning användarens enhet är orienterad. Baserat på användarens position och riktning, antas det att mjukvaran kan komma åt databasen och veta vilka produkter som ligger i närheten av kunden. Dock kvarstår frågan: Hur sparades denna data i databasen? Det här examensarbetet kommer alltså att undersöka hur en databas i en butik kan vara uppbyggd om vi utgår från antagandet att BLE är tillämpat i butiken. Vi kommer även bedöma hur mycket tid som krävs för att populera en databas och hålla denna databas uppdaterad. Ett iterativ arbetsätt tillämpades i examensarbetet. I projektet användes en relationsdatabas eftersom det är enkelt att utföra join-operationer och uppdatera tabbeller i databasen. Applikationen som skapades tillhandahåller funktioner för att spara, uppdatera, radera och söka produkter i databasen. Frontend var kodad i React och backend var kodad i Spring Boot. Amazon Web Services (AWS) molntjänser och deras verktyg användes för att köra applikationen och databasen. Resultatet visade att populera en databas med produkter i en mataffär med en säljyta på 5300 m2, 36623 produkter, och 220 behållare (hyllor, kylskåp, etc.) tog 106.64 timmar i bästa fall och 107.13 timmar i värsta fall om vi antar en gångfart i 1.4 m s-1.

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