Purpose: This thesis aims to describe how to design and implement an IoT-Based digital twin framework for environmental monitoring in the indoor environment.  To fulfill the purpose of the study, the following research question is answered. How to create a digital twin solution utilizing AWS to establish interaction and convergence between the physical environment in a classroom and the virtual environment?  Method: As a research method, the research has conducted design science research (DSR). DSR is a new method, and it is an effective tool for enhancing engineering education research methods.  Results: The study describes in detail the steps required to create the framework. The framework enabled interaction and convergence between the physical and virtual environments in a particular location.  Implications: The research contributes to broadening the knowledge on using the Internet of things (IoT), digital twin (DT), and Amazon web services (AWS). The study provides future research with reference data and a framework to build upon.  Research Limitation: Due to time constraints, the study's scope and limitations are limited to the technologies that the participating company, Knowit, provides. Knowit AB is a Swedish IT consulting company that supports companies and organizations with services in digital transformation and system development. The study aims to create an AWS-based IoT framework, not improve the digital twin concept. The framework was implemented at Jönköping University. This work is also limited to temperature and light intensity as environmental parameters.

Integration of optical wireless communications (OWC) within switched-mode power supplies (SMPS) / Although visible light communication(VLC) systems can provide high density links for use with IoT devices, an energy efficient, high rate method of designing a VLC transmitter is still unclear. Present designs for transmitters such as the bias-T, designs with switch manipulation, and interleaved converters are not commercially viable due to costly and complex designs that sacrifice energy efficiency for data rate. A design allowing for efficient, high rate communications, while maintaining a low cost would allow for widespread adoption of this technology. In this thesis, a novel approach of integrating power converters and VLC systems is explored by replacing commutating diodes with LEDs. By leveraging switched-mode power supply(SMPS) structures, the power dissipated within the converter may be harnessed and used for communications. The result is a simple and energy efficient solution capable of high rate links. Simulation and experimental results demonstrate buck and boost SMPS topologies that simultaneously increase energy efficiency and provide communications at SMPS switching rate without increasing component count. / Thesis / Master of Applied Science (MASc)

La compagnie Sigfox est reconnue comme un acteur prometteur pour des transmissions de longue-distance et faible consommation, dans le contexte de l'IoT. La modulation à bande ultra étroite (Ultra Narrow Band (UNB)), la technologie de communication choisie par Sigfox, permet de transmettre des informations dans des bandes de signal très étroites (typiquement 100 Hz). A cause de l'imprécision fréquentielle causée par les oscillateurs générateurs de fréquence, il n'est pas réaliste de transmettre des signaux UNB dans des canaux parfaitement orthogonaux. L'accès naturel au canal radio pour le système de UNB est de type ALOHA, avec un aspect aléatoire à la fois en en temps et en fréquence. Cet accès aléatoire peut introduire des collisions qui dégradent la performance du réseau. Le but de cette thèse est de caractériser la capacité des réseaux basés sur UNB, ainsi que d’améliorer la performance en considérant l'aspect aléatoire en temps et en fréquence. La première contribution de cette thèse, est une évaluation de la capacité en théorie et en simulation pour une seule station de base (BS), sous des conditions de canal idéaliste ou réaliste. En conditions idéalistes, nous avons exprimé la capacité pour le cas de l'ALOHA généralisé, et l'avons étendu aux cas de réplications. Pour les conditions réalistes, nous avons pris en compte l'interférence spectrale d'UNB et le path loss (sans et avec Rayleigh fading) afin de caractériser la performance des réseaux UNB, avec l'outil géométrie stochastique. La deuxième contribution est d'appliquer l’annulation successive d'interférence (SIC), qui nous permet d'atténuer les interférences, dans des réseaux de UNB. Nous avons fourni une analyse théorique de la performance des réseaux en considérant le SIC et l'interférence spectrale de UNB, pour le cas de mono-BS. La troisième contribution est l'amélioration de la performance des réseaux UNB, en exploitant la diversité de multi-BS. Nous avons fait une analyse théorique de performance en considérant multi-BS et selection combining (SC). En particulier, nous avons considéré que l’interférence vue par chaque BS est corrélée. Nous avons ainsi démontré mathématiquement que cette corrélation ne peut pas être supprimée dans des systèmes UNB. Ensuite, nous avons appliqué les technologies de la combinaison des signaux plus complexes comme MRC (max ratio combining) et EGC (equal gain combining), ainsi que le SIC à travers multi-BS. Nous avons évalué l'amélioration de performance que chaque technologie apporte, et les avons comparées. Nous avons souligné l'efficacité de ces technologies qui nous permettent d’obtenir des gains importants comparés au cas mono-BS (e.x. 125 fois plus de réduction d'erreur avec SIC globale). La dernière contribution est une validation expérimentale du modèle d'interférence spectrale de UNB, ainsi que la capacité des réseaux UNB, sur un testbed de radio FIT/Cortexlab. / Sigfox rises as a promising candidate dedicated for long-distance and low-power transmissions in the IoT backgrounds. Ultra Narrow Band (UNB), being the communication technology chosen by Sigfox, allows to transmit information through signals whose bandwidth is very limited, typically 100 Hz. Due to the imprecision restraint on electronic devices, it is impossible to transmit UNB signals in orthogonal channels. The natural radio access for this kind of system is thus random ALOHA, in both time and frequency domain. This random access can induce collisions which degrades the networks performance. The aim of this thesis is to characterize the capacity of UNB based networks, as well as to enhance its performance, by considering the randomness in time and frequency. The first contribution of the thesis, is the theoretical and numerical capacity evaluation under idealized and realistic channel conditions, for mono base station (BS) case. Under idealized conditions, we have quantified this capacity for generalized ALOHA case and extended for replications. We highlight the time-frequency duality in UNB systems, and that there exists an optimum replication number for a given network parameter set. Under realistic conditions, we have taken into account the specific spectral interference of UNB systems and propagation path loss (without and with Rayleigh fading) to characterize the performance, with the aid of stochastic geometry. The second contribution is the enhancement of UNB network performance in single BS case. We propose to use successive interference cancellation (SIC) in UNB networks, which allows to mitigate the interference. We have provided a theoretical analysis by considering both SIC and the spectral interference, for mono-BS case. We bring to light the efficiency of SIC in enhancing UNB system performance. The third contribution is the improvement of UNB systems, by exploiting the multiple BS diversity. An analytical performance evaluation considering the simplest selection combining is conducted. In particular, we consider the interference viewed by all the BSs are correlated. Then we apply more complex signal combining technologies such as MRC (max ratio combining) and EGC (equal gain combining), and even interference cancellation across multi-BS in UNB networks. We evaluate the performance improvement that each technology can bring, and compare them with each other. We highlight the efficiency of these multi-BS technologies which allow us to achieve significant performance enhancement compared to mono-BS (e.x. 125 times better performance with global SIC). Last but not least, we experimentally verify the the spectral interference model and network capacity on a cognitive radio testbed.

Submitted by Fernanda Ciolfi (fernanda.ciolfi@puc-campinas.edu.br) on 2016-08-11T19:28:00Z No. of bitstreams: 1 Vitor Queiroz Pereira.pdf: 3873709 bytes, checksum: 35cd48e3c95401712d40707f6b9e1af3 (MD5) / Made available in DSpace on 2016-08-11T19:28:00Z (GMT). No. of bitstreams: 1 Vitor Queiroz Pereira.pdf: 3873709 bytes, checksum: 35cd48e3c95401712d40707f6b9e1af3 (MD5) Previous issue date: 2016-06-23 / The characteristics of the Sensors Wireless Networks (WSNs) make this technology a solution for a variety of purposes, including when it comes to Internet of Things (IoT). Formed by sensor nodes, this type of network is responsible for monitoring and acting on various aspects of the environment to measure temperature or trigger an exhaust fan. However, wireless communication is vulnerable environment changes in which it operates, which could compromise the effectiveness of communication. Thus, this work presents a proposal for a methodology to determine optimal routes based on an estimate of the PER by the RSSI and a protocol for the collection of network RSSIs. The estimated PER was developed by experimental tests with FSK modulation. The collection protocol was implemented in a real network and RSSIs used to determine the best routes. The methodology for allocation of routes was developed with the classification premise of us according to the criticality of your application into two groups, high and low criticality. / As caracter?sticas das Redes de Sensores Sem Fio (RSSF) fazem desta tecnologia uma solu??o para diversas finalidades, inclusive quando se trata de Internet das Coisas (IoT). Formada por n?s sensores, este tipo de rede ? respons?vel por monitorar e atuar em diferentes aspectos do ambiente, como medir a temperatura ou acionar um exaustor. Entretanto, a comunica??o sem fio ? vulner?vel as mudan?as do ambiente em que est? inserida, podendo comprometer a efic?cia da comunica??o. Neste sentido, este trabalho apresenta uma proposta uma de metodologia para determina??o de melhores rotas baseada em uma estimativa da PER pela RSSI e um protocolo para a coleta das RSSIs da rede. A estimativa da PER foi desenvolvida por meio de testes experimentais com a modula??o FSK. O protocolo de coleta foi implementado em uma rede real e as RSSIs utilizadas na determina??o de melhores rotas. A metodologia para atribui??o de rotas foi desenvolvida baseada na classifica??o dos n?s em fun??o de sua criticidade.

The door manufacturing industry still heavily relies on manual technology for its production and quality assurance systems, which poses certain challenges. However, in recent years, the industry has witnessed a growing demand for personalized products, leading to a need for more adaptable production methods and shorter product life cycles. Unfortunately, this reliance on manual technologies has resulted in increased errors and inaccuracies. Moreover, manual technology requires significant time and effort investment, which reduces production efficiency and product quality. To address these issues, the purpose of this thesis is to address the issue of inefficiency at a door manufacturing company by examining its existing production systems and quality assurance system. The thesis aims to provide recommendations for improvement by exploring the integration of automated tracing and tracking technology. Furthermore, it would result in recommendations for feasible methods that may be used in Swedish production systems, as well as further study fields.