Advances In Terahertz Technology And Its Applications

This book highlights the growing applications of THz technology and various modules used for their successful realization. The enormous advantages of THz devices like higher resolution, spatial directivity, high-speed communication, greater bandwidth, non-ionizing signal nature and compactness make them useful in various applications like communication, sensing, security, safety, spectroscopy, manufacturing, bio-medical, agriculture, imaging, etc. Since the THz radiation covers frequencies from 0.1THz to around 10THz and highly attenuated by atmospheric gases, they are used in short-distance applications only. The book focuses on recent advances and different research issues in terahertz technology and presents theoretical, methodological, well-established and validated empirical works dealing with the different topics.

The terahertz regime of the electromagnetic spectrum was largely unexplored due to the lack of technology needed to generate and detect the radiation. However, in the last couple of decades, there has been a dramatic increase in tools needed to harness the radiation. This remarkable progress made in the development of terahertz sources, components, and detectors has resulted in an ever-increasing inquisitiveness of the applications of terahertz technology in a wide range of fields including medicine, pharmaceuticals, security, sensing, and quality assurance. This book, Terahertz Spectroscopy - A Cutting Edge Technology, presents an overview of the recent advances in terahertz technology and their application in a vast array of fields. The scientists and students are encouraged to read and share the content of this volume. The book also provides a good starting point for researchers who are new to the terahertz regime. The various chapters of the book have been written by renowned scientists in different parts of the world who are at the forefront of terahertz research fields. It is our (InTech publisher, editor, and authors) hope that this book will enhance knowledge and stimulate more interest and future research in terahertz technology.

This book covers the latest advances in the techniques employed to manage the THz radiation and its potential uses. It has been subdivided in three sections: THz Detectors, THz Sources, Systems and Applications. These three sections will allow the reader to be introduced in a logical way to the physics problems of sensing and generation of the terahertz radiation, the implementation of these devices into systems including other components and finally the exploitation of the equipment for real applications in some different field. All of the sections and chapters can be individually addressed in order to deepen the understanding of a single topic without the need to read the whole book. The THz Detectors section will address the latest developments in detection devices based on three different physical principles: photodetection, thermal power detection, rectification. The THz Sources section will describe three completely different generation methods, operating in three separate scales: quantum cascade lasers, free electron lasers and non-linear optical generation. The Systems and Applications section will take care of introducing many of the aspects needed to move from a device to an equipment perspective: control of terahertz radiation, its use in imaging or in spectroscopy, potential uses in security, and will address also safety issues. The text book is at a level appropriate to graduate level courses up to researchers in the field who require a reference book covering all aspects of terahertz technology.

This book offers a comprehensive report on the technological aspects of Mobile Health (mHealth) and discusses the main challenges and future directions in the field. It is divided into eight parts: (1) preventive and curative medicine; (2) remote health monitoring; (3) interoperability; (4) framework, architecture, and software/hardware systems; (5) cloud applications; (6) radio technologies and applications; (7) communication networks and systems; and (8) security and privacy mechanisms. The first two parts cover sensor-based and bedside systems for remotely monitoring patients’ health condition, which aim at preventing the development of health problems and managing the prognosis of acute and chronic diseases. The related chapters discuss how new sensing and wireless technologies can offer accurate and cost-effective means for monitoring and evaluating behavior of individuals with dementia and psychiatric disorders, such as wandering behavior and sleep impairments. The following two parts focus on architectures and higher level systems, and on the challenges associated with their interoperability and scalability, two important aspects that stand in the way of the widespread deployment of mHealth systems. The remaining parts focus on telecommunication support systems for mHealth, including radio technologies, communication and cloud networks, and secure health-related applications and systems. All in all, the book offers a snapshot of the state-of-art in mHealth systems, and addresses the needs of a multidisciplinary audience, including engineers, computer scientists, healthcare providers, and medical professionals, working in both academia and the industry, as well as stakeholders at government agencies and non-profit organizations.

Terahertz (THz) technology is an active area of research, but only in recent years has the application of THz waves (T waves) in food and agricultural industries been explored. Terahertz Technology: Principles and Applications in the Agri-Food Industry describes the operating principles of THz technology and discusses applications and advantages of the THz regime of the electromagnetic spectrum for use in the agri-food industry. The agri-food industry is focusing on the development of non-destructive quality evaluation techniques that can provide accurate analysis quickly and are environmentally friendly. Among such techniques is THz technology that provides a novel noninvasive approach to quality assessment and safety assurance of agri-food products. The low energy of T waves is best suited for the analysis of sensitive biomaterials and does not cause photoionization. Therefore, THz imaging is complementary to X-ray imaging. Although accessing the THz spectrum is tedious by conventional devices, the combination of optics and electronics principles has opened a dimension of research in this field. This book provides an overview of THz spectroscopy and imaging, system components, types of THz systems, and applications and advantages of THz for applications in the agri-food industry. It describes the basic working mechanism, operating principle, operation modes, and system components of THz spectroscopy and imaging. Various advancements in THz technology related to agricultural and food applications are discussed that could serve as a guidebook for all those working and interested in non-destructive food assessment techniques. Key Features: Explores broader applications of the THz regime in the agri-food sector Describes system components, different forms of THz systems, and the working principle of T waves for spectroscopic and imaging techniques Provides insights on future research needs for industrial implementation of THz technology Complements the knowledge of other existing non-destructive spectroscopy and imaging techniques for food analysis Although books on biomedical applications of THz have been published, no book is available that deals with applications in the agri-food industry. Hence, Terahertz Technology is beneficial for undergraduate and graduate students and those food industry professionals involved in research related to non-destructive quality assessment and imaging techniques.

The Terahertz frequency range (0.1 – 10)THz has demonstrated to provide many opportunities in prominent research fields such as high-speed communications, biomedicine, sensing, and imaging. This spectral range, lying between electronics and photonics, has been historically known as “terahertz gap” because of the lack of experimental as well as fabrication technologies. However, many efforts are now being carried out worldwide in order improve technology working at this frequency range. This book represents a mechanism to highlight some of the work being done within this range of the electromagnetic spectrum. The topics covered include non-destructive testing, teraherz imaging and sensing, among others.

This book highlights recent advances and applications in terahertz (THz) technology, addressing advanced topics such as THz biomedical imaging, pattern recognition and tomographic reconstruction for THz biomedical imaging by machine learning and artificial intelligence, THz imaging radars for autonomous vehicle applications, and THz imaging systems for security and surveillance. It also discusses theoretical, experimental, established and validated empirical work on these topics.

Key advances in Semiconductor Terahertz (THz) Technology now promises important new applications enabling scientists and engineers to overcome the challenges of accessing the so-called "terahertz gap". This pioneering reference explains the fundamental methods and surveys innovative techniques in the generation, detection and processing of THz waves with solid-state devices, as well as illustrating their potential applications in security and telecommunications, among other fields. With contributions from leading experts, Semiconductor Terahertz Technology: Devices and Systems at Room Temperature Operation comprehensively and systematically covers semiconductor-based room temperature operating sources such as photomixers, THz antennas, radiation concepts and THz propagation as well as room-temperature operating THz detectors. The second part of the book focuses on applications such as the latest photonic and electronic THz systems as well as emerging THz technologies including: whispering gallery resonators, liquid crystals, metamaterials and graphene-based devices. This book will provide support for practicing researchers and professionals and will be an indispensable reference to graduate students in the field of THz technology. Key features: Includes crucial theoretical background sections to photomixers, photoconductive switches and electronic THz generation & detection. Provides an extensive overview of semiconductor-based THz sources and applications. Discusses vital technologies for affordable THz applications. Supports teaching and studying increasingly popular courses on semiconductor THz technology.

These proceedings comprise invited papers from highly experienced researchers in THz technology and security applications. THz detection of explosives represents one of the most appealing technologies to have recently emerged in dealing with terrorist attacks encountered by civil security and military forces throughout the world. Discussed are the most advanced technologies and developments, the various points of operational strength and weaknesses as well as are suggestions and predictions the best technological solutions to overcome current operational limits. The current status of various levels of cooling in THz detectors, sources and associated electronics are also addressed. The goal was to provide a clear view on the current technologies available and the required advances needed in order to achieve more efficient systems. This goal was outlined in part by establishing the baseline of current uncertainty estimations in physics-based modelling and the identification of key areas which require additional research and development.

Terahertz waves, which lie in the frequency range of 0.1-10 THz, have long been investigated in a few limited fields, such as astronomy, because of a lack of devices for their generation and detection. Several technical breakthroughs made over the last couple of decades now allow us to radiate and detect terahertz waves more easily, which has trigg