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Cloppenburg, Jürgen. "The regulation of global mobile personal communications by satellite : a comparative analysis of regulations, policy and perspectives in the European Union, in particular Germany, and the United States." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31153.
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This thesis analyses the current regulatory regimes in the European Union---in particular Germany---and the United States governing the authorization of global mobile personal communications by satellite (GMPCS).Current satellite licensing regimes fail to take into account the international character of satellite telecommunications. The reliance on a national public interest standard does not properly address the interests of the community of states, industry and consumers and is not suitable to meet the aspirations of international space law. The international harmonization of frequencies and international standardization are indispensable for the introduction of these new services. The establishment of an international communications regulator with the power to adopt binding decisions if required is the most suitable way to address these problems. However, the development of an international public interest standard with clear policy objectives will be hard to achieve.
With regard to the different aspects of ground segment licensing, a gradual approach is the best way to balance the different interests and concerns in this field. The International Telecommunications Union GMPCS MoU and the development of European regulations show a feasible way to achieve a regulatory regime that facilitates the introduction of these new services. Lighter regulations, possibly the introduction of one stop shopping procedures, mutual recognition of licenses and the introduction of general authorizations are measures that can and should be taken at the international level. The interdependence of earth and space segment licensing may lead to the understanding that some aspects of earth segment licensing should also be regulated at international level.
The question will be whether States, industry and users are able to reconcile their interests and the sometimes opposing trends of international cooperation and international competition for the benefit of "all mankind".
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Potschka, Christian. "Towards a market in broadcasting : a comparative analysis of British and German communications policy." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6324.
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Political structures and the evolution of late capitalism in liberal Western democracies lend a common frame to the development of national media systems. However, whereas media policy from the post-war period to the mid-1980s was largely driven by socio-political concerns and coextensive with policy for public service television, this model has been vehemently challenged. Key factors were the convergence of erstwhile-separated industries and infrastructures, as well as the ambitions of the corporate sector and governments alike, to benefit from the economic opportunities offered by the communications revolution. By assessing the changing relationship between the role of the state, economic structures and technological innovation, this research investigates these processes in the UK and Germany. Both countries have the two key public service systems but also feature striking differences such as the antithetic political systems and democratic processes (majoritarian vs. consensus democracy). The basic assumption suggests that a genuine understanding of contemporary developments is only possible if political/economic as well as historic/sociological perspectives are incorporated into the holistic approach applied. Thereby this study gives consideration to key processes and events which have determined transitions between communications policy paradigms and regulatory regimes. Given the Anglo-Saxon tradition of regulating, key processes and events in the UK are often indicated by the appointment and report of a committee of enquiry. For the purpose of this study the most crucial of these is the Committee on Financing the BBC (1986), which first applied market-driven politics onto British broadcasting, and whose recommendations still serve as a blueprint for current communications policy-making. In Germany the KtK Report (1974) formed the basis for decisive reforms in broadcasting and communications. Apart from that, however, Germany features the characteristic of administering state interventions in as detailed a manner as possible through legislation. Of central importance are, therefore, the rulings of the Federal Constitutional Court, which continuously set decisive parameters for the development of the broadcasting system. The thesis follows two driving themes which have been identified as crucial in terms of the comparative dimension and are elaborated continuously in more detail. First, the focus is on the interdependencies between public and private sector. Second, implications and responses of the central vis-à-vis federal characteristic of state formation are investigated. In doing so, the thesis draws on vast sources of archival documents as well as exclusive material from a series of elite interviews with a purposively-selected sample of very high-level sources, including Chairmen, Director-Generals, ministers, very senior civil servants and so on. The thesis demonstrates how communications policy-making is carried out in both countries and how these processes are determined by national regulatory frameworks which are rooted within the borders of the nation state. As such the research findings have broader implications for commercial and public sector regulation.
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Kozak, Nadine Irène. "On the last mile the effects of telecommunications regulation and deregulation in the rural western United States and Canada /." Diss., [La Jolla] : University of California, San Diego, 2010. http://wwwlib.umi.com/cr/ucsd/fullcit?p3390098.
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Thesis (Ph. D.)--University of California, San Diego, 2010.Title from first page of PDF file (viewed Feb. 22, 2010). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 421-450).
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Knutsson, Mikael. "Compliance with the General Data Protection Regulation: an exploratory case study on business systems’ adaptation." Thesis, KTH, Medieteknik och interaktionsdesign, MID, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209772.
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Current moves into a heavily digitalized era has led to a phase where our privacy is being eroded as we hand over our personal data to organizations and their systems. At the same time, the applicable laws to give security to the individuals have failed to incorporate these legal developments. However, in April 2016 the European Union proposed a change to a new regulation called the General Data Protection Regulation (GDPR). The GDPR will be implemented and start to apply in May 2018, thus the main purpose of this study was to investigate how organizations can adapt to changing regulations on how personal data should be stored and managed, and what the key tension points are within specifically closed IT-systems. The goal of the GDPR and this study on its feature implementation is to guarantee the EU citizens their right to privacy. Through an exploratory case study involving an in-depth analysis of two closed IT-systems this study develops a broader understanding on how organizations should adapt their daily businesses in order to be fully compliant with the new bylaws. This study identifies four critical issues which are used to discuss how the new bylaws could affect the EU citizens’ privacy. To accomplish this and open up for further investigation within the field of data privacy laws - four different propositions to modifications were suggested.Den aktuella övergången till en omfattande digitaliserad tid har lett till en fas där vår integritet går förlorad då vi överlämnar vår personliga information till organisationer och deras system. Samtidigt har de tillämpade datalagarna med syfte att skydda individen misslyckats med att införliva denna utveckling. Därför har den Europeiska Unionen i april 2016 föreslagit en förändring till en ny reglering som får namnet Dataskyddsförordningen. Dataskyddsförordningen kommer blir implementerad och börja gälla i maj 2018 och därav var huvudsyftet med den här studien att undersöka hur organisationer bör anpassa sig till de nya riktlinjerna för hur personlig information bör lagras och hanteras samt vilka spänningspunkterna är för slutna IT-system. Målet med Dataskyddsförordningen och vad den här studien beaktade i dess kommande utförande är att garantera EU-medborgare rätten till sin integritet. Genom att utföra en undersökande fallstudie innehållandes en djupgående analys av två slutna IT-system har den här studien bidragit med en bredare förståelse för hur organisationer bör anpassa sina dagliga verksamhet för att vara helt medgörliga med Dataskyddsförordningen. Studien har identifierat fyra kritiska problem som har legat till grund för att diskutera hur den nya förordningen kommer påverka EU-medborgarnas rätt till sin integritet. För att göra det möjligt samt öppna upp för framtida undersökningar inom ramen för dataskyddslagar föreslogs fyra förslag på generella förändringar.
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Jana, Vimbai Lisa Michelle. "Adopting a harmonised regional approach to customs regulation for the tripartite free trade agreement." Thesis, University of the Western Cape, 2013. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8861_1380710167.
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Artusi, Denise. "5g mobile communications systems." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7563/.
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Un sistema mobile di comunicazione è un sistema di telecomunicazioni in cui è possibile mantenere la connessione o legame tra due o più utenti, anche nelle situazioni di mobilità totale o parziale degli stessi utenti. I sistemi radiomobili si stanno evolvendo dalla creazione del 1G (prima generazione) al 4G (quarta generazione). I telefoni di ogni generazione si differenziano in quattro aspetti principali : accesso radio, velocità di trasmissione dati, larghezza di banda e sistemi di commutazione.
In questa tesi si affronta il tema dei sistemi 5G , negli ambienti terrestri e satellitari , in quanto sono l'ultima evoluzione dei sistemi mobili .
Si introduce il passaggio dalla prima alla connessione di quarta generazione , al fine di capire perché 5G sta per cambiare la nostra vita . Quello che mi colpisce è il sito italiano www.Repubblica.it che dice : " con la nuova generazione 5 possiamo affidare le intere porzioni nette di vita". La tecnologia cellulare , infatti , ha cambiato radicalmente la nostra società e il nostro modo di comunicare . In primo luogo è cambiata la telefonia vocale , per poi trasferirsi all' accesso dati , applicazioni e servizi. Tuttavia , Internet non è stato ancora pienamente sfruttato dai sistemi cellulari. Con l'avvento del 5G avremo l'opportunità di scavalcare le capacità attuali di Internet . Il sistema di comunicazione di quinta generazione è visto come la rete wireless reale , in grado di supportare applicazioni web wireless a livello mondiale ( wwww ). Ci sono due punti di vista dei sistemi 5G : evolutivo e rivoluzionario. Dal punto di vista evolutivo, i sistemi 5G saranno in grado di supportare wwww permettendo una rete altamente flessibile come un Adhoc rete wireless dinamica ( DAWN ) . In questa visione tecnologie avanzate, tra cui antenna intelligente e modulazione flessibile , sono le chiavi per ottimizzare le reti wireless ad hoc. Dal punto di vista rivoluzionario, i sistemi 5G dovrebbe essere una tecnologia intelligente in grado di interconnettere tutto il mondo senza limiti . Un esempio di applicazione potrebbe essere un robot wireless con intelligenza artificiale .
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Schmitt, Michael Philipp. "ARQ systems for wireless communications." Phd thesis, [S.l. : s.n.], 2002. http://elib.tu-darmstadt.de/diss/000269.
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Parand, Farivar. "Cellular optical wireless communications systems." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270654.
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Edwards, David J. "Tracking systems for satellite communications." Thesis, University of Bristol, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379579.
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Hughes, Frank Lawrence Kingsman. "Multicast communications in distributed systems." Thesis, University of Newcastle Upon Tyne, 1986. http://hdl.handle.net/10443/2007.
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One of the numerous results of recent developments in communication networks and distributed systems has been an increased interest in the study of applications and protocolsfor communications between multiple, as opposed to single, entities such as processes and computers. For example, in replicated file storage, a process attempts to store a file on several file servers, rather than one. MUltiple entity communications, which allow one-to-many and many-to-one communications, are known as multicast communications. This thesis examines some of the ways in which the architectures of computer networks and distributed systems can affect the design and development of multicast communication applications and protocols. To assist in this examination, the thesis presents three contributions. First, a set of classification schemes are developed for use in the description and analysis of various multicast communication strategies. Second, a general set of multicast communication primitives are presented, unrelated to any specific network or distributed system, yet efficiently implementable on a variety of networks. Third, the primitives are used to obtain experimental results for a study ofintranetwork and internetwork multicast communications.
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Spracklen, Lawrence A. "SWAR systems and communications applications." Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369118.
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In recent years, the instruction sets of the majority of present day general purpose processors have been extended to include a variety of SWAR (SIMID Within A Register) instructions. These operations, which make possible the processing of multiple data elements with a single instruction, have been proven to facilitate the acceleration of a wide range of graphics and multimedia applications. The application of these instructions is not, however, just limited to this type of program, and current research is concerned with developing high performance implementations of a wide range of new applications. The initial part of this thesis presents a number of innovative strategies for accelerating previously un-addressed classes of application and illustrates that a significant degree of acceleration can frequently be achieved. However, for all of the applications analysed, several SWAR specific problems were repeatedly encountered. For the efficient operation of the implementation developed using these SWAR instructions, the organisation of the data to be processed is of critical importance and the required arrangement frequently fails to match that normally encountered in applications. SWAR ISEs (Instruction Set Extensions) usually contain functionality to address these problems, but it is shown by the author that this current functionality is insufficient and significantly curtails the performance achievable with these ISEs. The VMM (VIS Manipulation Matrix) was developed to address this problem and provide a methodology whereby the performance obtained using SWAR methodologies could be made significantly more independent of the underlying data organisation. The functionality of the VMM is presented and the effectiveness of this methodology is highlighted, by considering its application to a number of important algorithms. Finally, the feasibility of integrating the VMM into a general purpose processor is revealed, by highlighting its compatibility with the UltraSPARC processor.
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Taylor, Gregory. "Canadian broadcasting regulation and the digital television transition." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86874.
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This thesis examines the evolution of Canadian broadcasting regulation since the adoption of the 1991 Broadcasting Act with a specific focus on the digital television transition. For Canada, this technological shift exemplifies many of the greater changes in public policy in the last two decades: a faith in market mechanisms, light-touch regulation, co-regulatory approaches, and the powerful influence of new technologies. This dissertation will address the following central question: does the policy surrounding the transition to digital television broadcasting pose a challenge to traditional concerns of the role of broadcasting in Canadian democracy? Utilizing the approach of institutional political economy, this study is informed by primary government and industry documents and interviews conducted with key actors within Canadian broadcasting. This dissertation offers a unique contribution to knowledge in three areas: establishing clear parameters for the differences between policy and regulations in Canadian broadcasting; offering the first comprehensive study of the Canadian digital television transition; and analyzing the growth and impact of self and co-regulation in Canadian broadcasting policy. The results of this study speak to the power dynamics amid the range of actors involved in the Canadian policy process, the influence of new technologies, and the greater prevailing policy directions in broadcasting since the 1991 Broadcasting Act was adopted.Cette thèse examine l'évolution de la réglementation canadienne de la radiodiffusion depuis l'adoption de la Loi sur la radiodiffusion (fédérale) en 1991 en se concentrant plus particulièrement sur la transition à la télévision numérique. Pour le Canada, ce changement de cap est révélateur des grandes modifications que les politiques publiques ont connues dans les deux dernières décennies : une foi dans les mécanismes de marché, une réglementation en pointillé, des approches axées sur la coréglementation et la puissante influence des nouvelles technologies. La question centrale étudiée dans ce mémoire est la suivante : la politique sous-jacente à la transition à la télédiffusion numérique constitue-t-elle un défi en regard des préoccupations traditionnelles afférentes au rôle de la radiodiffusion dans la démocratie canadienne ? Adoptant une approche de économie politique institutionnelle, cette étude se fonde sur l'étude de documents gouvernementaux ou provenant des entreprises privées oeuvrant dans le secteur ainsi que sur des entretiens effectués avec certains acteurs clés de la radiodiffusion canadienne. Cette thèse offre une contribution unique au savoir quant à trois aspects : établir des paramètres clairs permettant de différencier les politiques de la réglementation dans le domaine de la radiodiffusion ; offrir la première étude détaillée sur la transition canadienne à la télévision numérique, et présenter une analyse du développement et de l'impact de l'autoréglementation et de la coréglementation dans les politiques canadiennes relatives à la radiodiffusion. Les conclusions de cette étude mettent en lumière les dynamiques de pouvoir existant entre les divers acteurs engagés dans le processus d'élaboration et d'adoption des politiques canadiennes, l'influence des nouvelles technologies et les grandes orientations politiques ayant prévalu dans le domaine de la radiodiffusion depuis l'adoption d
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Michaels, Alan Jason. "Digital chaotic communications." Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/34849.
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This dissertation provides the conceptual development, modeling and simulation, physical
implementation, and measured hardware results for a practicable digital coherent chaotic
communication system. Such systems are highly desirable for robust communications due to
the maximal entropy signal characteristics that satisfy Shannon's ideal noise-like waveform
and provide optimal data transmission across a flat communications channel. At the core of
the coherent chaotic communications system is a fully digital chaotic circuit, providing an
efficiently controllable mechanism that overcomes the traditional bottleneck of chaotic circuit
state synchronization. The analytical, simulation, and hardware results yield a generalization of direct sequence spread spectrum waveforms, that can be further extended to create a new class of maximal entropy waveforms suitable for optimized channel performance, maximal entropy transmission of chaotically spread amplitude modulated data constellations, and
permission-based multiple access systems.
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Arredondo, Alberto. "Downlink beamforming for mobile communications." Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3035934.
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Çiftçi, Mahmut. "Channel equalization for chaotic communications systems." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/15464.
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Cox, Criston W. "Optimizing bandwidth of tactical communications systems." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Jun%5FCox.pdf.
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Thesis (M.S. in Systems Technology (Joint Command, Control, Communications, Computers and Intelligence (JC4I))--Naval Postgraduate School, June 2005.Thesis Advisor(s): William Kemple, John Osmundson. Includes bibliographical references (p. 59-60). Also available online.
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Fasoulas, Aristides Ioannis. "Inmarsat communications system : a systems approach." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/28293.
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Fitch, Michael Robert. "Operational support systems for satellite communications." Thesis, Open University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413825.
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Aspland, Michael J. "Interoperable communications systems governance and risk." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Dec/09Dec%5FAspland.pdf.
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Thesis (M.A. in Security Studies (Homeland Security and Defense))--Naval Postgraduate School, December 2009.Thesis Advisor(s): Bergin, Richard. Second Reader: Munks, Jeffrey. "December 2009." Description based on title screen as viewed on January 27, 2010. Author(s) subject terms: Interoperable communications; multi-discipline, multi-jurisdictional radio communications; risk and governance; shared governance; policy and consensus teams, Monterey Police Department. Includes bibliographical references (p. 71-73). Also available in print.
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Chan, Christopher Wing Tai. "Magneto-inductive wave data communications systems." Thesis, University of Oxford, 2014. https://ora.ox.ac.uk/objects/uuid:014605c8-fc15-4166-a382-695042b05312.
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Metamaterials display unusual electromagnetic properties, such as, a negative effective permeability and negative effective permittivity. This has sparked much interest due to possibility of negative refraction which was later confirmed by experiments. The ability of magnetically coupled resonant circuits to display an effective permeability lead to the discovery of magneto-inductive waves. These waves are only supported on arrays of magnetically coupled resonant circuits. Research into magneto-inductive waves has been largely concentrated on their use in filters and their potential use in magnetic resonance imaging. However, some work has proposed the use of magneto-inductive waveguides as a data transfer medium. This report builds on previous work which found that an optimum existed for terminal-waveguide coupling, and aims to investigate the application of magneto-inductive waves in data transfer systems. A brief overview of the topic is given along with a description of the underlying characteristics. Factors that affect the capacity of magneto-inductive wave data transfer systems, such as inter element coupling, were identified. Two novel structures, both with the intent of increasing the bandwidth via different methods, are studied. One, by making a pseudo one-dimensional channel from a two-dimensional structure, and the other by using a dual-layer design to increase the coupling between adjacent elements. Both systems are modelled, using simple circuit theory and the impedance matrix method, and a comparison between simulated behaviour and experimental observation was made. There is discussion about the differences between experiment and simulation as well as their limitations. Magneto-inductive wave data transfer systems are eventually expected to support multiple terminals and as previous research only considered two-terminal systems, an investigation into the response of a one- and two-dimensional system with a blocking terminal was undertaken. The system was modelled, again using simple circuit theory and the impedance matrix method, and simulation and experiment were compared. As a whole, the simulations showed good agreement with experiments, after some initial adjustments. Both one- and two-dimensional systems showed that their performance was not severely effected by a blocking terminal. This suggests that magneto-inductive waveguides could support more terminals.
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Alizadeh, Ardalan. "Cognitive Communications for Emerging Wireless Systems." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1470226402.
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Nordberg, Jörgen. "Signal Enhancement in Wireless Communications Systems." Doctoral thesis, Ronneby : Blekinge Institute of Technology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-00229.
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Digital Wireless communications has been one of the fastest growing communication techniques during the last decade. Today there exists several different communication systems that use wireless techniques. They share one common property that they transmit data through a radio interface. The radio channel is a tough channel that will both distort and disturb the transmitted signal in various ways. In Jörgen Nordberg's PhD-thesis "Signal Enhancement in Wireless Communications Systems" several different signal enhancement schemes are presented. They have the objective to minimize the impact of the channel. The main part of this thesis presents work on interference cancellation, i.e. how to reduce the impact of other interfering signals on the channel of interest. This is achieved by utilizing the spatial domain, i.e. the receiver is using several antennas to receive the transmitted signals. By using a multitude of antennas techniques like spatial diversity, adaptive antenna arrays, signal separation and beamforming can be applied to combat the interfering signals. In the single antenna case there is often a need to do channel equalization. Since, channel equalization is an inverse filtering, it will often result in estimation of equalization filter parameters of very high order. To reduce the both the complexity and improve the convergence speed of the equalization filter parameter estimation subband processing techniques can be used. In this case the received signal is separated up into different frequency bands (subbands) and decimated according to the bandwidth of the signal. The channel equalization problem is then solved for each subband at a lower sampling rate. Hence, the channel equalization problem is transformed from estimating the parameters of a high order filter into estimating several filter of much lower order.Ett av områdena inom telekommunikation som har ökat mest de senaste åren är radio kommunikation. Det finns många olika varianter av trådlösa radio system, men de har alla en sak gemensamt, de överför information/data via ett radiogränssnitt. Signaler som sänds över en radiokanal kommer på grund av många olika anledningar att bli störda eller distorderade. I Jörgen Nordbergs doktorsavhandling ?Signal Enhancement in Wireless Communication Systems? presenteras flera metoder för att förbättra kvaliten i de mottagna signalerna vilket ger betydande kvalitetsförbättring. Huvuddelen av denna doktorsavhandling behandlar interferensundertrycking, d.v.s. hur man undertrycker oönskad störning på den egna radiokanalen. Dessa metoder är baserade på användning av flera antenner i mottagaren. Genom att ta emot signalerna med flera antenner så kan metoder såsom diversitetskombinering, adaptiva antenner, lobformning, signal separation användas för att förbättra kvaliteten i den mottagna signalen. Om mottagaren har en antenn så behövs oftast kanalutjämning för att förbättra den mottagna signalen och undertrycka intersymbolinterferens. Eftersom kanalutjämning är en typ av inversfiltrering leder detta ofta till estimering av filterparametrar av hög ordning. Estimeringsproblem av hög ordning leder ofta till komplexitetsproblem och konvergensproblem hos estimerings algoritmen. För att motverka dessa problem så presenteras i denna avhandling en kanalutjämnare som är baserad på subbandsteknik. I denna kanalutjämnare så delas den mottagna signalen upp i flera frekvensband (subband) som decimeras till en takt som motsvarar subbandets bandbredd varefter filterparametrarna estimeras i denna lägre takt. Därvid har estimeringsproblemet delats upp i flera små problem som kan hanteras enklare.
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Olson, Erica, and Ellinor Segerlind. "Villkorade lov eller startbesked enligt PBL 4 kap. 14 § 1 : planbestämmelsens förekomst och tillämpning i detaljplaner." Thesis, Högskolan Väst, Avdelningen för data-, elektro- och lantmäteriteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-11450.
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I arbetet för en hållbar utveckling är frågorna angående mark- och vattenområdens användning högst central. För att uppnå effektiv användning är det grundläggande att mark- och vattenområden används för de ändamål som de anses mest lämpade för. I vissa fall kan åtgärder behöva utföras för att ett område ska bli lämpligt för sitt ändamål. För att säkerställa att åtgärderna utförs, innan användningen av marken ändras, kan villkor om detta läggas in som planbestämmelse i detaljplan. Planbestämmelsen kallas villkor för lov eller startbesked. I denna studie behandlas villkor som är beroende av att en anläggning byggs ut. Paragrafen för detta återfinns i plan- och bygglagen (PBL) 4 kap. 14 § 1. Det huvudsakliga syftet med studien är att undersöka om och i så fall hur Sveriges kommuner använder sig av planbestämmelsen. För att komma fram till detta kartlägger studien vilka kommuner som använder sig av planbestämmelsen och i vilken utsträckning. Vidare studeras också i vilka sammanhang som planbestämmelsen används. Studien undersöker dessutom definitioner av begrepp i PBL, förarbeten och rättspraxis samt hur kommunerna tolkat några av begreppen. För att undersöka detta användes både en kvantitativ, kvalitativ och juridisk metod. I studien granskas samtliga 290 kommuners detaljplaner som vann laga kraft under år 2016. Resultatet av studien visar att bland totalt 1142 detaljplaner återfanns planbestämmelsen i 36 utav planerna. Användning av planbestämmelsen förekommer bland 25 kommuner med en geografisk spridning över nästan hela landet, med viss koncentration vid Sveriges landsgräns. I detaljplaner vid strand- samt fjällnära lägen syntes en frekvent användning av villkorade lov eller startbesked. I resultatet framkom även att planbestämmelser avseende anläggningar för avlopp finns högst representerade, därefter anläggningar för vatten följt av trafik. Användning av villkor avseende energi finns med i endast ett sammanhang. De begrepp som berörs i resultatet är komma till stånd och väsentlig ändring. Utredningar av definitioner för de olika begreppen i paragrafen visar att det i PBL, förarbeten eller rättspraxis inte finns tydliga definitioner. Resultatet visar att kommunernas tolkning av begreppet komma till stånd i de flesta fall överensstämmer med det som kan bedömas rimligt för att uppfylla syftet med planbestämmelsen.The questions about the use of land and water plays a central part in the work for a sustainable development. To achieve an efficient usage, it’s important that land and water is used for the purpose it’s most suited for. In some cases, different actions are necessary for an area to be suitable for its purpose. To ensure that actions are executed, before the usage of land changes, different conditions can be established as a plan regulation in detail development plans. The plan regulation is called conditions for permit or starting clearance. This study address the conditions dependent of a facility development. The paragraph can be found in the Planning and Building Act 4 Chap. 14 § 1. The main purpose of this study is to investigate if and in such case how the municipalities of Sweden use the plan regulation. To achieve this the study mapped which municipalities that use plan regulations and in what extent. It’s also investigated in what context the plan regulations are used. The study also examines definitions of terms stated in the Planning and Building Act, preparatory work or legal praxis and how the municipality interpret some of these terms. To investigate this fact both a quantitative, qualitative and legal method were used. The study covers all the detail development plans that went into legal force during 2016 among all the 290 municipalities in Sweden. The result of the study discovered that 36 out of 1142 detail development plans included plan regulations. The use of the plan regulation was discovered in 25 municipalities almost all over the country, with certain concentration at the border of Sweden. The study shows that plan regulations was frequently used in detail development plans close to waterfronts and alps. The result also shows that plan regulations were most represented in cases of sewerage facilities, followed by water supply facilities and traffic. The use of plan regulations when it comes to energy facilities was only represented in one case. The terms that is concerned in the result is carry out and significant changes. Investigations of the definitions of the different terms in the paragraph shows that there weren’t any clear definitions in either Planning and Building Act, preparatory work or legal praxis. Most of the cases shows that the municipality interpret the term carry out according with what is reasonable to fulfil the purpose of the plan regulation.
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Silva, Mário Marques da. "Emergent Radio Systems." Doctoral thesis, Instituto Superior Técnico, 2005. http://hdl.handle.net/11144/350.
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Emergent services are demanding higher data rates, especially in the downlink. Wideband Code Division Multiple Access (WCDMA) is the key to reach this development in cellular communications. To obtain this, it is important to find schemes able to reduce Inter-Path Interference (IPI) and Multiple Access Interference (MAI), and to explore new types of diversity. These are the objectives of the present thesis.
Interference cancellation subject considers post-processing and pre-processing schemes. A new linear Multi-User Detector (MUD) is proposed and analyzed. As pre-processing schemes, the new Pre-distortion and the Precoder schemes are studied and analyzed.
New types of diversity are also presented and analyzed. A new post-processing detector for the Vertical Bell Laboratories Layered Space-Time (V-BLAST) Multiple Input Multiple Output (MIMO) scheme, optimized for WCDMA signals subject to frequency selective fading, is proposed and analyzed. Moreover, a new frequency domain pre-processing scheme for frequency-selective fading MIMO channels is also proposed and analyzed.
The new Beam-Selective Transmit Diversity (BSTD) can be seen as a composite scheme where the MAI reduction is performed jointly with the exploration of transmit diversity, without additional Mobile Station (MS) complexity.
It is shown that, in most conditions, the pre-processing scheme for MIMO channels tends to achieve the best performance in most scenarios, being followed by the BSTD which allows interference cancellation and provides diversity. Both schemes tend to lead to good performances and capacities, facing the requirements of the emergent cellular communication systems. Depending on the complexity and size constraints imposed to the MS, the present thesis suggests the scheme that should be selected to allow such improvements
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Marzolini, Remo G. A. "Demodulator techniques in satellite communications systems for direct broadcast systems." n.p, 1995. http://ethos.bl.uk/.
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Xia, Bin, and 夏斌. "Enhanced techniques for broadband wireless communications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B29144231.
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Locquet, Alexandre Daniel. "Chaotic optical communications using delayed feedback systems." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/10431.
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Chaotic dynamics produced by optical delay systems have interesting applications in telecommunications. Optical chaos can be used to transmit secretly, in real-time, a message between an emitter and a receiver. The noise-like appearance of chaos is used to conceal the message, and the synchronization of the receiver with the chaotic emitter is used to decode the message. This work focuses on the study of two crucial topics in the field of chaotic optical communications.
The first topic is the synchronization of chaotic external-cavity laser diodes, which are among the most promising chaotic emitters for secure communications. It is shown that, for edge-emitting lasers, two drastically different synchronization regimes are possible. The regimes differ in terms of the delay time in the synchronization and in terms of the robustness of the synchronization with respect to parameter mismatches between the emitter and the receiver. In vertical-cavity surface-emitting lasers, the two linearly-polarized components of the electric field also exhibit isochronous and anticipating synchronization when the coupling between the lasers is isotropic. When the coupling is polarized, the linearly-polarized component that is parallel to the injected polarization tends to synchronize isochronously with the injected optical field, while the other component tends to be suppressed, but it can also be antisynchronized.
The second topic is the analysis of time series produced by optical chaotic emitters subjected to a delayed feedback. First, we verify with experimental data that chaos produced by optical delay systems is highly complex. This high complexity is demonstrated by estimating chaos dimension and entropy from experimental time series and from models of optical delay systems. Second, by analyzing chaotic time series, it is shown that the value of the delay of a single-delay system can always be identified, independently of the type of system used and of its complexity. Unfortunately, an eavesdropper can use this information on the delay value to break the cryptosystem. We propose a new cryptosystem with two delayed feedback loops that increases the difficulty of the delay identification problem.
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Houdeshell, Jack E. "Bandwidth optimization of underwater acoustic communications systems." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA391477.
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Thesis (M.S. in Engineering Acoustics) Naval Postgraduate School, March 2001.Thesis advisor(s): Smith, Kevin B. ; Nagle, Daniel T. "March 2001." Includes bibliographical references (p. 39-40). Also Available in print.
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Locquet, Alexandre Daniel. "Chaotic optical communications using delayed feedback systems." Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-01102006-133806/.
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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2006.Bertrand Boussert, Committee Member ; Douglas B. Williams, Committee Member ; William T. Rhodes, Committee Member ; Yves Berthelot, Committee Member ; David S. Citrin, Committee Chair.
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Dawson, Robert Edward. "Secure communications for critical infrastructure control systems." Queensland University of Technology, 2008. http://eprints.qut.edu.au/20710/.
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In March 2000, 1 million litres of raw sewage was released into the water system of Maroochy Shire on Queensland’s sunshine coast. This environmental disaster was caused by a disgruntled ex-contractor using a radio transmitter to illicitly access the electronically controlled pumps in the control system. In 2007 CNN screened video footage of an experimental attack against a electrical generator. The attack caused the generator to shake and smoke, visually showing the damage caused by cyber attack. These attacks highlight the importance of securing the control systems which our critical infrastructures depend on. This thesis addresses securing control systems, focusing on securing the communications for supervisory control and data acquisition (SCADA) systems. We review the architectures of SCADA systems and produce a list of the system constraints that relate to securing these systems. With these constraints in mind, we survey both the existing work in information and SCADA security, observing the need to investigate further the problem of secure communications for SCADA systems. We then present risk modelling techniques, and model the risk in a simple SCADA system, using the ISM, a software tool for modelling information security risk. In modelling the risk, we verify the hypothesis that securing the communications channel is an essential part of an effective security strategy for SCADA systems. After looking at risk modelling, and establishing the value of securing communications, we move on to key management for SCADA systems. Appropriate key management techniques are a crucial part of secure communications, and form an important part of the contributions made in this work. We present a key management protocol that has been designed to run under the constraints specific to SCADA systems. A reductionist security proof is developed for a simplified version of the protocol, showing it is secure in the Bellare Rogaway model.
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Yu, Xiaoming. "Multibeam smart antenna systems for wireless communications." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0034/NQ66298.pdf.
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Luo, Tuo. "Performance enhancements in practical MIMO communications systems /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?ECED%202007%20LUO.
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Weliwitegoda, Dhineth Chamara. "Equaliser performance optimisation for digital communications systems." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417191.
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Moss, Jonathan G. O. "Spread spectrum technologies for future communications systems." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285021.
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Jafar, Maysam. "Coherent systems for indoor optical wireless communications." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427622.
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Gorcin, Ali. "Multidimensional Signal Analysis for Wireless Communications Systems." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4680.
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Wireless communications systems underwent an evolution as the voice oriented applications evolved to data and multimedia based services. Furthermore, current wireless technologies, regulations and the un-
derstanding of the technology are insufficient for the requirements of future wireless systems. Along with the rapid rise at the number of users, increasing demand for more communications capacity to deploy multimedia applications entail effective utilization of communications resources. Therefore, there is a need for effective spectrum allocation, adaptive and complex modulation, error recovery, channel estimation, diversity and code design techniques to allow high data rates while maintaining desired quality of service, and reconfigurable and flexible air interface technologies for better interference and fading management. However, traditional communications system design is based on allocating fixed amounts of resources to the user and does not
consider adaptive spectrum utilization.
Technologies which will lead to adaptive, intelligent, and aware wireless communications systems are expected to come up with consistent methodologies to provide solutions for the capacity, interference, and
reliability problems of the wireless networks. Spectrum sensing feature of cognitive radio systems are a step forward to better recognize the problems and to achieve efficient spectrum allocation. On the other hand, even though spectrum sensing can constitute a solid base to achieve the reconfigurability and awareness goals of next generation networks, a new perspective is required to benefit from the whole dimensions of the available electro hyperspace. Therefore, spectrum sensing should evolve to a more general and comprehensive awareness providing a mechanism, not only as a part of CR systems which provide channel occupancy information but also as a communication environment awareness component of dynamic spectrum access paradigm which
can adapt sensing parameters autonomously to ensure robust identification and parameter estimation for the signals over the monitored spectrum. Such an approach will lead to recognition of communications opportunities in different dimensions of spectrum hyperspace, and provide necessary information about the air interfaces, access techniques and waveforms that are deployed over the monitored spectrum to accomplish adaptive resource management and spectrum access.
We define multidimensional signal analysis as a methodology, which not only provides the information that the spectrum hyperspace dimension in interest is occupied or not, but also reveals the underlaying information regarding to the parameters, such as employed channel access methods, duplexing techniques and other parameters related to the air interfaces of the signals accessing to the monitored channels and more. To achieve multidimensional signal analysis, a comprehensive sensing, classification, and a detection approach is required at the initial stage. In this thesis, we propose the multidimensional signal analysis procedures
under signal identification algorithms in time, frequency. Moreover, an angle of arrival estimation system for wireless signals, and a spectrum usage modeling and prediction method are proposed as multidimensional signal analysis functionalities.
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SANTOS, ALEXANDRE BESSA DOS. "POLARIZATION EFFECTS IN OPTICAL FIBER COMMUNICATIONS SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7013@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOOs efeitos que causam limitações nas comunicações ópticas referentes a polarização se resumem essencialmente na Dispersão dos Modos de Polarização (PMD), nas Perdas Dependentes da Polarização (PDL), e no Ganho Dependente da Polarização (PDG). Estes efeitos podem aparecer na transmissão de forma isolada ou combinada, gerando distorções no sinal. Primeiramente estes efeitos foram estudados individualmente, cada efeito sendo analisado e quantificado sob diversos aspectos. Através de uma analise teórica e experimental foi proposto uma nova técnica de medida de penalidade de potência envolvendo os efeitos estudados. Depois de um estudo detalhado sobre os efeitos isolados, analisou-se os efeitos combinados de PMD e PDL. Diversos emuladores de PMD, elementos com PDL variável e emuladores de PMD e PDL fizeram parte de um longo estudo sobre estes efeitos combinados. Procurou-se ressaltar a importância e os cuidados necessários que se deve tomar para a construção de um emulador de PMD. Na última etapa, foram estudados os efeitos de PMD e PDG oriundos de um sistema utilizando amplificação Raman. Desta forma foi possível evidenciar, caracterizar e relacionar os efeitos da polarização nas fibras ópticas.
The polarization effects that cause limitations in optical communications are essentially the Polarization Mode Dispersion (PMD), the Polarization Dependent Loss (PDL), and the Polarization Dependent Gain (PDG). These effects can appear either isolated or in combinations, generating signal distortion. These effects were first investigated individually under different experimental situations and then combined effects were studied. A new technique for measuring the power penalties corresponding to these effects was proposed. The combined effects of PMD and PDL in PMD emulators were evaluated and quantified. Thumb rules for the manufacture of PDL-free emulators were proposed. The effects of PMD and PDG originated from Raman amplification were also studied and compared with theoretical predictions.
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COSTA, RENATA BRAZ FALCAO DA. "CHANNEL ESTIMATION OVER POWER LINE COMMUNICATIONS SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=11480@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORA utilização das linhas de potência para fins de comunicação vem recebendo grande atenção nos últimos anos, principalmente devido a grande demanda por serviços de telecomunicações. A grande virtude é que as linhas de potência para comunicação apresentam uma solução sem a necessidade de nova fiação. Além disso, apresentam saída de potência disponível em todos os cômodos de uma residência, onde o terminal de comunicação possa ser usado, são de fácil instalação e acima de tudo apresentam custo reduzido. Sendo assim a comunicação através de linhas de potência vem se mostrando uma solução viável na oferta de serviços de telecomunicações. Esta tese investigou os sistemas PLC no que diz respeito à estimação do canal. Foi desenvolvido um método paramétrico de estimação do canal PLC baseado no algoritmo EM (Expectation Maximization). Foi feita a avaliação de desempenho combinando modulação OFDM (Orthogonal Frequency Division Multiplexing), estimação do canal PLC e equalização, sendo utilizado como referencias os equalizadores ZF (Zero Forcing) e MMSE (Minimum Mean Square Error).
The powerline communications systems have been receiving increasing attention in last few years. Power line communications presents a no new wires solution with the additional advantages of ubiquitous node availability, easy installation, and cost effectiveness. This thesis investigation the powerline estimation channel. It was presented parametric channel estimation method using EM (Expectation Maximization) algorithm. The performance using OFDM (Orthogonal Frequency Division Multiplexing), PLC Channel estimation and equalization was availability. The performance was studied using two equalization techniques Zero- Forcing and Minimum Mean Square Error.
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Sekioka, Yasuyuki. "Heuristic communications support systems for knowledge management." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10539.
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Mohapi, Setumo J. (Setumo James). "Power control for spread spectrum communications systems." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/39756.
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Kodikara, Patabandi C. K. "Multimedia communications over 3G wireless communication systems." Thesis, University of Surrey, 2004. http://epubs.surrey.ac.uk/844270/.
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This thesis addresses the transmission of video over third generation radio access networks. The first part of the thesis investigates the capabilities of Universal Terrestrial Radio Access Networks (UTRAN) in terms of the provision of multimedia communications. The error performance and traffic requirements of real-time video transmission over circuit switched and packet switched connections are examined. The effect of network parameter settings upon video performances is evaluated, and optimum radio bearer configurations for the transmission of video are derived. A method of estimating received video quality after transmission over error prone environments is developed. The quality estimation is based on a distortion model, which accurately models the overall distortion seen in decoder frame reconstruction. This includes quantisation distortion, concealment distortion, and error propagation. Based on the developed performance model, optimum MTU (Maximum Transfer Unit) size for efficient wireless video communications over a packet switched access network is derived. The second part of the thesis investigates quality enhancement techniques for multimedia traffic transmitted over wireless channels. Quality enhancement is achieved at three levels of the transmission process: link level, application level and system level. Link level quality enhancement techniques are designed to optimise the allocation of link level parameter values according to the media characteristics. A novel Unequal Error Protection scheme and a novel Unequal Power Allocation scheme are designed to exploit the inherent diversity in the subjective importance of different sections of compressed media. The algorithms are developed and analysed for transmission of video over 3G wireless systems. The effectiveness of these algorithms is demonstrated through the results of simulated transmission over a UMTS channel. Application level quality enhancement techniques are designed to explore the time-varying nature of the wireless channel. A number of link adaptation schemes are proposed for real time video communication and real-time video streaming over 3G wireless systems. These algorithms are designed to enhance the perceptual video quality, and the system utilisation. This is achieved by adapting the allocated radio network parameters and the source parameters, according to a feedback channel condition. Simulation results show a significant performance improvement compared to non-adaptive schemes. Finally, system level adaptation techniques are designed for efficient radio resource allocation in multi-user scenarios. Two adaptive resource allocation schemes are proposed and analysed for real-time video communications in a UMTS system. The proposed algorithms are shown to provide improved performances in terms of average received video quality and user satisfaction. Key words: Wireless Communication, Multimedia communication. Video Transmission.
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Tsukada, Manabu. "Communications Management in Cooperative Intelligent Transportation Systems." Paris, ENMP, 2011. http://www.theses.fr/2011ENMP0092.
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Les systèmes de transport intelligents (STI) coopératifs sont des systèmes ou les véhicules, l'infrastructure routière, les centres de contrôle de trafic et d'autres entités échangent des informations afin d'assurer une meilleure sécurité routière, l'efficacité du trafic et le confort des usagers de la route. C'est dans ce but que l'architecture de station STI a été spécifié par l'ISO et l'ETSI. Le concept de cette architecture de référence permet aux stations STI-véhicules et stations STI-infrastructures de s'organiser dans un réseau véhiculaire adhoc (VANET), tout en utilisant des protocoles de communication tels qu'GeoNetworking IP v6 et IEEE802. 11p ainsi que toute autre technologie d'accès afin de se connecter de manière transparente à internet. Plusieurs chemins peuvent donc être accessibles à une station STI véhicule pour communiquer avec d'autres stations STI. Les chemins sont de trois types: le chemin direct, le chemin optimisé, et le chemin d'ancré. L'objectif de cette étude est d'optimiser la communication entre stations STI en sélectionnant le meilleur chemin de communication disponible. . Cela exige d'abord de recueillir les informations disponibles localement dans la station STI (la position, la vitesse, les exigences des applications, les caractéristiques des supports de communication, les capacités , l'état du chemin), ainsi que les informations des stations STI voisines (position, vitesse, services, etc. . ). Ces informations sont ensuite traitées par le biais d'un algorithme de prise de décision. Premièrement, nous définissons un module réseau qui permet la combinaison d'IPv6 avec le Geo Networking. Deuxièmement, nous proposons un module de gestion inter-couche pour la sélection du meilleur chemin. Nos contributions s'intègrent dans l'architecture de station STI par la définition de la relation entre la couche réseau et transport (qui héberge la contribution Geonetworking IPv6) et l'entité verticale de gestion inter-couche (qui accueille l'algorythme de décision pour la sélection de chemin). Nous avons spécifié les fonctions permettant l'échange de paramétres par l'intermédiaire de la SAP (Service Acess Point) entre la couche réseau et l'entité de gestion (MN-SAP). Les paramètres utilisés dans l'entité de gestion inter-couche sont extraits d'une manière agnostique par rapport aux protocoles de la couche réseau et transport, ce qui permet de remplacer facilement les éléments d'une couche sans affecter les autres (par exemple, remplacer NEMO par une autre protocole de mobilité) et de permuter plusieurs piles réseau (on peut choisir d'utiliser la pile par une autre protocole de mobilité) et de permuter plusieurs piles réseau (on peut choisir d'utiliser la pile IPv6 ou bien la pile GeoNetworking, ou encore une combinaison des deux à la fois ou même une autre pileCooperative Intelligent transportation Systems (Cooperative ITS) are the systems where multiple entities share information and tasks to achieve the ITS objectives (i. E. Road safety, traffic efficiency and comfort). Today, ITS Station architecture is being specified in ISO and ETSI as a result of discussion and consensus of the researchers and developers in ITS domain. In the architecture, ITS Stations are essential entities, that are distributed in vehicles, roadside infrastructure, centers and mobiles, to achieve the ITS objectives. The vehicle and roadside ITS Stations organize Vehicular Ad-hoc Network (VANET) to adapt multi-hop and highly dynamic network topology. GeoNetworking is a great candidate for VANET because the geographic routing shows strength in dynamic topology. In addition to VANET, the ITS Station equips multiple wireless network interfaces and connects to networks with multiple paths, which is called multihoming. The objective of the study is to optimize the communication between ITS Stations by improved decision-making algorithm using inter-component information exchange in IP-based cooperative ITS. First, we develop IPv6 GeoNetworking to take the advantages of both IP and GeoNetworking. Seconds, we propose a cross-layer based path selection management by extending a Service Access Point (SAP) between the network layer and the management entity specified in the ITS Station Architecture. The extended SAP is designed as most abstracted as possible to adapt to the future development of the ITS Station architecture. The proposed system is designed and implemented as a prototype. The prototype implementation is evaluated in both ideal and realistic scenarios using up to four vehicles. The network performance measurement is processed, visualized and analyzed with web-based tools
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Sun, Min-Te. "Supporting communications in ad hoc network systems /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486462702466432.
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Soderi, S. (Simone). "Evaluation of industrial wireless communications systems’ security." Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526212463.
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Abstract The worldwide success of wireless communications was originally fueled by the possibility to replace existing cables with wireless solutions. This phenomenon imposed the development of security engineering as a multidisciplinary field. Although wireless solutions can reduce installation costs and allow introducing new services, the end–users expect it to have the same level of security as they would normally have with wired solutions. Secure communications is an important part of the overall security of industrial wireless communications systems (IWCS). The aim of this thesis is to develop new security engineering methodologies for IWCS. The author develops countermeasures against confidentiality and integrity attacks and carries out a security analysis covering the protocol, electromagnetic and physical layer. In the first part of the thesis, Host Identity Protocol (HIP) is utilized to secure communication in an intra–vehicular network. Simulations and measurement campaigns are also conducted to evaluate the impact of the overhead on security in a tunnel, considering line–of–sight (LOS) and non–LOS (NLOS) scenarios. Electromagnetic analysis (EMA) is an important step in the development of safety–related systems. Today, the increasing usage of smaller integrated circuit also increases the susceptibility to electromagnetic (EM) interference. From near–field (NF) to far–field (FF) transformation, a method for the evaluation of the emissions leakage is investigated. The virtual EM (VEM) interface of the device–under–test (DUT) is studied, and it is described how an adversary can exploit it for denial of service (DoS) attacks. An effective jamming attack model is studied, and the theoretical calculations are validated with experiment–based results. Finally, focusing attention on physical layer security, two algorithms are developed. Active radio frequency fingerprinting (RFF) implements the exchange of a public key during the setup of secure communication. Afterwards, utilizing a jamming receiver in conjunction with the spread spectrum (SS) watermarking technique, the watermark–based blind physical layer security (WBPLSec) protocol is presented. The analysis and results indicate how the WBPLSec seems to be a valuable technique for deploying physical layer security by creating a secure region around the receiverTiivistelmä Langattoman tietoliikenteen maailmanlaajuista suosiota kiihdytti alun perin mahdollisuus korvata tietoliikennejärjestelmissä käytetyt kaapelit langattomilla ratkaisuilla. Ilmiö lisäsi myös tarvetta kehittää alan turvatekniikkaa monialaisen tutkimuksen pohjalta. Vaikka langattomat ratkaisut merkitsevät pienempiä asennuskustannuksia ja tarjoavat mahdollisuuksia luoda uudenlaisia palveluja, järjestelmien loppukäyttäjät edellyttävät kuitenkin niiden turvallisuuden olevan vastaavalla tasolla kuin langallisissa verkoissa. Myös teollisuuden langattomien tietoliikennejärjestelmen turvallisuus riippuu pitkälti viestintäkanavien turvallisuudesta. Väitöksen tavoitteena on kehittää uusia menetelmiä, joilla teollisuuden langattomat tietoliikennejärjestelmät voitaisiin turvata. Väitöksessä kehitetään toimenpiteitä tietoliikennejärjestelmien luottamuksellisuuteen ja koskemattomuuteen kohdistuvia hyökkäyksiä vastaan ja toteutetaan turvallisuusarviointi, joka kattaa järjestelmän protokollakerroksen sekä sähkömagneettisen ja fyysisen kerroksen. Väitöksen ensimmäisessä osassa hyödynnetään HIP–protokollaa (Host Identity Protocol) liikennevälineen sisäisen tietoliikennejärjestelmän turvallisuuden varmistamisessa. Lisäksi siinä kuvataan simulaatiot ja mittaushankkeet, joiden tavoitteena on arvioida käytetyn protokollan turvallisuusvaikutuksia esteettömän (line–of–sight, LOS) ja esteellisen (non–line–of–sight, NLOS) näköyhteyden tapauksissa. Sähkömagneettinen analyysi on tärkeä vaihe turvajärjestelmien kehitysprosessissa. Järjestelmissä käytetään yhä enemmän pieniä integroituja piirejä, mikä voi myös altistaa ne sähkömagneettisille (electromagnetic, EM) häiriöille. Väitöksessä tutkitaan lähikenttä–kaukokenttä -muunnokseen perustuvan arviointimenetelmän avulla sähkömagneettisen vuotosäteilyn tasoa. Lisäksi perehdytään testattavan laitteen (device under test, DUT) virtuaaliseen EM–liitäntään ja kuvataan, miten vastaavaa liitäntää voidaan hyödyntää palvelunestohyökkäyksissä. Väitöksessä tutkitaan myös tehokasta häirintämallia ja validoidaan teoreettisten laskelmien tulokset kokeellisesti. Lopuksi väitöksessä keskitytään tietoliikennejärjestelmän fyysisen kerroksen turvallisuuteen ja kehitetään kaksi algoritmia. Aktiivisen radiotaajuisen tunnistusmenetelmän avulla voidaan vaihtaa julkisia avaimia turvallista tietoliikenneyhteyttä muodostettaessa. Lisäksi esitellään vesileimausmenetelmään perustuva fyysisen kerroksen salausmenetelmä, WBPLSec. WBPLSec luo vastaanottimen ympärille suoja–alueen, minkä ansiosta se vaikuttaa analyysin ja tutkimustulosten perusteella olevan tehokas menetelmä toteuttaa fyysisen kerroksen suojaus
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Aleem, Syed A. "Protocol engineering issues for open systems communications." Thesis, University of Ottawa (Canada), 1990. http://hdl.handle.net/10393/6011.
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In this thesis we present real design criteria and design building blocks in a highly procedural way starting from the specification to the implementation stage. A subset of a real protocol, namely ISDN Q.931 (CCIT3), written in informal English will be translated to a formal specification using Estelle as the formal description technique. A means of incorporating the design criteria into the formal description of the protocol is presented and illustrated with Q.931 as example. This thesis will also derive the services a protocol expects from the operating system. Those services will be summarized and standardized in order to limit variability in the design process of a protocol. The system interface which has been a major source of variation in protocol implementation, will reduce to a set of a few well defined standard system calls by assuming a proposed standard operating system interface. This interface standard appears to be sufficient to allow the automatic development of complete protocol software. (Abstract shortened by UMI.)
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Yun, Paul M. "Parallel Bus Implementations in Satellite Communications Systems." International Foundation for Telemetering, 1988. http://hdl.handle.net/10150/615247.
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International Telemetering Conference Proceedings / October 17-20, 1988 / Riviera Hotel, Las Vegas, NevadaAs the volume of linkages in the satellite communications systems increases, the parallel bus between the various processors of the satellite becomes a bottle neck to transfer the commands and data. The remedies to this problem are trivial in the ground stations; however, this problem imposes severe restrictions in parallel bus implementation of the satellite communications systems. The most severe restriction is the minimization of wire connections in the physical layer to minimize the weight, size and power consumption, and also to maximize the reliability. Another restriction is the flexibility in the link layer to adapt the different characteristics of the command and data messages. In this paper, the implementation to overcome the imposed restrictions in both physical and link layer of the parallel bus will be discussed.
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Steele, Robert Joshua. "Determining Communications Resource Feasibility in a Tactical Communications Network." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/32418.
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In this paper, we present solutions concerning communications resource allocation for tactical communication networking. Given a mission definition (which defines communication needs among participants) and participant capabilities (such as processing power and bandwidth), algorithms are presented to determine if the mission as presented is feasible.
The mathematical foundation of the problem is presented, and a â staticâ model to determine feasibility is shown. Further evolution of the algorithm into a â dynamicâ model and the reasons for the more demanding requirements are presented. Reasoning behind use of the Netflo algorithm in the dynamic model is also discussed.
The inclusion of the algorithm in a stand-alone program is discussed, including overall program structure, graphical user interface components and alternative output (such as the generation of high level network policy). Finally, future work in this area is discussed.Master of Science
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Ho, Joseph S. M. "Mobility management for personal communications networks." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/14882.
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Li, Wei. "Regulation of connexin43 and astrocytic gap junctional intercellular communication in the central nervous system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0026/NQ51647.pdf.
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La, Pan Matthew Jonathan. "Security Issues for Modern Communications Systems: Fundamental Electronic Warfare Tactics for 4G Systems and Beyond." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/51042.
Full textAbstract:
In the modern era of wireless communications, radios are becoming increasingly more cognitive. As the complexity and robustness of friendly communications increases, so do the abilities of adversarial jammers. The potential uses and threats of these jammers directly pertain to fourth generation (4G) communication standards, as well as future standards employing similar physical layer technologies.
This paper investigates a number of threats to the technologies utilized by 4G and future systems, as well as potential improvements to the security and robustness of these communications systems. The work undertaken highlights potential attacks at both the physical layer and the multiple access control (MAC) layer along with improvements to the technologies which they target.
This work presents a series of intelligent, targeted jamming attacks against the orthogonal frequency division multiplexing (OFDM) synchronization process to demonstrate some security flaws in existing 4G technology, as well as to highlight some of the potential tools of a cognitive electronic warfare attack device. Performance analysis of the OFDM synchronization process are demonstrated in the presence of the efficient attacks, where in many cases complete denial of service is induced.
A method for cross ambiguity function (CAF) based OFDM synchronization is presented as a security and mitigation tactic for 4G devices in the context of cognitive warfare scenarios. The method is shown to maintain comparable performance to other correlation based synchronization estimators while offering the benefit of a disguised preamble. Sync-amble randomization is also discussed as a combinatory strategy with CAF based OFDM synchronization to prevent cognitive jammers for tracking and targeting OFDM synchronization.
Finally, this work presents a method for dynamic spectrum access (DSA) enabled radio identification based solely on radio frequency (RF) observation. This method represents the framework for which both the cognitive jammer and anti-jam radio would perform cognitive sensing in order to utilize the intelligent physical layer attack and mitigation strategies previously discussed. The identification algorithm is shown to be theoretically effective in classifying and identifying two DSA radios with distinct operating policies.Ph. D.