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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.
81

Komunikační technologi ZigBee v automatizaci budov / ZigBee in Building Automation

Liška, Radovan January 2011 (has links)
Improvement of wireless technologies is a natural consequence of the progress in the field of science and technology. Usage of wireless networks based on the ZigBee technology, which are capable of indepent operation in present form, providing detailed information about physical environment and process management, brings many advantages. On the other hand, there is a serious issue about commissioning. This Master's Thesis deals with introduction of ZigBee technology and its usage, describes issue about device commissioning and types of commissioning. The main part of the Thesis is my own proposal for solving this problem, proposing algorithm using the Bitcloud stack for Coordinator, End Device and Router and its demonstration at the application. Along with analysing the application there are described possible solutions for creating a new network, adding a new node into the existing network and changing a node. The result is a graphical application and firmware for each device. The result of succesfully associated devices in network is supported by the measurement.
82

Zigbee zařízení pro monitorování spotřeby elektrické energie / Zigbee node for monitoring of electric energy consumption

Štefany, Martin January 2012 (has links)
Master's thesis designs a device for monitoring of electric energy consumption with ability to send measured data wirelessly using ZigBee technology. Theoretical part describes basic principles for measuring electric power and energy and also a possibility of digital measurement. Thesis provides short overview of already existing solutions for electric consumption measurement available on the market as well. Further the ZigBee standard is described together with one of its software implementations named BitCloud from Atmel Corporation. Design of the device deals with the selection of suitable integrated circuit for the consumption measurement and optimal voltage and current sensors. Then also its connection with the wireless module named ZigBee using SPI bus, power supply for the entire device and also the design of PCB. There is also a firmware implementation for the designed device based on BitCloud. Description of the firmware together with calibration process implemented is also part of the thesis. Finally, basic device testing and packet analysis of communication between designed device and ZigBee network coordinator is described.
83

Výzkum systému GPS pro lokalizaci bezdrátových senzorových uzlů / Research into GPS system used for Wireless Sensor Node Localization

Juračka, Jan January 2013 (has links)
Theme of the thesis is research and possibility of using GPS system from localization in wireless sensor network. Paper deals with the accuracy and energy consumption of GPS localization. Thesis also solve using of localization in local anchor system. Theoretical part describes IEEE 802.15.4 standard, capability of used nodes and describe ways how to use RSSI value to resolve location
84

Lokalizace uzlů v seznorové síti ZigBee / Node Location in the ZigBee Network

Capalini, Richard January 2010 (has links)
The master thesis is concerned with problem of localization of nodes in wireless sensor network WSN implemented by ZigBee technology. The thesis provide description of ZigBee architecture involving signal description. The method of evaluating coordinates basically do not depend on used measuring methods. The method  of fingerprinting is included in separated category based on only statistical processing of RSSI data. Determination of coordinates of mobile node always needs finding out range, signal time of arrival (ToA) or angle of arrival (AoA) in respect to anchors node given dimension magnitude. The author found out three possible solutions for range measuring and one solution for angle of arrival measuring useable in context of ZigBee wireless sensor network. Finally the author discuss possibilities and constraints of ZigBee network with used measuring type.
85

Jednotka pro řízení motorů dávkovacích čerpadel / Pump Control System

Streit, Jakub January 2016 (has links)
The goal of this thesis is design of universal system for motor control. This device must be able to control at least 4 motors, stepper motors or DC motors. Wired, or wireless communication, using IEEE 802.15.4, is mandatory. The System is based on modular concept. The Basic modules are Control module, Communication module, Connection module and Power module. The system was tested in the control of fertilizer dosing pumps in the greenhouse
86

2.4-GHz Wireless Network Based Multi-Tag Access System

Ye, Qianyun January 2015 (has links)
Machine-to-Machine technology has been intensively researched recently which is believed to take the role of leading ICT industry development. Wireless Sensor Networks provide solution to integrate numerous numbers of machines who require features include low power, low cost, and flexible, which can be fulfilled by applying Zigbee technique. This thesis devotes an effort into Wireless Sensor Network development that a Multi- Tag System operating on 2.4-GHz wireless network is developed. A theoretical study about ZigBee protocol and its bottom layers IEEE 802.15.4 standard is provided to lay a foundation of the design work. The thesis also includes a practical usage of low cost TI CC2530 Systom-on-Chip, together with the illustration of software development inside the chip. The design work provides GUI Platform for users to register themselves into the network and central monitoring platform to track all users within the area. Both GUI platforms are developed based on VB IDE. The Multi-Tag Access System is suitable for attendee control functionality in big-scale conference, events, and lecture, which is also a prototype expecting more functionality to be added in the future.
87

Integration of UAVS with Real Time Operating Systems and Establishing a Secure Data Transmission

Ravi, Niranjan 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In today’s world, the applications of Unmanned Aerial Vehicle (UAV) systems are leaping by extending their scope from military applications on to commercial and medical sectors as well. Owing to this commercialization, the need to append external hardware with UAV systems becomes inevitable. This external hardware could aid in enabling wireless data transfer between the UAV system and remote Wireless Sensor Networks (WSN) using low powered architecture like Thread, BLE (Bluetooth Low Energy). The data is being transmitted from the flight controller to the ground control station using a MAVlink (Micro Air Vehicle Link) protocol. But this radio transmission method is not secure, which may lead to data leakage problems. The ideal aim of this research is to address the issues of integrating different hardware with the flight controller of the UAV system using a light-weight protocol called UAVCAN (Unmanned Aerial Vehicle Controller Area Network). This would result in reduced wiring and would harness the problem of integrating multiple systems to UAV. At the same time, data security is addressed by deploying an encryption chip into the UAV system to encrypt the data transfer using ECC (Elliptic curve cryptography) and transmitting it to cloud platforms instead of radio transmission.
88

Síťová architektura a propojování vestavěných systémů / Network Architecture and Interconnection of Embedded Systems

Trchalík, Roman January 2013 (has links)
The thesis focuses on the architecture of embedded systems. It summarizes the current state of accepted standards from IEEE 1451 family, which deals with creating an environment for the sensors and their involvement in various networks. These standards describe the open, network-independent communication architecture for a sensor-based system. One of the main outcomes of this work is the architectures presented as case studies, which can be used as design patters for embedded applications. They are demonstrated on ZigBee technology suitable mainly for small devices with very low power consumption. Based on these studies the new design of universal gateway was proposed. Its major advantage is that it allows interconnection of the endpoints based on different sensor network technologies. Additionally, the thesis deals with modifying the routing protocol of ZigBee network in order to reduce power consumption required to transmit one data packet.
89

Operating systems for resource constraint Internet of Things devices: An evaluation

Elvstam, Andreas, Nordahl, Daniel January 2016 (has links)
Internet of Things (IoT) är ett område under omfattande utveckling, både vad det gäller hårdvara och mjukvara. När det gäller hårdvaruplattformar för IoT enheter finns det platt-formar som är kraftfulla nog att exekvera ett reguljärt OS som t.ex. Linux. Andra hårdvaru-plattformar är inte tillräckligt kraftfulla för att exekvera reguljära OS och för dessa plattformar finns ett behov av resurseffektiva små IoT OS. Dessa resurssnåla OS behöver kunna hantera många av de funktioner som reguljära OS erbjuder, men på ett betydligt mer effektivt sätt.Det har under de senaste åren släppts en uppsjö av olika IoT OS för resurssnåla enheter och därför är syftet med denna rapport en utvärdering av IoT OS för strömsnåla resurssvaga IoT enheter. Utvärdering genomförs på IoT OS:en Contiki, mbed, RIOT och Zephyr. Målet med utvärderingen är att fastställa viktiga egenskaper för ett IoT OS för strömsnåla resurssvaga IoT enheter, och att belysa svårigheter och erfarenheter relaterade till konstruktionsprocessen av en prototyp för IoT enheter. Utvärderingen genomfördes genom att samla in fyra olika typer av data relaterade till IoT OS:en, och sedan utvärdera denna data med hjälp av en kriteriebaserad utvärderingsmetod.Utvärderingen resulterade i en lista av sex viktiga egenskaper för små resurs snåla IoT operativsystem. Dess resultat belyser även svårigheter och erfarenheter som framkommit under byggprocessen av prototyperna baserade på IoT OS:en.Slutsatsen av denna rapport bidrar med erfarenheter från byggning av prototyper IoT OS för resurssnåla enheter, samt ett utvärderingsresultat för IoT OS:en med hänsyn till de sex viktiga IoT OS egenskaperna. / The Internet of Things (IoT) is a large and rapidly expanding area with regards to both hardware platforms and software. When it comes to hardware platforms for the IoT some are more powerful and able to run a traditional OS like Linux, while other platforms are too constraint to do so. To ease the development within the IoT area an appropriate IoT OS is needed for these constrained hardware platforms, which can handle most of the functionality a traditional OS offer.Therefore, we evaluate IoT OSs targeted for low performance battery powered devices. In this thesis Contiki, mbed, RIOT and Zephyr are evaluated. The aim of this evaluation is to determine important IoT OS characteristics for resource constrained devices, and to highlight difficulties and experiences related to the building process of prototypes for such IoT devices.The evaluation of the IoT OSs were conducted on four types of data with regards to several measurable OS characteristics according to a criteria based evaluation method.The evaluation resulted in a list of six IoT OS characteristics important for wireless, resource constrained and battery powered devices. Furthermore the evaluation highlights potential setbacks during the building process of a prototype system for such devices and it also explains what experiences that can be gained.The conclusion of this thesis contributes with experience related to IoT OS prototype construction and also an evaluation result with respect to the six IoT OS characteristics for constraint battery driven devices.
90

Hybrid FPGA and GPP Implementation of IEEE 802.15.4 Physical Layer

Jeong, Jeong-O 28 August 2012 (has links)
In this thesis, two different cases of hybrid IEEE 802.15.4 PHY (Physical Layer) implementation are explored. The first case is an FPGA implementation of IEEE 802.15.4 PHY on the Xilinx Spartan-3A DSP FPGA of USRP N210. All of the signal processing tasks are performed on the FPGA, while less complex MAC (Media Access Control) layer tasks are performed in GNU Radio on the host. The second case is an implementation of a multi-channel IEEE 802.15.4 receiver. A four-channel channelizer is implemented on the external Virtex 5 FPGA, while the IEEE 802.15.4 receiver is implemented in GNU Radio on the host. The first case demonstrates how spare resources in USRP's FPGA can be used to implement signal processing task while still interfacing with GNU Radio. The second case builds a platform on which a combination of GNU Radio and an external FPGA can be used for signal processing and USRP as an RF source. This thesis lays out the groundwork for more complex wireless protocols to be implemented on any combination of USRP's FPGA, an external FPGA, and GNU Radio. / Master of Science

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