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GRAPHENE BASED RF/MICROWAVE IMPEDANCE SENSING and Low Loss conductor for RF applicationsIramnaaz, Iramnaaz January 2011 (has links)
No description available.
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Design and Simulation of Multi-Frequency Global Navigation Satellite System Receiver Radio Frequency Front-EndViswanatha, Raghunath 29 December 2008 (has links)
No description available.
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Zwischennutzungen in BerlinOtto, Benjamin 18 January 2016 (has links)
Die vorliegende Arbeit untersucht Zwischennutzungen in Berlin aus Akteurssicht. Zwischennutzungen sind von Beginn an und von allen Beteiligten als temporär gedacht. Sie finden in bzw. auf leerstehenden Immobilien statt und sind mit einer Nutzungsänderung verbunden, d.h. eine Zwischennutzung unterscheidet sich sowohl von der vorigen Nutzung der Immobilie als auch von der geplanten neuen Nutzung. Ausgehend von dieser erarbeiteten Definition wird das Phänomen empirisch am Beispiel Berlins untersucht. Die mehr als 100 recherchierten Berliner Zwischennutzungsprojekte konzentrieren sich räumlich auf attraktive innerstädtische Lagen. Zwischennutzungsverträge erlauben finanzschwachen Akteuren, Grundstücke günstig zu mieten. Sie akzeptieren dafür Einschränkungen wie die begrenzte Nutzungsdauer und kurze Kündigungsfristen. Es konnten fünf Motivationstypen von Zwischennutzern erarbeitet werden: Für „Pioniere“ und „Profi-Zwischennutzer“ steht der ökonomische Aspekt bei der Zwischennutzung im Vordergrund. Das Hauptmotiv von „ehrenamtlichen, subkulturellen und künstlerischen Zwischennutzern“ ist dagegen die eigene Selbstverwirklichung. Die meisten Nutzer streben die langfristige Sicherung ihres Projektes an. Die Grundstückseigentümer handeln überwiegend ökonomisch-rational. Zwischennutzungen sind aus ihrer Sicht eine sinnvolle Lösung, wenn das Nutzungskonzept passend ist und die Mieteinnahmen den Aufwand und das Risiko einer kurzfristigen Vermietung übersteigen. Gute persönliche Beziehungen werden sowohl von Nutzer- als auch von Eigentümerseite als wichtige Komponenten für den Abschluss eines Zwischennutzungsvertrags gesehen. In vielen Fällen finden Zwischennutzungsprojekte in Berlin auf Grundstücken statt, auf denen aus stadtplanerischer Sicht kein Handlungsbedarf besteht. Die Planungsämter arbeiten überwiegend mit Duldungen und Befreiungen. Das Baurecht auf Zeit wird nicht angewendet, informelle Instrumente kommen nur vereinzelt zur Anwendung. / This work examines temporary uses in Berlin and the involved participants. Temporary (or interim) uses are seen as temporary from the beginning and by all involved stakeholders. They take place on brownfield sites or in abandoned buildings, and are always associated with a change in use. A temporary use differs both from the previous use of the land as well as the proposed new use. Based on this definition, the phenomenon is investigated empirically in Berlin. Most temporary uses arise in or near the urban centre. About half of the temporarily used property is located in the three inner-city districts of Mitte, Prenzlauer Berg and Friedrichshain. Financially weak actors have to pay lower rents for these properties because of temporary use contracts. In return they have to accept short periods of notice and other limitations. Based upon their motivation, five types of temporary users have been identified: For “pioneers” and “professional temporary users”, the economic aspect is most important. The main motive of “voluntary, subcultural and artistic temporary users”, however, is self-fulfilment. Although the users make short-term leases, most of them are aiming for long-term security for their projects. The landlords act predominantly economically and rationally. In their opinion temporary uses are good solutions if the concept fits and the rental income exceeds the cost and the risk of short-term rent. Both temporary users and landlords see good personal relationships as an important component for the signing of a temporary use contract. In many cases temporary uses in Berlin are located on properties where no action for urban planning is required. The planning authorities mainly deal with them by way of toleration and immunities. The “Baurecht auf Zeit” (temporary building law) is not applied and informal instruments are only sporadically applied.
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Détection à distance d’électroniques par l’intermodulation / Remote detection of electronics by intermodulationMartorell, Alexandre 23 July 2018 (has links)
Électromagnétisme, sécurité et guerre électronique sont étroitement liés depuis des décennies. Leur association rassemble des applications de surveillance radar, de neutralisation de systèmes électroniques ou de détection d’électroniques cachées. Aujourd’hui, la multiplication des EEI (Engins Explosifs Improvisés) aussi bien sur les théâtres d’opération que dans les milieux urbains conduit à la nécessité de leur détection. Les travaux de cette thèse peuvent entrer dans cette thématique et proposent une nouvelle alternative qui permet de mettre en évidence la présence de récepteurs RF cachés. Le radar non-linéaire est particulièrement adapté à la détection de dispositifs contenant des métaux et des semi-conducteurs (électroniques). Une technique populaire consiste à transmettre une seule fréquence f1 et à recevoir la seconde harmonique générée par la cible. Une autre technique, moins courante, consiste à transmettre deux fréquences, f1 et f2, et à recevoir les produits d'intermodulation d’ordre 3 (2f1 - f2 et 2f2 - f1). Un état de l’art approfondi des systèmes radars non-linéaires est effectué dans un premier chapitre avec une comparaison de leurs caractéristiques. Dans un second chapitre, un banc de test en mode conduit est développé permettant la mesure de l’IM3 réfléchi d’une cible RF. Ainsi des analyses et des ordres de grandeurs seront connus aidant au développement du radar. Dans le chapitre 3, Le démonstrateur du radar à IM3 est développé. Un large panel de systèmes RF, commerciaux ou non, susceptibles d’être trouvé dans des milieux opérationnels est mis sous test. Leur détection va permettre de valider la technique de récupération de l’IM3. Un nouveau bilan de liaison réaliste du radar IM3 est mis en place afin d’estimer la portée de détection réelle du radar, pour différentes cibles RF. Dans le dernier chapitre les travaux s’orientent sur l’identification et la classification d’une cible RF. L’étude porte sur la possibilité d’extraire tous paramètres pouvant aider à une classification (évaluation du danger) de récepteurs RF dans un milieu opérationnel. Le travail de recherche présenté dans ce manuscrit contribue à l’amélioration des techniques de détection d’électroniques cachées. Un protocole de détection a été proposé décrivant les faits et gestes du radar IM3. Il inclut un balayage en fréquence puis en puissance. Les premiers tests ont été effectués sur un Talkie-Walkie démontrant la possibilité de détecter sa bande passante via la réémission d’IM3, à plus de 2 m. La répétabilité des tests sur un panel élargi de récepteurs RF valide le protocole de détection et l’intérêt du radar IM3. Une puissance d’émission du radar IM3 de 40 dBm, à une fréquence d’IM3 de 400 MHz, peut potentiellement détecter un récepteur à 80 m. Enfin dans un dernier travail exploratoire nous avons démontré que, par l’observation de la réponse de l’IM3 réfléchi suite à un balayage en puissance, le radar IM3 peut ajouter de nouveaux critères d’identification discriminant les récepteurs détectés entre eux. / Electromagnetism, security and electronic warfare have been closely linked for decades. Their association gathers applications of radar surveillance, neutralization of electronic systems or detection of hidden electronics. Today, the multiplication of IEDs (Improvised Explosive Devices) both in theatres of operation and in urban environments leads to the need for their detection. The works of this thesis can enter into this theme and propose a new alternative that allows to highlight the presence of hidden RF receivers. The nonlinear radar is particularly suitable for detecting devices containing metals and (electronic) semiconductors. A popular technique is to transmit a single frequency f1 and receive the second harmonic generated by the target. Another less common technique consists of transmitting two frequencies, f1 and f2, and receiving intermodulation products of order 3 (2f1 - f2 and 2f2 - f1). An in-depth state of the art of nonlinear radar systems is made in a first chapter with a comparison of their characteristics. In a second chapter, an inductive test bench is developed to measure the reflected IM3 of an RF target. Thus analyses and orders of magnitude will be known helping the development of radar. In chapter 3, the IM3 radar demonstrator is developed. A wide range of RF systems, commercial and non-commercial, that may be found in operational environments are being tested. Their detection will validate the IM3 recovery technique. A new realistic IM3 radar link budget is implemented to estimate the actual radar detection range for different RF targets. In the last chapter the work focuses on the identification and classification of an RF target. The study focuses on the possibility of extracting all parameters to assist in a classification (hazard assessment) of RF receptors in an operational environment. The research work presented in this manuscript contributes to the improvement of hidden electronic detection techniques. A detection protocol was proposed describing the actions of the IM3 radar. It includes a frequency scan and then a power scan. The first tests were carried out on a walkie-talkie demonstrating the possibility of detecting its bandwidth via IM3 retransmission, at more than 2 m. The repeatability of the tests on an extended panel of RF receivers validates the detection protocol and the interest of the IM3 radar. An IM3 radar transmission power of 40 dBm, at an IM3 frequency of 400 MHz, can potentially detect a receiver at 80 m. Finally in a final exploratory work, we demonstrated that by observing the IM3 response reflected following a power scan the IM3 radar can add new identification criteria that discriminate the hidden receivers detected between them.
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The Promise of Wireless Interfaces Onboard SpacecraftPlummer, Chris, Magness, Rodger 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Wireless interfaces are becoming ubiquitous in terrestrial applications ranging from local area networking in business and commercial environments to large scale factory automation and process control. The pressure to develop these wireless interfacing techniques has come from the need to reduce cabling, reduce installation costs, and make it easier to extend network infrastructures. Concerns about electromagnetic compatibility, safety, reliability, and security have lead to the development of techniques and protocols that enable such wireless interfaces to be operated in electromagnetically harsh environments, without generating unacceptable interference, and providing reliable, dependable and secure data communications. On the face of it, the use of wireless interfaces onboard spacecraft looks like a good way of reducing the spacecraft harness mass and bulk. However, recent work by the European Space Agency has shown that, while harness reduction will undoubtedly be one benefit of using wireless interfaces, they offer many other benefits that will be more significant in the near future. Amongst these are significant advantages during integration and testing, the ability to retrofit and upgrade facilities, and cable replacement in moving structures such as robotic arms. In this paper we briefly survey the benefits of wireless interface technologies for spacecraft onboard use, and identify the challenges involved in adapting them for flight use. We then look at the considerations that should be taken into account in establishing the financial case for developing wireless interface technologies for flight applications.
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Fuktstyrning av inomhusklimatet på Skoklosters slott : En utvärdering av avfuktning, skyddsvärme och fuktstyrd ventilationEriksson, Rickard January 2016 (has links)
Moisture control of the indoor climate in Skokloster castle Rickard Eriksson Moisture control aims to reduce the risks associated with high relative humidity (RH) to avoid the emergence and growth of mold. In historic buildings with little or no demand for thermal comfort there are, to lower RH, mainly three active climate actions. These are heating, dehumidification and adaptive ventilation. The methods have been used in Skokloster castle (an unheated baroque castle between Uppsala and Stockholm) for three years to enable decision making of what climate control strategy that can prevent mold growth in a energy efficient way. Each action lasted for a year in three different case study rooms. To see the effect of the actions, three reference rooms with no actions were used. Temperature and RH was measured for all years and rooms. In the case study rooms energy use was registered. The result shows that the need for active climate control has been low, which can be shown by studying the energy use. The energy use is generally low for all actions and should not be crucial for the future choices. The result is in many ways difficult to interpret, but it shows that it would be too risky not to apply moisture control in Skokloster castle. An important conclusion is that it is largely the exceptions that have navigated the equipment and that the exceptions therefore should navigate the choice of the climate control strategy.
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CONCEPTUAL DESIGN OF CENTIMETER ACCURACY LOCAL POSITIONING SYSTEMAnnamraju, Venu, Kosbar, Kurt 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This project investigates the feasibility of position detection in an office or industrial setting. The objective is to design a low-cost positioning system that uses the unlicensed 5.7 GHz ISM band, with centimeter accuracy and limited range. During the conceptual design phase of the system, indoor channel models will be investigated to determine which of a variety of architectures will be useful. For triangulating the position, an array of widely spaced stationary receivers and a mobile transmitter is proposed.
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Shallow Water Training RangeReid, Robert 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / During the cold war, undersea warfare (USW) was perceived as a large-area, deep-water operation. The need for USW has recently shifted to the shallow water, littoral environment. Consequently, US naval forces must train to operate in these littoral environments where regional conflicts are most likely to occur. In light of these requirements the Shallow Water Training Range (SWTR) has been initiated. Telemetry is used in the following areas of SWTR: fiber optic, microwave, RF and underwater. Only phase 1 of 8 phases of the program is executing therefore SWTR is a good opportunity for telemetry industry involvement.
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RANGE TELEMETRY IMPROVEMENT AND MODERNIZATIONChalfant, Timothy A., Irving, Charles E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The system throughput capacities of modern data systems exceed the bit rate capacity of
current range telemetry capabilities. Coupling this with the shrinking spectrum allocated
for telemetry results in a serious problem for the Test, Training, and Space telemetry users.
Acknowledging this problem, the Department of Defense (DoD) has embarked on an
aggressive improvement and modernization program that will benefit both the government
and commercial range providers and users. The ADVANCED RANGE TELEMETRY
(ARTM) program was created and funded by the Central Test and Evaluation Investment
Program (CTEIP) under the Office of the Secretary of Defense, Undersecretary for
Acquisition and Technology to address this problem. The ARTM program goals are to
improve the efficiency of spectrum usage by changing historical methods of acquiring
telemetry data and transmitting it from systems under test to range customers. The program
is initiating advances in coding, compression, data channel assignment, and modulation.
Due to the strong interactions of these four dimensions, the effort is integrated into a single
focused program. This paper describes the ARTM program and how academia research,
emerging technology, and commercial applications will lay the foundation for future
development.
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Modeling, design, fabrication and characterization of miniaturized passives and integrated EM shields in 3D RF packagesSitaraman, Srikrishna 07 January 2016 (has links)
An innovative structure for thin-film band-pass filters was proposed and analyzed. This structure was employed in the design, fabrication, and development of 3D IPD diplexers on glass substrates with double-side metallization electrically connected by through-vias. Through modeling, design, fabrication and characterization of the WLAN 3D IPD glass diplexers, the proposed filter structure was shown to enable miniaturized and high-performance RF passives. Further, component-level shield structures were developed to provide electromagnetic interference isolation between thin-film passives that are placed less than 100 µm apart. Glass substrates were designed, fabricated and characterized to demonstrate the shield effectiveness of metallized trench and via-array-based shields. The integration of such shields in miniaturized WLAN RF modules enables up to 60dB EM isolation in the frequency range of 1- 20GHz. Advanced RF module technologies based on 3D IPAC concept were designed and demonstrated with ultra-thin low-loss organic and glass substrates, integrating the proposed WLAN actives with miniaturized diplexer and EM shields. Double-side integration of such high-performance components on ultra-thin glass substrates enables up to 8x volume miniaturization including more than 3x reduction in area. Thus, the advanced components demonstrated in this research, vis-a-vis miniaturized diplexers and component-level EMI shields; integrated with actives in ultra-thin glass substrates using the 3D IPAC concept, can enable highly-miniaturized smart systems with multiband wireless communication capabilities.
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