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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.
21

An alternative roaming model inLoRaWAN

Lamberg-Liszkay, János, Lisauskas, Tadas January 2018 (has links)
LoRaWAN is an open networking technology designed for IoT devices that al-lows wireless data transmission over longer ranges than some other wireless tech-nologies, like Wi-Fi or Bluetooth, for devices that are constrained in terms of size,price, and available power. The current design of roaming among networks in LoRaWANis heavily inspired by that of mobile networks, as the use of roaming agreementsis mandated. Roaming agreements create unnecessary administrative overhead thathinders deployments. A roaming model that is quicker and simpler to deploy couldsave money for current users, and could even attract new users to the technology.To circumvent the necessity of roaming agreements, a new, scalable and agreement-less roaming model should be proposed. In this thesis project a literature survey isconducted, investigating similar technologies to find hints or inspiration for a newroaming model. It is found that the broker software architecture pattern put in thecontext of roaming in LoRaWAN suits the requirements quite well, so the new roam-ing model has been developed based on that. A software simulation has been imple-mented to gather data regarding the scalability of the model. It has been found thatthe proposed model is both scalable, and agreement-less.
22

Capteur communicant autonome en énergie pour l'loT / Autonomous communicating sensors for IoT

Bouguera, Taoufik 28 March 2019 (has links)
Une grande partie des nouvelles générations d'objets connectés ne pourra se développer que s'il est possible de les rendre entièrement autonomes sur le plan énergétique. Même si l'utilisation de batteries ou de piles résout une partie de ce problème en assurant une autonomie qui peut-être importante avec des coûts relativement faibles, elle introduit non seulement des contraintes de maintenance incompatibles avec certaines applications, mais aussi des problèmes de pollution. La récupération de l'énergie thermique, mécanique, électromagnétique, solaire ou éolienne est une solution très prometteuse. Dans ce cas, la vie de l'objet connecté peut-être prolongée. Cependant, l'énergie récupérée dépend fortement des conditions au voisinage du dispositif et peut donc varier de façon périodique ou aléatoire. Il parait alors important d'adapter le système (mesure et transmission de données) aux contraintes de la récupération d'énergie. L'objectif de la thèse est de proposer une solution de capteur autonome basée sur un système de récupération et de gestion multisources d'énergies (solaire et éolienne) et pouvant-être mis en oeuvre dans différentes classes d'applications IoT. On s'intéresse, dans un premier temps, à la modélisation de la consommation du noeud capteur. Ensuite, on modélise le système de récupération multisources. Puis, on se focalise sur le management de puissance du système autonome. Ce management est basé sur des prédictions de l'énergie disponible et de celle consommée. Enfin, le travail de modélisation et d'optimisation est validé par des expérimentations afin d’avoir un démonstrateur de Capteur Communicant Autonome en Énergie pour les applications IoT. / Researchers aim to develop entirely autonomous sensors. By ensuring an important autonomy, the use of batteries solves part of the energy problem with relatively low costs. However, batteries introduce different problems such as maintenance and environmental pollution. Harvesting thermal, mechanical, electromagnetic, solar or wind energy present in the environment is an attractive solution. Using harvested energy from their surroundings, wireless sensor nodes can significantly increase their typical lifetime. Nevertheless, the harvested energy depends on the surrounding conditions of the device and can vary periodically or randomly. It seems important to adapt the system (measurement and data transmission) to the harvesting energy constraints. The thesis objective is to provide an autonomous sensor solution based on a multisources energy harvesting and management system (solar and wind energies), which can be used in different IoT applications. First, we are interested in modeling and optimizing the sensor node energy consumption. Then, the multiple harvesting system is modeled according to the energy needs of the sensor node. Besides, we focus on the power management of the autonomous system. This management part is based on predictions of both available and consumed energies. Finally, the proposed modeling and optimization studies are validated with experimental works in order to develop an Autonomous Communicating Sensor platform for IoT applications.
23

Estimation of Drone Location Using Received Signal Strength Indicator

Jagini, Varun Kumar 08 1900 (has links)
The main objective of this thesis is to propose a UAV (also called as drones) location estimation system based on LoRaWAN using received signal strength indicator in a GPS denied environment. The drones are finding new applications in areas such as surveillance, search, rescue missions, package delivery, and precision agriculture. Nearly all applications require the localization of UAV during flight. Localization is the method of determining a UAVs physical position using a real or virtual coordinate system. This thesis proposes a LoRaWAN-based UAV location method and presents experimental findings from a prototype. The thesis mainly consists of two different sections: one is the distance estimation and the other is the location estimation. First, the distance is estimated based on the mean RSSI values which are recorded at the ground stations using the path loss model. Later using the slant distance estimation technique, the path loss model parameters L and C are estimated whose values are unknown at the beginning. These values completely depend on the environment. Finally, the trilateration system architecture is employed to find the 3-D location of the UAV.
24

Realize Smart City Applications with LoRaWAN Network

Wang, Bin January 2019 (has links)
Internet of Things is an important part of realizing smart cities, this article introduces a proposal to build an Internet of Things system with LoRaWAN to achieve diverse smart city applications. There are three problems proposed and resolved in this research, how to maximize wireless devices’ lifetime with LoRa protocol characters, how to choose the gateways’ location for improving the efficiency and reduce costs, and about a good way to set up network servers to balance performance and consumption to implement in smart city applications. The IoT platform is built completely and running three applications on it in this research, Smart Parking, Smart Building Monitoring and Smart Sewage Monitoring. The methods of build platform and set applications are also explained in this article.
25

An evaluation of coverage models for LoRa

Paulsson, Felix, Bitar, Issa January 2021 (has links)
LoRaWAN is a wireless network technology based on the LoRa modulation technology. When planning such a network, it is important to estimate the network’s coverage, which can be done by calculating path loss. To do this, one can utilize empirical models of radio wave propagation. Previous research has investigated the accuracy of such empirical models for LoRa inside cities. However, as the accuracy of these models is heavily dependent on the exact characteristics of the environment, it is of interest to validate these results. In addition, the effect of base station elevation on the models’ accuracy has yet to be researched. Following the problems stated above, the purpose of this study is to investigate the accuracy of empirical models of radio wave propagation for LoRa in an urban environment. More specifically, we investigate the accuracy of the models and the effect of base station elevation on the models’ accuracy. The latter is the main contribution of this study. To perform these investigations, a quantitative experiment was conducted in the city of Jönköping, Sweden. In the experiment a base station was positioned at elevations of 30, 23, and 15m. The path loss was measured from 20 locations around the base station for each level of elevation. The measured path loss was then compared to predictions from three popular empirical models: the Okumura-Hata model, the COST 231-Walfisch-Ikegami model, and the 3GPP UMa NLOS model. Our analysis showed a clear underestimation of the path loss for all models. We conclude that for an environment and setup similar to ours, models underestimate the path loss by approximately 20dB. They can be improved by adding a constant correction value, resulting in a mean absolute error of at least 3,7-5,6dB. We also conclude that the effect of base station elevation varies greatly between different models. The 3GPP model underestimated the path loss equally for all elevations and could therefore easily be improved by a constant correction value. This resulted in a mean absolute error of approximately 4dB for all elevations.
26

Bezpečná autentizace a klíčový management v Internetu věcí / Secure Authentication and Key Management in the Internet of Things

Škunda, Patrik January 2018 (has links)
This thesis deals with issues of secure authentication and key management in the Internet of Things. It describes basic protocols used in IoT, cryptographic primitives, communication technologies in IoT and end elements. It also includes a measuring the performance of cryptographic primitives on Raspberry Pi and selecting the appropriate LPWAN simulation technology. The conclusion of the work is devoted to the simulation of a LoRaWAN network
27

Obecná bezpečnost Internetu věcí / General Security of the Internet of Things

Páleník, Luděk January 2018 (has links)
The thesis "General Security of the Internet of Things" deals with the analysis of networks with low power consumption in the theoretical part -- especially LoRaWAN networks. Further, the thesis deals with the general security of the Internet of things and the security risks of LoRaWAN networks. The practical part is focused on building the LoRaWAN gateway, which is realized with the Raspberry Pi platform with the iC880A-SPI extension module. The gateway is put into operation with full settings, assignment to the network server. Sensors configuration, creation an application, and assign it to the application server. In the practical part, a replay attack on LoRaWAN technology, which demonstrates the vulnerability of this technology, is realized.
28

Lokalizace v rámci technologie LoRaWAN / Localization in LoRaWAN technology

Pospíšil, Jan January 2019 (has links)
The diploma thesis in theoretical part focuses on LPWAN in general, meaning the low power wireless device falling into IoT category with a focus on LoRaWAN. The second half of the theoretical part focuses on describing localization techniques and principles in general and selection of one suitable technique for implementation in LoRaWAN. The practical part focuses on the proper HW customizations to enable the localization in this network. There are also described all the steps needed to build the whole working LoRaWAN network. The TDoA localization algorithm is described, the functionality is verified by simulation and also by testing under real conditions. In the end, the results are explained, the shortcomings of the technology are described and finally a suggestion for improvement is provided.
29

Nízkoenergetický GPS lokátor s použitím LoRa sítě / Low Energy GPS Tracker Using LoRa Network

Múčka, Milan January 2020 (has links)
This thesis deals with determine location using very low power consumption device. The main target was to design and construct device using right platform and sensors for localization, sending data using IoT LoRa network and than processing data on server's side. To solve the problem, it was used community network TheThingsNetwork. In thesis I created power efficient device, which can find current location using GPS system and deliver it to user using LoRaWAN network.
30

Implementace a vyhodnocení komunikační technologie LoRaWAN v simulačním prostředí NS-3 / Implementation of the LoRaWAN Communication Technology Using the Network Simulator 3

Mašek, Petr January 2021 (has links)
The diploma thesis focuses on the description of LPWAN (Low Power Wide Area Network) technologies for use in IoT (Internet of Things) communication scenarios. The theoretical part compares communication technologies operating in the license-exempt frequency band, i.e. Sigfox and LoRaWAN (Long Range Wide Area Network). Furthermore, technologies using the licensed frequency spectrum are discussed, specifically, attention is focused on NB-IoT (Narrow Band IoT). Emphasis is placed on LoRaWAN technology and the properties of the unlicensed frequency band below the 1 GHz, which is utilized by this technology. The practical part of the thesis consists of the evaluation of simulation scenarios using an integrated module in the simulation environment NS-3 (Network Simulator 3). Attention is focused mainly on the analysis of data transmission success using selected communication parameters of LoRaWAN technology. The obtained simulation outputs with a focus on mMTC (massive Machine-Type Communication) communication scenarios confirm the relationship between the number of end devices and gateways, communication distance and transmission reliability, or the limit value for the duty cycle.

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