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ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The ability to accurately measure the temperature of different materials has always been a challenge for the Instrumentation Engineer. The use the classic contact type temperature detector such as thermocouples or RTD’s (Resistance Temperature Detectors) has not always shown to be the best approach to obtain the expected measurement. When not used carefully in closed environments, thermocouples and RTD’s could report the environmental temperature rather than the temperature from the product under examination. They are also temperature limited and when needed for applications above those limits, very expensive and low reliable materials are necessary to do the job. The use of non-contact thermometers has become the preferred choice for such applications. They have also come as a solution for the difficulties involved in the temperature measurements of moving targets. The industry has used portable and spot type infrared thermometers for some time, but the demand for better and more precise measurements has brought an incredible number of new products to the market. By means of advanced electronics and new software developments these products are used to cope with the difficulties of acquiring challenging measurements. Some of the same demands have made necessary the use of non-contact temperature measurement devices on aircraft instrumentation applications. The use of these capabilities has allowed the data acquisition community to get valuable data that was very difficult if not impossible to obtain before. In spite of all these facts, this promising emerging technology demands very careful attention before it is put to good use. The many products and solutions available do not accurately address every problem and the selection of the wrong technology for a specific task can prove to be fatal. The use of non-contact temperature devices is not an easy “off the shelf” pick but rather an option that demands knowledge of the infrared measurement theory as well as a complete understanding of the material under observation. The intention of this paper is to provide a practical understanding on the non-contact temperature measurement methods to the Aircraft Instrumentation Engineer who has not benefited from the use of this exiting technology.

New Quasi-optical sensor technology, based on the millimetre and submillimetre band of the electromagnetic spectrum, is actually being implemented for many commercial and scientific applications such as remote sensing, astronomy, collision avoidance radar, etc. These novel devices make use of integrated active and passive structures usually as planar arrays. The electromagnetic design and computer simulation of these new structures requires novel numerical techniques. The Finite Difference Time Domain method (FDTD) is well suited for the electromagnetic analysis of integrated devices using active non-linear elements, but is difficult to use for large and/or periodic structures. A rigorous revision of this popular numerical technique is performed in order to permit FDTD to model practical quasi-optical devices. The system impulse response or discrete Green's function (DGF) for FDTD is determined as a polynomial then the FDTD technique is reformulated as a convolution sum. This new alternative algorithm avoids Absorbing Boundary Conditions (ABC's) and can save large amounts of memory to model wire or slot structures. Many applications for the DGF can be foreseen, going beyond quasi-optical components. As an example, the exact ABC based on the DGF for FDTD is implemented for a single grid wall is presented. The problem of time domain analysis of planar periodic structures modelling only one periodic cell is also investigated. Simple Periodic Boundary Conditions (PBC) can be implemented for FDTD, but they can not handle periodic devices (such as phased shift arrays or dichroic screens) which produce fields periodic in a 4D basis (three spatial dimensions plus time). An extended FDTD scheme is presented which uses Lorentz type coordinate transformations to reduce the problem to 3D. The analysis of non-linear devices using FDTD is also considered in the thesis. In this case, the non linear devices are always model using an equivalent lumped element circuit. These circuits are introduced into the FDTD grid by means of the current density following an iterative implicit algorithm. As a demonstration of the technique a quasi-optically feed slot ring mixer with integral lens is designed for operation at 650 GHz.

The diploma work is focused on situation and function of Czech mobile providers market. The theoretical background is based on Ronald Coase's findings. The functionality of theoretical hypothesis is verified and further discussed on the basis of foreign telecommunication markets. Different real economics provide valuable experience concerning identification of possible assets and problems. The acquired information is consequently used for analysis of Czech mobile market. Next to the evaluation of the current situation the focus is given to the planned auction of frequencies. Conditions of this auction are described and the potential influence to future Czech mobile providers market is monitored.

An analysis of the state interventions into a broadcasting market will be the aim of this thesis. A state is in the most of countries represented by a special broadcasting market commission. In my thesis I will focus on the commission's behaviour. In the first part of my thesis I would like to consider a theoretical background, history and actual legislation of the electromagnetic spectrum regulation, particularly the legislation of both types of regulation -- structural and content regulation. Conclusions reached will be applied to the situation in the Czech Republic. The thesis should answer questions as whether the members of the commissions are objective, independent in their decision-making and behave within the defined legal frame. Acting of the Czech commission will be analyzed on the example of "Radio Wave affair". This radio station was taken from analog broadcast after the pressure from the Council of the Czech Radio.

Orientador: Juliano Maurício de Carvalho / Banca: Marcos Americo / Banca: Ivete Cardoso Roldão / Resumo: A presente dissertação resulta de uma pesquisa descritiva e documental, de cunho exploratório, sobre a televisão digital e sua oportunidade de democratização da comunicação, neste caso, analisando especificamente o espectro da televisão. A substituição do sinal televisivo analógico pelo sinal digital acarreta mudanças significativas no setor de telecomunicações, em especial, por impor nova regulamentação e propor redefinição quanto ao uso do espectro eletromagnético nacional, que pertence ao Estado brasileiro, responsável pela concessão ou autorização de seu uso. A partir da adaptação do espectro à realidade digital, o Estado brasileiro teve a chance de modificar o sistema televisivo nacional, incluindo operadores e novos serviços, ou ainda excluindo os mesmos. Diante desse cenário, esta pesquisa se propõe a identificar como se deu a construção da gestão do espectro eletromagnético durante o processo de digitalização dos sinais de TV e as mudanças ocorridas nos conjuntos legislativos relativas ao espectro e à digitalização dos sinais, que afetam Estado, grupos de mídia e a sociedade civil. Entre as conclusões, fica claro que o Estado preferiu realizar a manutenção do Sistema Televisivo Nacional, sem a abertura de novos espaços e novos canais privados ou mistos. O Estado optou ainda por cercear espaço para uso próprio e fundamentar as bases para um aumento qualitativo e quantitativo de operadores da televisão aberta, rumo a preceitos incluídos na luta pelo Direito à Comunicação e da Democratização da Comunicação. / Abstract: This work results from an investigation of documents and exploratory on digital television and its opportunity to democratize comunications in this case, examining specifically the television spectrum. The replacement of analogue television signal by the digital signal causes significant changes in the telecommunications industry, in particular, by imposing new rules andn propose redefinig on the national use of the electromagnetic spectrum, which belongs to the Brazilian State. From the adaptation to the reality of the digital spectrum, the Brazilian State had a change to modify the national television system, including operators and new services, or excluding them. Given this scenario, this research aims to identify how was the construction management of the electromagnetic spectrum during the process of digitalization of TV signals and changes in legislative assemblies on the spectrum and the digitalization os signals that affect the state, media groups and civil society. Among the findings, it is clear that the State chose to perform the maintenance of the National Television System, without opening up new spaces and new private channels or mixed. The State has opted to restrict space for their own use and to explain the basis for a qualitative and quantitative increase of operators of broadcast television, toward precepts included in the fight for the Right to Communication and Democratization of Communication. / Mestre

Made available in DSpace on 2014-06-11T19:30:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-04-04Bitstream added on 2014-06-13T19:00:21Z : No. of bitstreams: 1 xavier_rs_me_bauru.pdf: 1263710 bytes, checksum: c282218c01d80cac3c19f19411efb454 (MD5) / Universidade Estadual Paulista (UNESP) / A presente dissertação resulta de uma pesquisa descritiva e documental, de cunho exploratório, sobre a televisão digital e sua oportunidade de democratização da comunicação, neste caso, analisando especificamente o espectro da televisão. A substituição do sinal televisivo analógico pelo sinal digital acarreta mudanças significativas no setor de telecomunicações, em especial, por impor nova regulamentação e propor redefinição quanto ao uso do espectro eletromagnético nacional, que pertence ao Estado brasileiro, responsável pela concessão ou autorização de seu uso. A partir da adaptação do espectro à realidade digital, o Estado brasileiro teve a chance de modificar o sistema televisivo nacional, incluindo operadores e novos serviços, ou ainda excluindo os mesmos. Diante desse cenário, esta pesquisa se propõe a identificar como se deu a construção da gestão do espectro eletromagnético durante o processo de digitalização dos sinais de TV e as mudanças ocorridas nos conjuntos legislativos relativas ao espectro e à digitalização dos sinais, que afetam Estado, grupos de mídia e a sociedade civil. Entre as conclusões, fica claro que o Estado preferiu realizar a manutenção do Sistema Televisivo Nacional, sem a abertura de novos espaços e novos canais privados ou mistos. O Estado optou ainda por cercear espaço para uso próprio e fundamentar as bases para um aumento qualitativo e quantitativo de operadores da televisão aberta, rumo a preceitos incluídos na luta pelo Direito à Comunicação e da Democratização da Comunicação. / This work results from an investigation of documents and exploratory on digital television and its opportunity to democratize comunications in this case, examining specifically the television spectrum. The replacement of analogue television signal by the digital signal causes significant changes in the telecommunications industry, in particular, by imposing new rules andn propose redefinig on the national use of the electromagnetic spectrum, which belongs to the Brazilian State. From the adaptation to the reality of the digital spectrum, the Brazilian State had a change to modify the national television system, including operators and new services, or excluding them. Given this scenario, this research aims to identify how was the construction management of the electromagnetic spectrum during the process of digitalization of TV signals and changes in legislative assemblies on the spectrum and the digitalization os signals that affect the state, media groups and civil society. Among the findings, it is clear that the State chose to perform the maintenance of the National Television System, without opening up new spaces and new private channels or mixed. The State has opted to restrict space for their own use and to explain the basis for a qualitative and quantitative increase of operators of broadcast television, toward precepts included in the fight for the Right to Communication and Democratization of Communication.

As the amount of study into the terahertz (THz) region of the electromagnetic spectrum steadily increases, the parallel plate waveguide has emerged as a simple and effective fixture to perform many experiments. The ability to concentrate THz radiation into a small area or volume enables us to analyze smaller samples and perform more repeatable measurements, which is essential for future research. While the fundamental physics of PPW transmission are understood mathematically, the practical knowledge of building such a fixture for the THz domain and taking measurements on it with a real system needs to be built up through experience. In this thesis, multiple PPW configurations are built and tested. These include waveguides of different lengths and opening heights, using lenses and antennas to focus and collect radiation from the input and output, and different amounts of polish on the waveguide surface. A basic resonator structure is also built and measured as a proof of concept for future research. The two most useful propagation modes through the waveguide, the lowest order transverse magnetic (TEM) and transverse electric (TE) modes, were characterized on all of the setups. Additionally, a flexible fixture was designed and measured which will allow future work in the THz field to be much more reliable and repeatable.

I takt med att tekniken för mikroelektromekaniska system utvecklas uppkommer det nya områden för tillämpning. Ett område är inom gassensorer där icke-dispersiv infraröd strålning används genom att mäta absorptionen hos olika gaser för att bestämma mängden av en specifik gas i luften. I detta projekt var målet att använda en vågledare med en infraröd lysdiod på ena sidan och en fotodetektor på andra sidan där vågledaren har som uppgift att utsätta ljuset för maximal mängd koldioxid innandet träffar fotodetektorn. Motiveringen för valet av koldioxid var att det är en gas som har stor påverkan på både klimat och arbetsmiljö. Metoden som ansågs vara bäst för placeringen av tidigare nämnda komponenter var att använda programmerbara rörelseenheter som kallas hexapod som består av sex ben som möjliggör tredimensionella rörelser och rotationer kring varje axel i det kartesiska koordinatsystemet. Experiment där elektromagnetiska störningar från lysdioden undersöktes vilket visade att det förekom elektromagnetisk störning samt att lysdioden påverkade fotodetektorn genom spridning trots att lysdiod och fotodetektor inte var vända mot varandra. / As the technology for microelectromechanical systems develops, new areas of application are emerging. One area is within gas sensors where non-dispersive infrared radiation is used by measuring the absorption of various gases to determine the concentration of a specific gas in the air. In this project, the goal was to use a waveguide with an infrared LED on one side and a photodetector on the other side where the waveguide has the task of exposing the light to the maximum amount of carbon dioxide before it hits the photodetector. The reason for the choice of carbon dioxide was that it is a gas that has a great impact on both the climate and the working environment. The method that was considered to be best for the placement of the aforementioned components was to use programmable motion units called hexapods which consist of six struts that enable three-dimensional movements and rotations around each axis of the Cartesian coordinate system. Experiments in which the electromagnetic interference from the LED were investigated showed that there was electromagnetic interference and that the LED affected the photodetector by scattering, even though the LED and photodetector were not facing each other.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Over the last years, the wireless broadband access has achieved a tremendous success. With that, the telecommunications industry has faced very important changes in terms of technology, heterogeneity, kind of applications, and massive usage (virtual data tsunami) derived from the introduction of smartphones and tablets; or even in terms of market structure and its main players/actors. Nonetheless, it is well-known that the electromagnetic spectrum is a scarce resource, being already fully occupied (or at least reserved for certain applications). Tra- ditional spectrum markets (where big monopolies dominate) and static spectrum management originated a paradoxal situation: the spectrum is occupied without actually being used! In one hand, with the global transition from analog to digital Television (TV), part of the spectrum previously licensed for TV is freed and geographically interleaved, originating the consequent Television White Spaces (TVWS); on the other hand, the direct communications between devices, commonly referred as Device-to-Device (D2D) communications, are attracting crescent attention by the scientific community and industry in order to overcome the scarcity problem and satisfy the increasing demand for extra capacity. As such, this thesis is divided in two main parts: (a) Spectrum market for TVWS: where a SWOT analysis for the use of TVWS is performed giving some highlights in the directions/actions that shall be followed so that its adoption becomes effective; and a tecno-economic evaluation study is done considering as a use-case a typical European city, showing the potential money savings that operators may reach if they adopt by the use of TVWS in a flexible market manner; (b) D2D communications: where a neighbor discovery technique for D2D communications is proposed in the single-cell scenario and further extended for the multi-cell case; and an interference mitigation algorithm based on the intelligent selection of Downlink (DL) or Uplink (UL) band for D2D communications underlaying cellular networks. A summary of the principal conclusions is as follows: (a) The TVWS defenders shall focus on the promotion of a real-time secondary spectrum market, where through the correct implementation of policies for protection ratios in the spectrum broker and geo-location database, incumbents are protected against interference; (b) It became evident that an operator would recover its investment around one year earlier if it chooses to deploy the network following a flexible spectrum market approach with an additional TVWS carrier, instead of the traditional market; (c) With the proposed neighbor discovery technique the time to detect all neighbors per Mobile Station (MS) is significantly reduced, letting more time for the actual data transmission; and the power of MS consumed during the discovery process is also reduced because the main processing is done at the Base Station (BS), while the MS needs to ensure that D2D communication is possible just before the session establishment; (d) Despite being a simple concept, band selection improves the gains of cellular communications and limits the gains of D2D communications, regardless the position within the cell where D2D communications happen, providing a trade-off between system performance and interference mitigation. / Nos Ãltimos anos, o acesso de banda larga atingiu um grande sucesso. Com isso, a indÃstria das telecomunicaÃÃes passou por importantes transformaÃÃes em termos de tecnologia, heterogeneidade, tipo de aplicaÃÃes e uso massivo (tsunami virtual de dados) em consequÃncia da introduÃÃo dos smartphones e tablets; ou atà mesmo na estrutura de mercado e os seus principais jogadores/atores. PorÃm, à sabido que o espectro electromagnÃtico à um recurso limitado, estando jà ocupado (ou pelo menos reservado para alguma aplicaÃÃo). O mercado tradicional de espectro (onde os grandes monopÃlios dominam) e o seu gerenciamento estÃtico contribuÃram para essa situaÃÃo paradoxal: o espectro està ocupado mas nÃo està sendo usado! Por um lado, com a transiÃÃo mundial da TelevisÃo (TV) analÃgica para a digital, parte do espectro anteriormente licenciado para a TV à libertado e geograficamente multiplexado para evitar a interferÃncia entre sinais de torres vizinhas, dando origem a ÂespaÃos em branco na frequÃncia da TV ou Television White Spaces (TVWS); por outro lado, as comunicaÃÃes diretas entre usuÃrios, designadas por comunicaÃÃes diretas Dispositivo-a-Dispositivo (D2D), està gerando um crescente interesse da comunidade cientÃfica e indÃstria, com vista a ultrapassar o problema da escassez de espectro e satisfazer a crescente demanda por capacidade extra. Assim, a tese està dividida em duas partes principais: (a) Mercado de espectro eletromagnÃtico para TVWS: onde à feita uma anÃlise SWOT para o uso dos TVWS, dando direÃÃes/aÃÃes a serem seguidas para que o seu uso se torne efetivo; e um estudo tecno-econÃmico considerando como cenÃrio uma tÃpica cidade Europeia, onde se mostram as possÃveis poupanÃas monetÃrias que os operadores conseguem obter ao optarem pelo uso dos TVWS num mercado flexÃvel; (b) ComunicaÃÃes D2D: onde uma tÃcnica de descoberta de vizinhos para comunicaÃÃes D2D à proposta, primeiro para uma Ãnica cÃlula e mais tarde estendida para o cenÃrio multi-celular; e um algoritmo de mitigaÃÃo de interferÃncia baseado na seleÃÃo inteligente da banda Ascendente (DL) ou Descendente (UL) a ser reusada pelas comunicaÃÃes D2D que acontecem na rede celular. Um sumÃrio das principais conclusÃes à o seguinte: (a) Os defensores dos TVWS devem-se focar na promoÃÃo do mercado secundÃrio de espectro electromagnÃtico, onde atravÃs da correta implementaÃÃo de politicas de proteÃÃo contra a interferÃncia no broker de espectro e na base de dados, os usuÃrios primÃrio sÃo protegidos contra a interferÃncia; (b) Um operador consegue recuperar o seu investimento aproximadamente um ano antes se ele optar pelo desenvolvimento da rede seguindo um mercado secundÃrio de espectro com a banda adicional de TVWS, em vez do mercado tradicional; (c) Com a tÃcnica proposta de descoberta de vizinhos, o tempo de descoberta por usuÃrio à significativamente reduzido; e a potÃncia consumida nesse processo à tambÃm ela reduzida porque o maior processamento à feito na EstaÃÃo RÃdio Base (BS), enquanto que o usuÃrio sà precisa de se certificar que a comunicaÃÃo direta à possÃvel; (d) A seleÃÃo de banda, embora seja um conceito simples, melhora os ganhos das comunicaÃÃes celulares e limita os das comunicaÃÃes D2D, providenciando um compromisso entre a performance do sistema e a mitigaÃÃo de interferÃncia.