Through-the-Wall Radar Imaging


Book Description

Through-the-wall radar imaging (TWRI) allows police, fire and rescue personnel, first responders, and defense forces to detect, identify, classify, and track the whereabouts of humans and moving objects. Electromagnetic waves are considered the most effective at achieving this objective, yet advances in this multi-faceted and multi-disciplinary technology require taking phenomenological issues into consideration and must be based on a solid understanding of the intricacies of EM wave interactions with interior and exterior objects and structures. Providing a broad overview of the myriad factors involved, namely size, weight, mobility, acquisition time, aperture distribution, power, bandwidth, standoff distance, and, most importantly, reliable performance and delivery of accurate information, Through-the-Wall Radar Imaging examines this technology from the algorithmic, modeling, experimentation, and system design perspectives. It begins with coverage of the electromagnetic properties of walls and building materials, and discusses techniques in the design of antenna elements and array configurations, beamforming concepts and issues, and the use of antenna array with collocated and distributed apertures. Detailed chapters discuss several suitable waveforms inverse scattering approaches and revolve around the relevance of physical-based model approaches in TWRI along with theoretical and experimental research in 3D building tomography using microwave remote sensing, high-frequency asymptotic modeling methods, synthetic aperture radar (SAR) techniques, impulse radars, airborne radar imaging of multi-floor buildings strategies for target detection, and detection of concealed targets. The book concludes with a discussion of how the Doppler principle can be used to measure motion at a very fine level of detail. The book provides a deep understanding of the challenges of TWRI, stressing its multidisciplinary and phenomenological nature. The breadth and depth of topics covered presents a highly detailed treatment of this potentially life-saving technology.




Vulnerability of Wireline and Cellular Telecommunications Networks to High Power Radio Frequency Fields


Book Description

High level magnetic fields can upset and damage electronics, as well as disrupt or disable computer software. Thus, high power radio frequency (RF) fields pose a threat to electronics and software dependent systems. Critical infrastructures such as telecomm. could be targeted. This report examines the general vulnerability of public and emergency telecomm. networks to high power RF fields. The following primary questions are addressed: (1) Can the loss of a node (e.g., a switching station or a wireless base station), or nodes, cascade through the telecomm. network, causing a large-scale system blackout or crash?; (2) Can a high power RF device disrupt or disable a node? What vulnerable equipment is located a various nodal types? Charts and tables.







An Analysis of Regulatory Frameworks for Wireless Communications, Societal Concerns and Risk


Book Description

This thesis analyses how and why culture and geography influence the allocation and licensing of the radio frequency (RF) spectrum in different nations. Based on a broad comparative study of 235 countries, an inter-disciplinary approach is used to explore regulatory frameworks and attitudes toward risk. In addition, detailed case studies of the UK, France, the US and Ecuador provide deeper insights into the main contrasting regulatory styles. Three alternative sociological theories are used to analyse and explain the results for both the in-depth and broad brush studies. The Cultural Theory of Mary Douglas and co-workers is first used to categorise countries in terms of perceptual filters. The empirical findings indicate some countries to be apparently exceptional in their behaviour. The theory of Bounded Rationality is used to investigate and explain these apparent irrationalities. Finally, Rational Field Theory shows how beliefs and values guide administrations in their RF regulation. A number of key factors are found to dominate and patterns emerge. The European RF harmonisation is unique. Following European unification, wireless regulation is divided into two major camps (the EU and the US), which differ in their risk concerns, approach to top-down mandated standards, allocation of RF spectrum to licence-exempt bands and type approval process. The adoption of 3G cellular (UMTS versus CDMA2000) and digital TV standards (DVB-T/ATSC/ISDB-T) around the world reflects geopolitical and colonial influence. The language of a country is a significant indicator of its analogue TV standard (SECAM/PAL/NTSC). Interestingly, the longitude of a country to a fair extent defines RF allocation: Africa and West Asia follow Europe, whereas the Americas approximate the US. RF regulation and risk tolerability differ between tropical and non-tropical climates. The collectivised/centralised versus the individualised/market-based rationalities result in different regulatory frameworks and contrasting societal and risk concerns. The success of the top-down European GSM and the bottom-up Wi-Fi standards reveal how the central-planning and market-based approaches have thrived. Attitudes to RF human hazards and spurious emissions levels reveal that the US, Canada and Japan are more tolerant of these radiation risks than Europe. Australia, Canada, New Zealand, UK and USA encourage technological innovation. A practical benefit of this study is that it will give regulators more freedom to choose a rational RF licensing protocol, by better understanding the possibly self-imposed boundaries of cultural and geographical factors which are currently shaping allocation. Academically, there is utility in undertaking a cultural and geographic analysis of a topic that is mostly the domain of engineering, economic and legal analysts.




Computer Engineering in Applied Electromagnetism


Book Description

Computer Engineering in Applied Electromagnetism contains papers which were presented at the International Symposium on Electromagnetic Fields in Electrical Engineering, held in Maribor, Slovenia, 18-20 September 2003. It consists of three parts, Computational Techniques, Electromagnetic Engineering, and Special Applications. The contributions selected for the book cover a wide spectrum of theory and practice, being simultaneously of high theoretical level and deeply rooted in engineering problems. Thus, this volume touches on what is of key importance in electromagnetism.




The Evolution of Untethered Communications


Book Description

In response to a request from the Defense Advanced Research Projects Agency, the committee studied a range of issues to help identify what strategies the Department of Defense might follow to meet its need for flexible, rapidly deployable communications systems. Taking into account the military's particular requirements for security, interoperability, and other capabilities as well as the extent to which commercial technology development can be expected to support these and related needs, the book recommends systems and component research as well as organizational changes to help the DOD field state-of-the-art, cost-effective untethered communications systems. In addition to advising DARPA on where its investment in information technology for mobile wireless communications systems can have the greatest impact, the book explores the evolution of wireless technology, the often fruitful synergy between commercial and military research and development efforts, and the technical challenges still to be overcome in making the dream of "anytime, anywhere" communications a reality.




Radio Frequency and Microwave Effects on Biological Tissues


Book Description

Focussing on engineering aspects of RF/Microwave interaction with biological tissues This book discusses the advancement in bio-electromagnetics pertaining to this important issue of electromagentic field-bio interaction vis-a-vis the emission of electromagnetic radiations from mobile phones and their biological fallout. Divided into six chapters, it discusses basic issues in Electromagnetic Field-Biointeraction, dosimetery, instrumentation, and methods of measurement of specific absorption rate, criteria and magnitude of safe exposure and measurements of field in an open (unobstructed) environment.




Fundamentals of Wireless Communication


Book Description

This textbook takes a unified view of the fundamentals of wireless communication and explains cutting-edge concepts in a simple and intuitive way. An abundant supply of exercises make it ideal for graduate courses in electrical and computer engineering and it will also be of great interest to practising engineers.




Security in Computing and Communications


Book Description

This book constitutes the refereed proceedings of the 6th International Symposium on Security in Computing and Communications, SSCC 2018, held in Bangalore, India, in September 2018. The 34 revised full papers and 12 revised short papers presented were carefully reviewed and selected from 94 submissions. The papers cover wide research fields including cryptography, database and storage security, human and societal aspects of security and privacy.