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La technologie RFID (Radio Frequency Identification) prend une place de plus en plus importante dans la société d'aujourd'hui notamment dans des domaines aussi variés que la santé, la sécurité, la logistique... Le développement de cette technologie met en évidence de nouvelles contraintes comme la réduction des zones de lecture et la géo-localisation pour le stockage et le suivi de marchandises. Dans ce contexte, la thèse s'est focalisée sur le développement d'antennes pour lecteur RFID dans le cadre du projet SPINNAKER piloté par TAGSYS RFID et soutenu par OSEO. L'objectif de cette étude est de concevoir des antennes compactes et directives à polarisation circulaire en bande UHF et SHF. L'antenne hélice présente toutes ces caractéristiques à l'exception de la hauteur, très importante dès que l'on souhaite obtenir des performances élevées surtout en gain. Dans ce manuscrit, trois solutions sont proposées pour réduire la hauteur de l'antenne hélice tout en répondant aux cahiers des charges. La première solution consiste à utiliser un réflecteur de forme cylindrique ou conique qui permet de réduire la hauteur d'une antenne hélice classique d'un facteur quatre pour atteindre 0,9λ. La réduction de la hauteur se traduit par une augmentation de la surface autour de l'antenne avec une dimension latérale de 2,3λ. La seconde solution consiste à utiliser l'antenne hélice avec une cavité Fabry-pérot. La hauteur du système antennaire obtenue est de 0,5λ avec un diamètre de 2λ. La dernière solution développée dans la thèse introduit une surface CMA à la solution précédente qui permet de réduire la hauteur à 0,25λ. Toutes les solutions proposées ont été validées expérimentalement. / Over the past 20 years, the RFID (Radio Frequency Identification) technology is having a huge expansion. Nowadays, it is frequently used in different areas as the health, the security and the logistic. A lot of researches are ongoing on this topic, especially in order to reduce the reading zone of the readers and to locate the tags. This thesis focuses on the development of new antennas for Readers RFID devices and is part of the SPINNAKER project supported by OSEO. The antennas requirements are circular polarization, high directivity and gain with low profile. The helix antennas meet all these requirements except the axial length. In this manuscript, we propose three solutions to reduce the helix antenna axial length. The first one uses a cylindrical or conical optimal reflector to reduce the length by four. This reduction affects directly the surface witch increases up to 2.3λ. The second solution uses the helix antenna as a circular polarization feed for a Fabry-Perot (FP) cavity. The final antenna presents a cavity height of 0.5λ and a 2λ diameter. The last solution conserves the FP cavity in which we include an Artificial Magnetic Conductor (AMC) to reduce the cavity height to 0.25λ. All these solutions are validated by measurements.

Radio Frequency Identification (RFID) technology is a ethod of identifying unique items using radio waves that communicate between RFID tags and readers without line-of-sight readability. RFID technology provides great potential in many industries and a wide spectrum of possible uses. Areas of application include person identification, logistics, pharmaceutical, access control, security guard monitoring and asset management. One of the areas where RFID is being used and where it promises excellent results is the retail industry. While RFID systems have the potential to revolutionise the way products and goods are tracked and traced in the retail supply chain, barriers to its widespread adoption exist: for example; technical constraints, return on investment constraints, a lack of awareness and education and as well as privacy and security issues. The research aims to identify the barriers to the adoption of RFID and to investigate the perceptions of RFID held by members of the retail sector in South Africa (SA). Current research and available literature are used to identify RFID adoption barriers and a conceptual framework on this subject is proposed, which is then verified by SA retailers’ perceptions, established by means of a survey. Initial barriers to widespread adoption include a shortage in skills, a lack of standards, high costs associated with RFID devices, the difficulty of integrating with current legacy systems, and a lack of familiarity with the system. Finally, an enhanced framework is proposed, describing RFID adoption barriers within the South African retail sector. In summary, the framework is an outline of the barriers impacting RFID adoption in the SA retail sector that need to be considered and addressed. The framework identifies six categories of RFID adoption barriers, with each category containing two or more barriers relating to that particular category. These categories are Technological, Cost and return on investment, Privacy and security, Implementation, Organisational factors and People.

The diploma thesis deals with the rationalization of the flow of transport units among the company Continental Teves CZ, s.r.o. and suppliers. The objective of the thesis is to map the flow of transport units, to suggest possible solutions and to pass judgment on a possible implementation of automatic identification that can facilitate monitoring of such marked transport units. The theoretical part of the thesis describes specifics of automotive industry and of supply chains that operate there.

To overcome the hurdles associated with space management and security controls in a housing system, research was projected to study and analyze the necessary factors of accomplishment. Over time, different processes were observed and reviewed to make this a possible deal. Various residents were interviewed on the daily constraints in parking and managing their vehicles within their housing premises. The reported daunting concern was majorly the gate access and personal hunts for the space to keep the individual resident’s cars. Every resident would always have to stop and hoot at the housing gate for the assigned personnel to check and open the gate. While this would waste every resident’s time, the visitors even face more delay often time. Hitherto, car access and parking constraint become a thing of worry that no one would want to engage the housing service anymore. The interest has got dwindled. And to re-awaken the high patronage of the housing system, a gap must be bridged with an immediate solution to space management with a gating system. These were subsequently given a classical thought, while a prototype solution was demonstrated and reviewed with the various residents of some selected housing. This received a high welcoming embracement and was beckoned to be made real by the logical heuristic. At this point, nothing was further considered than using the Internet of things (IoT) technology to implement Vehicular Access Management for the control and integration of intended space provisioning in any housings. Consequently, the number plate of every vehicle becomes the automatic access tag and would be used for security control within the housing location. Vehicles’ numbers would be captured and used to manage the residents passing through the automated gating system. With it, records would be made for all permitted residents and the visitors that own a car. Thus, a proper arrangement would be allotted accordingly, as provisioned by the gating system administrator. However, to allegories the above-proffered solution, this project work is divided into six sections. The introductory section introduces the project rationale, lists the objectives, explores related works, and introduces how IoT and vehicular systems can be merged. The second section delves into these vehicular systems. It introduces the Automatic License Plate Recognition System (ALRP) and the Raspberry Pi and highlights the merits of the Integrated Vehicular Access Security System. Open-CV and machine learning are also introduced. Section three covers the solution design, while section four is the implementation phase. Section five covers the testing and implementation of the solution. The final section summarizes the project. The project successfully models an automated solution for the security of tenants and vehicle users against unauthorized access to residential estates and buildings.

Orientador: Alexandre César Rodrigues da Silva / Resumo: Transmissão de dados sem fio tem se tornado cada vez mais presente no dia a dia, devido a comodidade da não utilização de cabos, bem como pela maior mobilidade propiciada. Este trabalho aborda duas tecnologias de comunicação sem fio atuais: Identificação por Radiofrequência (RFID) e Bluetooth, destacando suas principais características e apresenta o protótipo de um circuito que efetua a leitura de tags fixadas em objetos, por meio de um leitor RFID e, posteriormente, transmite a identificação dessas a um smartphone, por meio da tecnologia Bluetooth. Com o propósito de ilustrar aplicações do protótipo construído, foram desenvolvidos dois softwares para smartphones Android: um de controle de medicamento de idosos e outro para auxiliar deficientes visuais nas aulas práticas laboratoriais. Durante o desenvolvimento do trabalho, testes foram realizados para se verificar o alcance de leitura do leitor RFID utilizado. Também foram realizados testes com a tecnologia Bluetooth, verificando-se a distância máxima de conexão e transmissão/recepção de dados entre o protótipo desenvolvido e um smartphone. / Abstract: Wireless data transmission has become increasingly present in everyday life, because the convenience of not using cables, as well as the greater mobility afforded. This paper addresses two current wireless communication technologies: Radio Frequency Identification (RFID) and Bluetooth, highlighting its main characteristics and presents the prototype of a circuit that performs the reading tags attached to objects by means of an RFID reader and later transmits the identification to such a smartphone, using Bluetooth technology. In order to illustrate prototype built applications, they developed two software for Android smartphones: one for the elderly medicine control and another to assist the visually impaired in the laboratory classes. During the development work, tests were conducted to verify the read range of the RFID reader used. Also with Bluetooth technology tests were performed, checking the maximum distance connection and transmission/reception of data between the developed prototype and a smartphone. / Mestre

dreimal im Jahr erscheinende Zeitschrift über aktuelle Themen der TU Chemnitz

dreimal im Jahr erscheinende Zeitschrift über aktuelle Themen der TU Chemnitz

The construction industry is vital in meeting humanity's infrastructure and essential building needs. However, its current practices contribute significantly to environmental challenges such as global warming, deforestation, and biodiversity loss. The current study points out the need for a more sustainable approach in the construction sector. The reason this study focuses on RFID-tags is both because of the academic gap regarding implementation of new standardizations and the project Lumi that this study has as its case study of the thesis.    The goal of this thesis is to analyze the Swedish construction industry’s attitude toward the implementation of RFID-tags as a standardization and fill the academic gap that has been identified in the literature review. The goal is to determine the attitude of each stakeholder type within the industry through the lens of socio-technical transition theory, to determine specific barriers and drivers for the concept. Furthermore, the aim is to determine if RFID-tags can be implemented to promote circularity and enhance sustainable development.   The research methods incorporate a literature review and a case study with semi-structured interviews conducted with eight participants. The sample consisted of actors within the construction industry, such as customers, distribution companies, entrepreneurs, manufacturers, service companies, and workers.  The thesis identified the conservative nature of the industry as an obstacle, along with the fear of failure within the construction industry. The attitude towards the standardization of RFID-tags is positive, where beneficial factors were identified, such as saving time, reducing environmental impact, and improving the structure for recycling.

Surface acoustic wave (SAW) sensors offer a wireless, passive sensor solution for use in numerous environments where wired sensing can be expensive and infeasible. Single carrier frequency SAW sensor embodiments such as delay lines, and resonators have been used in single sensor environments where sensor identification is not a necessity. The orthogonal frequency coded (OFC) SAW sensor tag embodiment developed at UCF uses a spread spectrum approach that allows interrogation in a multi-sensor environment and provides simultaneous sensing and sensor identi- fication. The SAW device is encoded via proper design of multiple Bragg reflectors at differing frequencies. To enable accurate device design, a model to predict reflectivity over a wide range of electrode metallization ratios and metal thicknesses has been developed and implemented in a coupling of modes (COM) model. The high coupling coefficient, reflectivity and temperature coefficient of delay (TCD) of YZ LiNbO3 makes it an ideal substrate material for a temperature sensor, and the reflectivity model has been developed and verified for this substrate. A new concept of pseudo-orthogonal frequency coded (POFC) SAW sensor tags has been investigated, and with proper design, the POFC SAW reduces device insertion loss and fractional bandwidth compared to OFC. OFC and POFC sensor devices have been fabricated at 250 MHz and 915 MHz using fundamental operation, and 500 MHz and 1.6 GHz using second harmonic operation. Measured device results are shown and compared with the COM simulations using the iii enhanced reflectivity model. Additionally, the first OFC devices at 1.05 GHz were fabricated on 128o YX LiNbO3 to explore feasibility of the material for future use in OFC sensor applications. Devices at 915 MHz have been fabricated on YZ LiNbO3 and integrated with an antenna, and have then been used in a transceiver system built by Mnemonics, Inc. to wirelessly sense temperature. The first experimental wireless POFC SAW sensor device results and predictions will be presented.