Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2017-01-30T12:31:14Z No. of bitstreams: 1 PEDRO RINALDO CHAVES.pdf: 3607910 bytes, checksum: e6c9f208a2f52773a6226da6c4212ab9 (MD5) / Made available in DSpace on 2017-01-30T12:31:14Z (GMT). No. of bitstreams: 1 PEDRO RINALDO CHAVES.pdf: 3607910 bytes, checksum: e6c9f208a2f52773a6226da6c4212ab9 (MD5) Previous issue date: 2016-12-05 / The demand for wireless sensor networks (WSN) applied to industrial process monitoring and control should increase as the forth industrial revolution (Industry 4.0) gathers pace, since one if its main caracteristics is about flexible plant set-up. Flexibility and low cost make the WSN the perfect choice for the modern 21st century manufacturing plants. Small and medium enterprises (SMEs) have an important role in the development of the Latin America economies. This paper first describes the tests done in two industrial environments, analyses the results and examines the behaviour of a low cost, centralized WSN in industrial environments to ascertain the impact of the processes and environment (topology, distances, barriers, machines and people) in the radio signal and discuss the reliability and applicability of WSNs in process monitoring and control. The results obtained with the tests indicated a relationship between the received signal strength indicator (RSSI), the packet error rate (PER), the environment and the processes generating subsidies to the network management system. Subsequently, a new management strategy is presented, it includes two RSSI tracking indexes that guarantee an early warning in case the radio signal deteriorates. With the knowledge gathered, a set of best practices is presented; it covers the planning, installation and commissioning of centralized low cost WSNs for SMEs. / A demanda por redes de sensores sem fio (RSSF) aplicadas ? monitora??o e controle de processos em ambientes industriais de todos os tamanhos tende a aumentar ? medida que a quarta revolu??o industrial (Industry 4.0) avan?a, sendo que uma das suas caracter?sticas ? a flexibiliza??o da disposi??o dos equipamentos (plant set-up). A flexibilidade e baixo custo das RSSF as tornam a escolha perfeita para estas novas instala??es manufatureiras do s?culo 21. As pequenas e m?dias manufaturas (SMEs) tem um papel importante no desenvolvimento das economias da Am?rica Latina. Neste trabalho, primeiro descrevem-se os testes e analisa-se o comportamento de uma rede centralizada de sensores sem fio (RCSSF) de baixo custo, em dois ambientes industriais de m?dio porte de forma a se determinar como o ambiente (topologia, dist?ncias, barreiras, maquin?rio e pessoas) e os processos impactam o sinal de r?dio. Pondera-se tamb?m sobre a confiabilidade e aplicabilidade das RCSSF na monitora??o e controle de processos industriais que, por vezes, podem ser cr?ticos. Os resultados mostram uma rela??o entre par?metros como o indicador da intensidade do sinal recebido (RSSI), a taxa de erros do pacote (PER), o ambiente e os processos fornecendo assim subs?dios para a ger?ncia da rede. Posteriormente, apresenta-se uma nova estrat?gia de ger?ncia que consiste em dois ?ndices que rastreiam e monitoram o n?vel do RSSI garantindo um alerta precoce caso o sinal de r?dio apresente deteriora??o. Com os conhecimentos adquiridos, conclui-se o trabalho com a apresenta??o de um conjunto de melhores pr?ticas para auxiliar no planejamento, implanta??o e comissionamento de RCSSF de baixo custo voltadas ?s SMEs.

Στην παρούσα εργασία έγινε μια πρώτη προσπάθεια ενασχόλησης με τα Ασύρματα Δίκτυα Αισθητήρων, πιο γνωστά στον επιστημονικό κόσμο ως Wireless Sensor Networks ή WSNs. Μελετήσαμε τα βασικά χαρακτηριστικά των δικτύων αυτών, όπως οι τοπολογίες τους και η αρχιτεκτονική τους. Επίσης, μελετήσαμε την αρχιτεκτονική των ασύρματων κόμβων που απαρτίζουν το δίκτυο, που είναι γνωστά σαν motes. Τα motes έχουν την ικανότητα τοπικής επεξεργασίας των δεδομένων που συλλέγουν και την ασύρματη μετάδοσή τους σε έναν κεντρικό σταθμό για περαιτέρω επεξεργασία. Τη λειτουργία αυτή διεκπαιρεώνει μια μονάδα μικροεπεξεργαστή με τη χρήση ενός ολοκληρωμένου chip για την ασύρματη μετάδοση. Για τη συλλογή των μετρήσεων μπορούν να φιλοξενήσουν διάφορες πλατφόρμες ψηφιακών αισθητήρων. Στην παρούσα εργασία έγινε χρήση της υπολογιστικής μονάδας micaz και της πλατφόρμας αισθητήρων MTS400/420. Οι πλατφόρμες αυτές φιλοξενούν αισθητήρες υγρασίας/θερμοκρασίας, βαρομετρικής πίεσης/θερμοκρασίας, φωτεινότητας, μέτρησης δονήσεων και ειδικά η 420 πλατφόρμα έχει υποδοχή και για μονάδα GPS. Σκοπός μας ήταν η ανάπτυξη ενός γραφικού περιβάλλοντος μέσω του οποίου θα απεικονίζαμε τις μετρήσεις που έστελναν στον υπολογιστή τα motes. Η ανάπτυξη του γραφικού περιβάλλοντος έγινε στο Matlab. Για το σκοπό αυτό, ήταν απαραίτητη η σύνδεση ενός mote στον υπολογιστή που θα λειτουργούσε σαν ενδιάμεσος αποδέκτης των δεδομένων και θα τα προωθούσε στον υπολογιστή μέσω της σειριακής θύρας. Για την προβολή και αποθήκευση των δεδομένων στον υπολογιστή, έγινε χρήση του interface Χlisten. / At this thesis there was a first attempt of occupation with Wireless Sensor Networks, most kown to the scientific world as WSNs. We studied the basic characteristics of these networks such as topologies and architecture. We also studied the architecture of the wireless nodes which form the network, also known as motes.The motes have the ability of local data computation and the wireless transmition of them to a base station, where they can further processed. This ability is performed by a microprocessor unit with the use of a single integrated chip responsible for the radio transmition. The data collection can be performed by many digital sensor platforms. At this paper, it has been used the micaz computional unit and the MTS400/420 sensor platform of Crossbow company. These platforms are integrated with sensors that measure relative humidity/temperature, barometric pressure/temperature, illumination, acceleration on axis x and y and especially the 420 platform can integrate a GPS module. Our goal is the development of a Graphical User Interface (GUI) through which we can plot the data that the sensors would send. The development of GUI made with Matlab. For this purpose, it was necessary the connection of a mote to the computer, that would behave like an intermediate receiver and would forward the data packets to the computer through the serial port. The MIB520 board was used for this purpose. For the data projection and saving to the computer, the xlisten interface was used.

Τις τελευταίες δεκαετίες ο όρος τεχνολογία έχει συνδεθεί στενά με την επιστήμη των υπολογιστών και την επεξεργασία της πληροφορίας. Από την στιγμή που η πληροφορία έχει πάρει ψηφιακή μορφή γίνεται ευκολότερη η επεξεργασία της, γεγονός που δημιουργεί ολοένα και υψηλότερες απαιτήσεις στην διαδικασία μεταφοράς της. Αυτό έχει σαν αποτέλεσμα την υλοποίηση δικτύων υπολογιστών μέσω -συνδυασμού ή όχι - ενσύρματων, ασύρματων ή οπτικών καναλιών μετάδοσης. Η εξέλιξη των τελευταίων χρόνων ειδικότερα στον χώρο των ασύρματων τηλεπικοινωνιών και ηλεκτρονικών, έχει ανοίξει τον δρόμο για την δημιουργία ασύρματων δικτύων αισθητήρων – WSN (Wireless Sensor Networks) χαμηλού κόστους. Ένα τέτοιο δίκτυο αποτελείται από ένα σύνολο κόμβων (nodes) πυκνά τοποθετημένων μεταξύ τους. Κάθε ένας από αυτούς αποτελείται από μια διάταξη αισθητήρων και έναν μικροελεγκτή. Με αυτόν τον τρόπο έχει την δυνατότητα να υλοποιεί απλούς υπολογισμούς και να στέλνει τα απαραίτητα μηνύματα στο δίκτυο. Η μεταφορά των μηνυμάτων ακολουθεί τυχαία ή προκαθορισμένη διαδρομή (routing) με απόσταση έναν κόμβο τη φορά (one hop). Μέσα από μια σειρά τέτοιων μεταφορών (multi-hop), τα δεδομένα που συλλέγονται από τους κόμβους φθάνουν στον κεντρικό υπολογιστή για την τελική επεξεργασία και απεικόνιση. Τα ασύρματα δίκτυα αισθητήρων χρησιμοποιούνται σε εφαρμογές που έχουν σχέση με την παρατήρηση και καταγραφή φυσικών φαινόμενων, ή ανίχνευση συμβάντων (event – driven). / The last decades the term “technology” has been closely related to the computers science and the process of information. By the time information has had a digital form its process has become easier, something that creates more demands at the process of its transfer. This results to the computer networks – combining or not – wired, wireless or fiber optics. Last year’s development especially in the field of wireless telecommunications has helped the creation of WSN (Wireless Sensor Networks) of low cost. Such a network is consisted of a set of nodes closely located. Each one is consisted of an arrangement of sensors and a microcontroller, having the potential to carry out simple calculations and sending the required data to the network. This transmission follows a random or a predetermined routing with one hop distance. The data collected from the nodes reach the central computer for the final process and depiction through a series of multi-hop. The Wireless Sensor Networks are utilized in applications related to the observation of natural phenomena or tracing events (event-driven).

Yes / Sensing coverage and network connectivity are two of the most fundamental issues to ensure that there are effective environmental sensing and robust data communication in a WSN application. Random positioning of nodes in a WSN may result in random connectivity, which can cause a large variety of key parameters within the WSN. For example, data latency and battery lifetime can lead to the isolation of nodes, which causes a disconnection between nodes within the network. These problems can be avoided by using mobile data sinks, which travel between nodes that have connection problems. This research aims to design, test and optimise a data collection system that addresses the isolated node problem, as well as to improve the connectivity between sensor nodes and base station, and to reduce the energy consumption simultaneously. In addition, this system will help to solve several problems such as the imbalance of delay and hotspot problems. The effort in this paper is focussed on the feasibility of using the proposed methodology in different applications. More ongoing experimental work will aim to provide a detailed study for advanced applications e.g. transport systems for civil purposes. / European Union’s Horizon 2020 research and innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424.

Wireless sensor networks form an emerging class of computing devices capable of observing the world with an unprecedented resolution, and promise to provide a revolutionary instrument for environmental monitoring. Such a network is composed of a collection of battery-operated wireless sensors, or sensor nodes, each of which is equipped with sensing, processing and wireless communication capabilities. Thanks to advances in microelectronics and wireless technologies, wireless sensors are small in size, and can be deployed at low cost over different kinds of environments in order to monitor both over space and time the variations of physical quantities such as temperature, humidity, light, or sound. In environmental monitoring studies, many applications are expected to run unattended for months or years. Sensor nodes are however constrained by limited resources, particularly in terms of energy. Since communication is one order of magnitude more energy-consuming than processing, the design of data collection schemes that limit the amount of transmitted data is therefore recognized as a central issue for wireless sensor networks. An efficient way to address this challenge is to approximate, by means of mathematical models, the evolution of the measurements taken by sensors over space and/or time. Indeed, whenever a mathematical model may be used in place of the true measurements, significant gains in communications may be obtained by only transmitting the parameters of the model instead of the set of real measurements. Since in most cases there is little or no a priori information about the variations taken by sensor measurements, the models must be identified in an automated manner. This calls for the use of machine learning techniques, which allow to model the variations of future measurements on the basis of past measurements. This thesis brings two main contributions to the use of learning techniques in a sensor network. First, we propose an approach which combines time series prediction and model selection for reducing the amount of communication. The rationale of this approach, called adaptive model selection, is to let the sensors determine in an automated manner a prediction model that does not only fits their measurements, but that also reduces the amount of transmitted data. The second main contribution is the design of a distributed approach for modeling sensed data, based on the principal component analysis (PCA). The proposed method allows to transform along a routing tree the measurements taken in such a way that (i) most of the variability in the measurements is retained, and (ii) the network load sustained by sensor nodes is reduced and more evenly distributed, which in turn extends the overall network lifetime. The framework can be seen as a truly distributed approach for the principal component analysis, and finds applications not only for approximated data collection tasks, but also for event detection or recognition tasks. / Les réseaux de capteurs sans fil forment une nouvelle famille de systèmes informatiques permettant d'observer le monde avec une résolution sans précédent. En particulier, ces systèmes promettent de révolutionner le domaine de l'étude environnementale. Un tel réseau est composé d'un ensemble de capteurs sans fil, ou unités sensorielles, capables de collecter, traiter, et transmettre de l'information. Grâce aux avancées dans les domaines de la microélectronique et des technologies sans fil, ces systèmes sont à la fois peu volumineux et peu coûteux. Ceci permet leurs deploiements dans différents types d'environnements, afin d'observer l'évolution dans le temps et l'espace de quantités physiques telles que la température, l'humidité, la lumière ou le son. Dans le domaine de l'étude environnementale, les systèmes de prise de mesures doivent souvent fonctionner de manière autonome pendant plusieurs mois ou plusieurs années. Les capteurs sans fil ont cependant des ressources limitées, particulièrement en terme d'énergie. Les communications radios étant d'un ordre de grandeur plus coûteuses en énergie que l'utilisation du processeur, la conception de méthodes de collecte de données limitant la transmission de données est devenue l'un des principaux défis soulevés par cette technologie. Ce défi peut être abordé de manière efficace par l'utilisation de modèles mathématiques modélisant l'évolution spatiotemporelle des mesures prises par les capteurs. En effet, si un tel modèle peut être utilisé à la place des mesures, d'importants gains en communications peuvent être obtenus en utilisant les paramètres du modèle comme substitut des mesures. Cependant, dans la majorité des cas, peu ou aucune information sur la nature des mesures prises par les capteurs ne sont disponibles, et donc aucun modèle ne peut être a priori défini. Dans ces cas, les techniques issues du domaine de l'apprentissage machine sont particulièrement appropriées. Ces techniques ont pour but de créer ces modèles de façon autonome, en anticipant les mesures à venir sur la base des mesures passées. Dans cette thèse, deux contributions sont principalement apportées permettant l'applica-tion de techniques d'apprentissage machine dans le domaine des réseaux de capteurs sans fil. Premièrement, nous proposons une approche qui combine la prédiction de série temporelle avec la sélection de modèles afin de réduire la communication. La logique de cette approche, appelée sélection de modèle adaptive, est de permettre aux unités sensorielles de determiner de manière autonome un modèle de prédiction qui anticipe correctement leurs mesures, tout en réduisant l'utilisation de leur radio. Deuxièmement, nous avons conçu une méthode permettant de modéliser de façon distribuée les mesures collectées, qui se base sur l'analyse en composantes principales (ACP). La méthode permet de transformer les mesures le long d'un arbre de routage, de façon à ce que (i) la majeure partie des variations dans les mesures des capteurs soient conservées, et (ii) la charge réseau soit réduite et mieux distribuée, ce qui permet d'augmenter également la durée de vie du réseau. L'approche proposée permet de véritablement distribuer l'ACP, et peut être utilisée pour des applications impliquant la collecte de données, mais également pour la détection ou la classification d'événements.

The battery driven nature of wireless sensor networks, combined with the need of extended lifetime mandates that energy efficiency is a metric with high priority. In the current thesis we explore and compare the energy dissipation of di fferent processor architectures and how it is associated with performance and area requirements. The processor architectures are di erentiated based on the datapath length (16-bit, 32-bit, 64-bit and 128-bit) and the corresponding size of the data memories. Our study focuses on AES algorithm, and the indicated processor architectures support AES forward encryption, CCM (32/64/128), CBC (32/64/128) and CTR common modes of operation. In each processor architecture the instruction set is extended to increase the efficiency of the system. / -

No description available.

Wireless sensor networks (WSN) play an important role in today’s monitoring and controlsystems like environmental monitoring, military surveillance, industrial sensing and control, smarthome systems and tracking systems. As the application of WSN grows by leaps and bounds, there is anincreasing demand in placing a larger number of sensors and controllers to meet the requirements. Theincreased number of sensors necessitates flexibility in the functioning of nodes. Nodes in wirelesssensor networks should be capable of being dynamically reconfigured to perform various tasks is theneed of the hour.In order to achieve flexibility in node functionality, it is common to adopt reconfigurablearchitecture for WSN nodes. FPGA-based architectures are popular reconfigurable architectures bywhich WSN nodes can be programmed to take up different roles across time. Area and power are themajor overheads in FPGA based architectures, where interconnect consumes more power and area thanlogic cells. The contemporary WSN standard requires longer battery life and micro size nodes for easyplacement and maintenance-free operation for years together.Three solutions have been studied and evaluated to approach this problem: 1) Homogenousembedded FPGA platform, 2) Power gated reconfigurable finite state machines and 3) Pass transistorlogic (PTL) based reconfigurable finite state machines. Embedded FPGA is a CMOS 65nm customdeveloped small homogenous FPGA which holds the functionality of the WSN nodes and it will bedynamically reconfigured from time to time to change the functionality of the node. In Power gatedreconfigurable FSM architecture, the functionality of the node is expressed in the form of finite statemachines, which will be implemented in a LUT based power gated design. In PTL based reconfigurablefinite state machine architecture, the finite state machines are completely realized using PTL basedcustom designed sets of library components. Low power configuration memory is used to dynamicallyreconfigure the design with various FSMs at different times.

The IEEE 802.15.4 standard is a low-power, low-rate MAC/PHY standard that meets most of the stringent requirements of single-hop wireless sensor networks. Sensor networks with nodal populations comprised of thousands of devices have been envisioned in conjunction with environmental, vehicular, and military applications, to mention a few. However, such large sensor network deployments necessitate multi-hop support as well as low power consumption. In light of the standard's extremely limited joint support of the two aforementioned attributes, this thesis presents two essential contributions. First, a framework is proposed to implement a new IEEE 802.15.4 operating mode, namely the synchronized peer-to-peer mode. This mode is designed to enable the standard's low-power features in peer-to-peer multi-hop-ready topologies. The second contribution is a distributed Guaranteed Time Slot (dGTS ) management scheme designed to function in the newly devised network mode. This protocol provides reliable contention-free access in peer-to-peer topologies in a completely distributed manner. Assuming optimal routing, our simulation experiments reveal perfect delivery ratios as long as the traffic load does not reach or surpass its saturation threshold. dGTS sustains at least twice the delivery ratio of contention access under sub-optimal dynamic routing. Moreover, the dGTS scheme exhibits minimum power consumption by eliminating the retransmissions attributed to contention, which in turn reduces the number of transmissions to a minimum. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2007-10-25 14:55:36.811

This diploma thesis is dedicated to one of the problems in wireless sensor networks – over the air upgrade (OTAU) of nodes. The requirements for upgrade and possible ways how to transfer new firmware image to nodes are stated in the first chapter. The second chapter is focused on solving the problem of firmware dissemination to whole network based on analysis of known protocols. The practical part of this thesis deals with OTAU design and implementation in Lightweight Mesh software stack from Atmel. Proposed system was tested on deRFnode platform with plugged in deRFmega128 module. The upgrade process of designed system is evaluated on test network in last part. Practical test results are compared with OTAU solution for BitCloud.