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

Investigating the practical performance of the LoRaWAN technology

Skog Andersen, Jonas, Eriksson, Joakim January 2017 (has links)
New innovations, technologies, ideas and businesses are driving the realisation of the Internet of Things (IoT) vision. As with many other fields in technology comes competing protocols and standards, ranging from modulation schema used for transmitting data to security standards used to ensure safe operation and the privacy needs for all involved entities. This thesis looks into one of the competing modulation schema and network protocols for IoT applications: the LoRaWAN protocol. The main contribution of this thesis is a datadriven empirical study that helps verify theoretically obtained results from other authors. Our results also suggest that as long as other signals on the same frequency band uses different modulation techniques (or just other parameters for the same modulation technique), then only the signal to noise ratio is affected without introducing collisions. This affects the scalability and overall practical distance covered by a LoRaWAN. Our general conclusion is that the LoRaWAN as a technology/protocol has its disadvantages, mainly how heavily different traffic profiles may affect the scalability of it and a general lack of hard quality of service guarantees.
2

Comparison Study and Product Development using Wireless Narrowband Low-power Wide-area Network Technologies

Ortis Pasamontes, Enrique January 2017 (has links)
Nowadays it is more clear that the Internet of things (IoT) is not a transient trend but a completely new industry. The internet of things has the capability to enhance current industries (Industry 4.0), as well as to help protecting the environment and people. The latter is the case with the system developed and described in this thesis. The possibilities that IoT brings are due to the interconnection of heterogeneous embedded devices to the internet. This thesis focus on LPWANs (Low Power Wide Area Networks), which is a new set of technologies specifically design for the needs of IoT devices.Due to the recent deploy of NB-IoT (Narrow Band IoT) networks it has become more difficult to know what LPWAN is best for a certain application. Thus, the first half of this thesis involves the comparative study of NB-IoT and LoRaWAN LPWANs. This comparison required an in depth study of each technology, specially on the physical and datalink layers. The comparison briefly displays the main characteristics of each technology and explain the main conclusions in a concise manner. The second part of the thesis describes the development of a GNSS tracker. This tracker will be used on train wagons carrying goods that are dangerous for people and the environment. This thesis report describes the different steps taken, from the requirement specification to the partial development of the software.
3

[en] MACHINE LEARNING-BASED MAC PROTOCOLS FOR LORA IOT NETWORKS / [pt] PROTOCOLOS MAC BASEADOS EM APRENDIZADO DE MÁQUINA PARA REDES DE INTERNET DAS COISAS DO TIPO LORA

DAYRENE FROMETA FONSECA 24 June 2020 (has links)
[pt] Com o rápido crescimento da Internet das Coisas (IoT), surgiram novas tecnologias de comunicação sem fio para atender aos requisitos de longo alcance, baixo custo e baixo consumo de energia exigidos pelos aplicativos de IoT. Nesse contexto, surgiram as redes de longa distância de baixa potência (LPWANs), as quais oferecem diferentes soluções que atendem aos requisitos dos aplicativos de IoT mencionados anteriormente. Entre as soluções LPWAN existentes, o LoRaWAN tem-se destacado por receber atenção significativa da indústria e da academia nos últimos anos. Embora o LoRaWAN ofereça uma combinação atraente de transmissões de dados de longo alcance e baixo consumo de energia, ele ainda enfrenta vários desafios em termos de confiabilidade e escalabilidade. No entanto, devido a sua natureza de código aberto e à flexibilidade do esquema de modulação no qual ele se baseia (Long Range (LoRa) permite o ajuste de fatores de espalhamento e a potência de transmissão), o LoRaWAN também oferece importantes possibilidades de melhorias. Esta dissertação aproveita a adequação dos algoritmos de Aprendizagem por Reforço (RL) para resolver tarefas de tomada de decisão e os utiliza para ajustar dinamicamente os parâmetros de transmissão dos dispositivos finais LoRaWAN. O sistema proposto, chamado RL-LoRa, mostra melhorias significativas em termos de confiabilidade e escalabilidade quando comparado ao LoRaWAN. Especificamente, diminui a taxa de erro de pacote (PER) média do LoRaWAN em 15 porcento, o que pode aumentar ainda mais a escalabilidade da rede. / [en] With the massive growth of the Internet of Things (IoT), novel wireless communication technologies have emerged to address the long-range, lowcost, and low-power consumption requirements of the IoT applications. In this context, the Low Power Wide Area Networks (LPWANs) have appeared, offering different solutions that meet the IoT applications requirements mentioned before. Among the existing LPWAN solutions, LoRaWAN has stood out for receiving significant attention from both industry and academia in recent years. Although LoRaWAN offers a compelling combination of long-range and low-power consumption data transmissions, it still faces several challenges in terms of reliability and scalability. However, due to its open-source nature and the flexibility of the modulation scheme it is based on (Long Range (LoRa) modulation allows the adjustment of spreading factors and transmit power), LoRaWAN also offers important possibilities for improvements. This thesis takes advantage of the appropriateness of the Reinforcement Learning (RL) algorithms for solving decision-making tasks, and use them to dynamically adjust the transmission parameters of LoRaWAN end devices. The proposed system, called RL-LoRa, shows significant improvements in terms of reliability and scalability when compared with LoRaWAN. Specifically, it decreases the average Packet Error Ratio (PER) of LoRaWAN by 15 percent, which can further increase the network scalability.
4

Diseño de un sistema de mensajería instantánea para redes comunitarias

Nakamura Pinto, Miguel Kiyoshy 31 October 2022 (has links)
[ES] Cerca de 3.000 millones de personas en todo el mundo no pueden aprovechar ni siquiera los servicios de conectividad más básicos, ya que la mayoría de ellas viven en zonas rurales o países en vías de desarrollo. Incluso los servicios de mensajería más simples serian de gran ayuda, por ejemplo, para los agricultores que desean conocer el precio de las mercancías que les interesa vender o comprar antes de decidir si se emprende un viaje posiblemente largo, caro y agotador. La tecnología LoRa permite realizar enlaces de larga distancia con un consumo reducido de energía a bajo coste, siendo su principal limitación el escaso ancho de banda que ofrece. Con LoRa, los lugares remotos, como las zonas rurales, pueden beneficiarse de servicios basados en la conectividad que, de otro modo, serían imposibles. Nuestra propuesta entra en la categoría de redes comunitarias, en las que los usuarios construyen su propia red cuando no hay infraestructura comercial disponible. Además de la simple aplicación de mensajería, LoRa puede utilizarse para distribuir información de sensores a las comunidades o para proporcionar alertas de desastres o datos meteorológicos. Presentamos un protocolo flexible basado en la tecnología LoRa que permite la transferencia de "contenido" denominado LoRaCTP, el cual proporciona los mecanismos necesarios para que LoRa sea fiable, introduciendo una configuración de conexión ligera. Hemos diseñado este protocolo también como soporte de comunicación para las soluciones IoT basadas en edge computing, dada su estabilidad, el bajo consumo de energía y la posibilidad de cubrir largas distancias. Integramos una arquitectura que permite la recolección de datos de fuentes externas genéricas. Especialmente las fuentes de audio, apuntando a dos servicios básicos: un sistema de mensajería de voz que permite a los usuarios que no saben leer o escribir, realizar notas de voz, y un servicio de compresión de audio para extraer las principales características de la entrada de audio y utilizarla para desarrollar análisis de audio inteligente basado en Machine Learning. Combinamos IoT y Edge computing en un enfoque de innovación frugal, para proponer una solución "ingeniosa", en términos de utilización mínima de recursos y sostenibilidad, para construir un soporte básico para un sistema IoT en áreas rurales. Incluimos un proxy MQTT para integrar dispositivos de bajo coste y bajo consumo en un sistema de mensajería basado en LoRa. A través de una interfaz REST, mostramos cómo se puede usar nuestra plataforma para distribuir información de sensores de las comunidades rurales. Además, MQTT permite que estos datos se proporcionen a "lagos de datos" externos para que puedan usarse para tareas tales como informes, visualización, análisis avanzado y aprendizaje automático. Describimos una arquitectura genérica de edge/fog, utilizando microservicios, un sistema basado en MQTT que puede recopilar datos de ingreso, manejar su persistencia y coordinar la integración de datos con la nube utilizando un servicio específico llamado agregador. Las estaciones edge tienen un canal dedicado con el agregador que se basa en LoRa para permitir transmisiones de largo alcance con bajo consumo de energía. / [CA] Prop de 3.000 milions de persones a tot el món no poden aprofitar ni tan sols els serveis de connectivitat més bàsics, ja que la majoria d'elles viuen en zones rurals o països en vies de desenvolupament. Fins i tot els serveis de missatgeria més simples serien de gran ajuda, per exemple, per als agricultors que desitgen conèixer el preu de les mercaderies que els interessa vendre o comprar abans de decidir si s'emprèn un viatge possiblement llarg, car i esgotador. La tecnologia LoRa permet realitzar enllaços de llarga distància amb un consum reduït d'energia a baix cost, sent la seua principal limitació l'escassa amplada de banda que ofereix. Amb LoRa, els llocs remots, com les zones rurals, poden beneficiar-se de serveis basats en la connectivitat que, d'una altra manera, serien impossibles. La nostra proposta entra en la categoria de xarxes comunitàries, en les quals els usuaris construeixen la seua pròpia xarxa quan no hi ha infraestructura comercial disponible. A més de la simple aplicació de missatgeria, LoRa pot utilitzarse per a distribuir informació de sensors a les comunitats o per a proporcionar alertes de desastres o dades meteorològiques. Presentem un protocol flexible basat en la tecnologia LoRa que permet la transferència de "contingut" denominat LoRaCTP, el qual proporciona els mecanismes necessaris perquè LoRa siga fiable, introduint una configuració de connexió lleugera. Hem dissenyat aquest protocol també com a suport de comunicació per a les solucions IoT basades en edge computing, donada la seua estabilitat, el baix consum d'energia i la possibilitat de cobrir llargues distàncies. Integrem una arquitectura que permet la recol·lecció de dades de fonts externes genèriques. Especialment, les fonts d'àudio, apuntant a dos serveis bàsics: un sistema de missatgeria de veu que permet als usuaris que no saben llegir o escriure realitzar notes de veu, i un servei de compressió d'àudio per a extraure les principals característiques de l'entrada d'àudio i utilitzar-la per a desenvolupar anàlisi d'àudio intel·ligent basat en Machine Learning. Combinem IoT i Edge computing en un enfocament d'innovació frugal, per a proposar una solució "enginyosa", en termes d'utilització mínima de recursos i sostenibilitat, per a construir un suport bàsic per a un sistema IoT en àrees rurals. Incloem un proxy MQTT per a integrar dispositius de baix cost i baix consum en un sistema de missatgeria basat en LoRa. A través d'una interfície REST, vam mostrar com es pot usar la nostra plataforma per a distribuir informació de sensors de les comunitats rurals. A més, MQTT permet que aquestes dades es proporcionen a "llacs de dades" externes perquè puguen usar-se per a tasques com ara informes, visualització, anàlisi avançada i aprenentatge automàtic. Descrivim una arquitectura genèrica de edge/fog, utilitzant microserveis, un sistema basat en MQTT que pot recopilar dades d'ingrés, manejar la seua persistència i coordinar la integració de dades amb el núvol utilitzant un servei específic anomenat agregador. Les estacions edge tenen un canal dedicat amb el agregador que es basa en LoRa per a permetre transmissions de llarg abast amb baix consum d'energia. / [EN] Nearly 3 billion people around the world are unable to take advantage of even the most basic connectivity services, as most of them live in rural areas or developing countries. Even the simplest messaging services would be of great help, for example, to farmers who want to know the price of goods they are interested in selling or buying before deciding whether to embark on a possibly long, expensive and exhausting journey. LoRa technology enables long-distance links with reduced power consumption at low cost, its main limitation being the low bandwidth it offers. With LoRa, remote locations, such as rural areas, can benefit from connectivity-based services that would otherwise be impossible. Our proposal falls into the category of community networks, where users build their own network when commercial infrastructure is not available. In addition to a simple messaging application, LoRa can be used to distribute sensor information to communities or to provide disaster alerts or weather data. We present a flexible protocol based on LoRa technology that enables the transfer of "content" called LoRaCTP, which provides the necessary mechanisms for LoRa to be reliable, introducing a lightweight connection setup. We have designed this protocol also as a communication support for IoT solutions based on edge computing, given its stability, low power consumption and the possibility of covering long distances. Likewise, we integrated an architecture that allows data collection from generic external sources. Especially audio sources, targeting two basic services: a voice messaging system that allows users who cannot read or write to make voice notes, and an audio compression service to extract the main features of the audio input and use it to develop intelligent audio analytics based on Machine Learning. We combine IoT and Edge computing in a frugal innovation approach, to propose an "ingenious" solution, in terms of minimum resource utilization and sustainability, to build a basic support for an IoT system in rural areas. We include an MQTT proxy to integrate low-cost and low-power devices into a LoRa-based messaging system. Through a REST interface, we show how our platform can be used to distribute sensor information from rural communities. In addition, MQTT allows this data to be provided to external "data lakes" so that it can be used for tasks such as reporting, visualization, advanced analytics, and machine learning. We describe a generic edge/fog architecture, using microservices, an MQTT-based system that can collect ingress data, manage its persistence, and coordinate data integration with the cloud using a specific service called an aggregator. The edge stations have a dedicated channel with the aggregator that is based on LoRa to enable long-range transmissions with low power consumption. / Agradezco al Gobierno de los Estados Unidos Mexicanos a través del Consejo Nacional de Ciencia y Tecnología (CONACYT) y al Gobierno de Chiapas mediante el Consejo de Ciencia y Tecnología del Estado de Chiapas (COCYTECH) por brindarme la oportunidad de mejoramiento profesional y académico por medio del programa de becas “CONACYT - Gobierno del Estado de Chiapas” en la convocatoria del 2017. / Nakamura Pinto, MK. (2022). Diseño de un sistema de mensajería instantánea para redes comunitarias [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/188948

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