10 research outputs found

    Multifunction Radios and Interference Suppression for Enhanced Reliability and Security of Wireless Systems

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    Wireless connectivity, with its relative ease of over-the-air information sharing, is a key technological enabler that facilitates many of the essential applications, such as satellite navigation, cellular communication, and media broadcasting, that are nowadays taken for granted. However, that relative ease of over-the-air communications has significant drawbacks too. On one hand, the broadcast nature of wireless communications means that one receiver can receive the superposition of multiple transmitted signals. But on the other hand, it means that multiple receivers can receive the same transmitted signal. The former leads to congestion and concerns about reliability because of the limited nature of the electromagnetic spectrum and the vulnerability to interference. The latter means that wirelessly transmitted information is inherently insecure. This thesis aims to provide insights and means for improving physical layer reliability and security of wireless communications by, in a sense, combining the two aspects above through simultaneous and same frequency transmit and receive operation. This is so as to ultimately increase the safety of environments where wireless devices function or where malicious wirelessly operated devices (e.g., remote-controlled drones) potentially raise safety concerns. Specifically, two closely related research directions are pursued. Firstly, taking advantage of in-band full-duplex (IBFD) radio technology to benefit the reliability and security of wireless communications in the form of multifunction IBFD radios. Secondly, extending the self-interference cancellation (SIC) capabilities of IBFD radios to multiradio platforms to take advantage of these same concepts on a wider scale. Within the first research direction, a theoretical analysis framework is developed and then used to comprehensively study the benefits and drawbacks of simultaneously combining signals detection and jamming on the same frequency within a single platform. Also, a practical prototype capable of such operation is implemented and its performance analyzed based on actual measurements. The theoretical and experimental analysis altogether give a concrete understanding of the quantitative benefits of simultaneous same-frequency operations over carrying out the operations in an alternating manner. Simultaneously detecting and jamming signals specifically is shown to somewhat increase the effective range of a smart jammer compared to intermittent detection and jamming, increasing its reliability. Within the second research direction, two interference mitigation methods are proposed that extend the SIC capabilities from single platform IBFD radios to those not physically connected. Such separation brings additional challenges in modeling the interference compared to the SIC problem, which the proposed methods address. These methods then allow multiple radios to intentionally generate and use interference for controlling access to the electromagnetic spectrum. Practical measurement results demonstrate that this effectively allows the use of cooperative jamming to prevent unauthorized nodes from processing any signals of interest, while authorized nodes can use interference mitigation to still access the same signals. This in turn provides security at the physical layer of wireless communications

    An ad hoc wireless mobile communications model for Special Operations Forces

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    The digitization of the battlefield enables special operators to use improved communications supported by computer networks across a range of missions. The communications paradigm is evolving toward mobile wireless ad hoc networks. This development enables an autonomous system of mobile nodes supporting peer-to-peer communications in forward-deployed military networks. Ad hoc networks have to establish a reliable, secure, instant, and usually temporary, communication infrastructure and to be able to access in a global communications infrastructure. Our model describes a global communication network supporting the special operator in mobile wireless communications. The main purpose is to provide a handheld wireless communications node which is capable of transferring voice, data, and imagery to and from parallel and vertical command structures within an environment replete with electronic countermeasures. The model will support the representation of requirements such as throughput, quality of service with low power consumption, and low probability of detection/interception. Special Forces are moving toward using commercial-off-the- shelf products and services based on availability and cost effectiveness. Using GloMoSim tool, we run simulations for a direct action scenario and compared the efficiency of on-demand and table-driven routing protocols under different bandwidths and communications loadshttp://www.archive.org/details/adhocwirelessmob00ogutFirst Lieutenant, Turkish ArmyApproved for public release; distribution is unlimited

    PHYSICAL LAYER SECURITY OF LARGE ANTENNA ARRAYS OPERATING IN THE NEAR-FIELD. NEAR-FIELD BEAMFOCUSING AND THE STUDY OF IT’S PHYSICAL LAYER SECURITY CAPABILITIES

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    This thesis explores the security aspects of near-field communications in the context of the upcoming 6th Generation wireless technology. With each decade witnessing significant advancements in cellular wireless communications, the demand for faster, more accessible, and secure networks continues to grow. Tra- ditional security approaches relying on higher-layer cryptography techniques may not be sufficient for the future massively connected world. Therefore, this research focuses on leveraging physical layer security techniques, specifically in the near-field regime, to enhance the confidentiality and privacy of wireless communications. The study begins with an examination of the state of the art, encompassing previous telecommunication generations, Multiple-Input Multiple-Output sys- tems, Multiple-Input Multiple-Output with Extremely Large Antenna Arrays, and an overview of physical layer security concepts. Subsequently, a compre- hensive analysis of the near-field channel modeling components is presented, exploring the unique propagation characteristics of electromagnetic waves within this region. The thesis then delves into the exploration of physical layer security at the near- field, employing the established channel model to calculate the secrecy rate in the downlink and achievable capacity in the uplink. Various scenarios involv- ing a malicious user in the communication link are considered, highlighting the inherent security capabilities of near-field communications. In conclusion, this research contributes to the advancement of secure com- munication technologies by providing insights into the physical layer security aspects of near-field communications in the context of 6th Generation. The findings show the potential of utilizing the propagation features of large an- tenna arrays such as the limited-depth beamforming to enhance security and privacy. The practical implications and potential applications of the research outcomes are also discussed.Esta tese explora os aspetos de segurança das comunicações de campo próximo no contexto da próxima tecnologia sem fios 6G. A cada década, testemunha- mos avanços significativos nas comunicações sem fio, a demanda por redes mais rápidas, acessíveis e seguras continua a crescer. Abordagens tradicionais de segurança que dependem de técnicas criptográficas em camadas superiores podem não ser suficientes para o futuro mundo altamente conectado. Portanto, esta pesquisa concentra-se nas técnicas de seguraça a nivél físico, especifica- mente no regime de campo próximo, para melhorar a confidencialidade e privacidade das comunicações sem fio. O estudo começa com uma análise do estado da arte, abrangendo gerações ante- riores de telecomunicações, sistemas Multiple Input Multiple Output (MIMO), MIMO com Extremely Large Antenna Arrays (ELAA)s, e uma visão geral dos conceitos de seguraça a nivél físico. Posteriormente, é apresentada uma análise abrangente dos componentes de modelagem do canal no campo próximo, explorando as características únicas de propagação de ondas eletromagnéticas nesta região. A tese, em seguida, aprofunda a exploração de seguraça a nivél físico no campo próximo, empregando o modelo de canal estabelecido para calcular a "Secrecy Rate"no "Downlink"e a capacidade máxima atingivel no "Uplink". Vários cenários envolvendo um utilizador malicioso na ligação de comunica- ção são considerados, destacando as capacidades inerentes de segurança das comunicações no campo próximo. Em conclusão, esta pesquisa contribui para o avanço das tecnologias de co- municação segura, fornecendo informações sobre os aspetos de segurança da camada física das comunicações no campo próximo no contexto de 6G. Os resultados mostram o potencial de utilizar as características de propagação de grandes matrizes de antenas, como o feixe de profundidade limitada, para melhorar a segurança e a privacidade. As implicações práticas e potenciais aplicações dos resultados da pesquisa também são discutidas

    Wireless sensor networks

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    Wireless sensor networks promise an unprecedented fine-grained interface between the virtual and the physical world. They are one of the most rapidly developing new information technologies, with applications in a wide range of fields including industrial process control, security and surveillance, environmental sensing, and structural health monitoring. The subject of this project is motivated by the urgent need to provide a comprehensive and organized survey of the field. It shows how the core challenges of energy efficiency, robustness, and autonomy are addressed in these systems by networking techniques across multiple layers. The topics covered include network deployment, wireless characteristics, time synchronization, congestion and error control, medium access, standards, topology control, routing, security, data transfer, transport protocols and new technologies and materials in fabricating sensors

    5G Outlook – Innovations and Applications

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    5G Outlook - Innovations and Applications is a collection of the recent research and development in the area of the Fifth Generation Mobile Technology (5G), the future of wireless communications. Plenty of novel ideas and knowledge of the 5G are presented in this book as well as divers applications from health science to business modeling. The authors of different chapters contributed from various countries and organizations. The chapters have also been presented at the 5th IEEE 5G Summit held in Aalborg on July 1, 2016. The book starts with a comprehensive introduction on 5G and its need and requirement. Then millimeter waves as a promising spectrum to 5G technology is discussed. The book continues with the novel and inspiring ideas for the future wireless communication usage and network. Further, some technical issues in signal processing and network design for 5G are presented. Finally, the book ends up with different applications of 5G in distinct areas. Topics widely covered in this book are: • 5G technology from past to present to the future• Millimeter- waves and their characteristics• Signal processing and network design issues for 5G• Applications, business modeling and several novel ideas for the future of 5

    5G Outlook – Innovations and Applications

    Get PDF
    5G Outlook - Innovations and Applications is a collection of the recent research and development in the area of the Fifth Generation Mobile Technology (5G), the future of wireless communications. Plenty of novel ideas and knowledge of the 5G are presented in this book as well as divers applications from health science to business modeling. The authors of different chapters contributed from various countries and organizations. The chapters have also been presented at the 5th IEEE 5G Summit held in Aalborg on July 1, 2016. The book starts with a comprehensive introduction on 5G and its need and requirement. Then millimeter waves as a promising spectrum to 5G technology is discussed. The book continues with the novel and inspiring ideas for the future wireless communication usage and network. Further, some technical issues in signal processing and network design for 5G are presented. Finally, the book ends up with different applications of 5G in distinct areas. Topics widely covered in this book are: • 5G technology from past to present to the future• Millimeter- waves and their characteristics• Signal processing and network design issues for 5G• Applications, business modeling and several novel ideas for the future of 5

    Mobile Ad-Hoc Networks

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    Being infrastructure-less and without central administration control, wireless ad-hoc networking is playing a more and more important role in extending the coverage of traditional wireless infrastructure (cellular networks, wireless LAN, etc). This book includes state-of the-art techniques and solutions for wireless ad-hoc networks. It focuses on the following topics in ad-hoc networks: vehicular ad-hoc networks, security and caching, TCP in ad-hoc networks and emerging applications. It is targeted to provide network engineers and researchers with design guidelines for large scale wireless ad hoc networks

    Abstracts on Radio Direction Finding (1899 - 1995)

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    The files on this record represent the various databases that originally composed the CD-ROM issue of "Abstracts on Radio Direction Finding" database, which is now part of the Dudley Knox Library's Abstracts and Selected Full Text Documents on Radio Direction Finding (1899 - 1995) Collection. (See Calhoun record https://calhoun.nps.edu/handle/10945/57364 for further information on this collection and the bibliography). Due to issues of technological obsolescence preventing current and future audiences from accessing the bibliography, DKL exported and converted into the three files on this record the various databases contained in the CD-ROM. The contents of these files are: 1) RDFA_CompleteBibliography_xls.zip [RDFA_CompleteBibliography.xls: Metadata for the complete bibliography, in Excel 97-2003 Workbook format; RDFA_Glossary.xls: Glossary of terms, in Excel 97-2003 Workbookformat; RDFA_Biographies.xls: Biographies of leading figures, in Excel 97-2003 Workbook format]; 2) RDFA_CompleteBibliography_csv.zip [RDFA_CompleteBibliography.TXT: Metadata for the complete bibliography, in CSV format; RDFA_Glossary.TXT: Glossary of terms, in CSV format; RDFA_Biographies.TXT: Biographies of leading figures, in CSV format]; 3) RDFA_CompleteBibliography.pdf: A human readable display of the bibliographic data, as a means of double-checking any possible deviations due to conversion

    Aeronautical Engineering - A special bibliography with indexes /supplement 1/

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    Annotated reference bibliography on aeronautical engineering document
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