Author: Ahmet Tekin
Publisher: CRC Press
ISBN: 1482207125
Category : Computers
Languages : en
Pages : 149
Book Description
High Frequency Communication and Sensing: Traveling-Wave Techniques introduces novel traveling wave circuit techniques to boost the performance of high-speed circuits in standard low-cost production technologies, like complementary metal oxide semiconductor (CMOS). A valuable resource for experienced analog/radio frequency (RF) circuit designers as well as undergraduate-level microelectronics researchers, this book: Explains the basics of high-speed signaling, such as transmission lines, distributed signaling, impedance matching, and other common practical RF background material Promotes a dual-loop coupled traveling wave oscillator topology, the trigger mode distributed wave oscillator, as a high-frequency multiphase signal source Introduces a force-based starter mechanism for dual-loop, even-symmetry, multiphase traveling wave oscillators, presenting a single-loop version as a force mode distributed wave antenna (FMDWA) Describes higher-frequency, passive inductive, and quarter-wave-length-based pumped distributed wave oscillators (PDWOs) Examines phased-array transceiver architectures and front-end circuits in detail, along with distributed oscillator topologies Devotes a chapter to THz sensing, illustrating a unique method of traveling wave frequency multiplication and power combining Discusses various data converter topologies, such as digital-to-analog converters (DACs), analog-to-digital converters (ADCs), and GHz-bandwidth sigma-delta modulators Covers critical circuits including phase rotators and interpolators, phase shifters, phase-locked loops (PLLs), delay-locked loops (DLLs), and more It is a significantly challenging task to generate and distribute high-speed clocks. Multiphase low-speed clocks with sharp transition are proposed to be a better option to accommodate the desired timing resolution. High Frequency Communication and Sensing: Traveling-Wave Techniques provides new horizons in the quest for greater speed and performance.
High Frequency Communication and Sensing
Author: Ahmet Tekin
Publisher: CRC Press
ISBN: 1482207125
Category : Computers
Languages : en
Pages : 149
Book Description
High Frequency Communication and Sensing: Traveling-Wave Techniques introduces novel traveling wave circuit techniques to boost the performance of high-speed circuits in standard low-cost production technologies, like complementary metal oxide semiconductor (CMOS). A valuable resource for experienced analog/radio frequency (RF) circuit designers as well as undergraduate-level microelectronics researchers, this book: Explains the basics of high-speed signaling, such as transmission lines, distributed signaling, impedance matching, and other common practical RF background material Promotes a dual-loop coupled traveling wave oscillator topology, the trigger mode distributed wave oscillator, as a high-frequency multiphase signal source Introduces a force-based starter mechanism for dual-loop, even-symmetry, multiphase traveling wave oscillators, presenting a single-loop version as a force mode distributed wave antenna (FMDWA) Describes higher-frequency, passive inductive, and quarter-wave-length-based pumped distributed wave oscillators (PDWOs) Examines phased-array transceiver architectures and front-end circuits in detail, along with distributed oscillator topologies Devotes a chapter to THz sensing, illustrating a unique method of traveling wave frequency multiplication and power combining Discusses various data converter topologies, such as digital-to-analog converters (DACs), analog-to-digital converters (ADCs), and GHz-bandwidth sigma-delta modulators Covers critical circuits including phase rotators and interpolators, phase shifters, phase-locked loops (PLLs), delay-locked loops (DLLs), and more It is a significantly challenging task to generate and distribute high-speed clocks. Multiphase low-speed clocks with sharp transition are proposed to be a better option to accommodate the desired timing resolution. High Frequency Communication and Sensing: Traveling-Wave Techniques provides new horizons in the quest for greater speed and performance.
Publisher: CRC Press
ISBN: 1482207125
Category : Computers
Languages : en
Pages : 149
Book Description
High Frequency Communication and Sensing: Traveling-Wave Techniques introduces novel traveling wave circuit techniques to boost the performance of high-speed circuits in standard low-cost production technologies, like complementary metal oxide semiconductor (CMOS). A valuable resource for experienced analog/radio frequency (RF) circuit designers as well as undergraduate-level microelectronics researchers, this book: Explains the basics of high-speed signaling, such as transmission lines, distributed signaling, impedance matching, and other common practical RF background material Promotes a dual-loop coupled traveling wave oscillator topology, the trigger mode distributed wave oscillator, as a high-frequency multiphase signal source Introduces a force-based starter mechanism for dual-loop, even-symmetry, multiphase traveling wave oscillators, presenting a single-loop version as a force mode distributed wave antenna (FMDWA) Describes higher-frequency, passive inductive, and quarter-wave-length-based pumped distributed wave oscillators (PDWOs) Examines phased-array transceiver architectures and front-end circuits in detail, along with distributed oscillator topologies Devotes a chapter to THz sensing, illustrating a unique method of traveling wave frequency multiplication and power combining Discusses various data converter topologies, such as digital-to-analog converters (DACs), analog-to-digital converters (ADCs), and GHz-bandwidth sigma-delta modulators Covers critical circuits including phase rotators and interpolators, phase shifters, phase-locked loops (PLLs), delay-locked loops (DLLs), and more It is a significantly challenging task to generate and distribute high-speed clocks. Multiphase low-speed clocks with sharp transition are proposed to be a better option to accommodate the desired timing resolution. High Frequency Communication and Sensing: Traveling-Wave Techniques provides new horizons in the quest for greater speed and performance.
Modern HF Signal Detection and Direction Finding
Author: Jay R. Sklar
Publisher: MIT Press
ISBN: 0262038293
Category : Computers
Languages : en
Pages : 369
Book Description
Detailed descriptions of detection, direction-finding, and signal-estimation methods, using consistent formalisms and notation, emphasizing HF antenna array sensing applications. Adaptive antenna array technology encompasses many powerful interference suppression approaches that exploit spatial differences among signals reaching a radio receiver system. Today, worldwide propagation phenomenology occurring in the High Frequency (HF) radio regime has made such interference common. In this book, Jay Sklar, a longtime researcher at MIT Lincoln Laboratory, presents detailed descriptions of detection, direction-finding, and signal-estimation methods applicable at HF, using consistent formalisms and notation. Modern electronic system technology has made many of these techniques affordable and practical; the goal of the book is to offer practicing engineers a comprehensive and self-contained reference that will encourage more widespread application of these approaches. The book is based on the author's thirty years of managing MIT Lincoln Laboratory work on the application of adaptive antenna array technologies to the sensing of HF communication signals. After an overview of HF propagation phenomenology, communication signal formats, and HF receiver architectural approaches, Sklar describes the HF propagation environment in more detail; introduces important modulation approaches and signaling protocols used at HF; discusses HF receiver system architectural features; and addresses signal processor architecture and its implementation. He then presents the technical foundation for the book: the vector model for a signal received at an adaptive array antenna. He follows this with discussions of actual signal processing techniques for detection and direction finding, including specific direction-finding algorithms; geolocation techniques; and signal estimation.
Publisher: MIT Press
ISBN: 0262038293
Category : Computers
Languages : en
Pages : 369
Book Description
Detailed descriptions of detection, direction-finding, and signal-estimation methods, using consistent formalisms and notation, emphasizing HF antenna array sensing applications. Adaptive antenna array technology encompasses many powerful interference suppression approaches that exploit spatial differences among signals reaching a radio receiver system. Today, worldwide propagation phenomenology occurring in the High Frequency (HF) radio regime has made such interference common. In this book, Jay Sklar, a longtime researcher at MIT Lincoln Laboratory, presents detailed descriptions of detection, direction-finding, and signal-estimation methods applicable at HF, using consistent formalisms and notation. Modern electronic system technology has made many of these techniques affordable and practical; the goal of the book is to offer practicing engineers a comprehensive and self-contained reference that will encourage more widespread application of these approaches. The book is based on the author's thirty years of managing MIT Lincoln Laboratory work on the application of adaptive antenna array technologies to the sensing of HF communication signals. After an overview of HF propagation phenomenology, communication signal formats, and HF receiver architectural approaches, Sklar describes the HF propagation environment in more detail; introduces important modulation approaches and signaling protocols used at HF; discusses HF receiver system architectural features; and addresses signal processor architecture and its implementation. He then presents the technical foundation for the book: the vector model for a signal received at an adaptive array antenna. He follows this with discussions of actual signal processing techniques for detection and direction finding, including specific direction-finding algorithms; geolocation techniques; and signal estimation.
Joint Communications and Sensing
Author: Kai Wu
Publisher: John Wiley & Sons
ISBN: 1119982936
Category : Technology & Engineering
Languages : en
Pages : 327
Book Description
JOINT COMMUNICATIONS AND SENSING Authoritative resource systematically introducing JCAS technologies and providing valuable information and knowledge to researchers and engineers Based on over six years of dedicated research on joint communications and sensing (JCAS) by the authors, their collaborators, and students, Joint Communications and Sensing is the first book to comprehensively cover the subject of JCAS, which is expected to deliver huge cost and energy savings, and therefore has become a hallmark of future 6G and next generation radar technologies. The book has three parts. Part I presents the basic JCAS concepts and applications and the basic signal processing algorithms to support JCAS. Part II covers communications-centric JCAS designs that describe how sensing can be integrated into communications networks such as 5G and 6G. Part III presents ways to integrate communications in various radar sensing technologies and platforms. Specific sample topics covered in Joint Communications and Sensing include: Three categories of JCAS systems, potential sensing applications of JCAS, signal processing fundamentals, and channel models for communications and radar Frameworks for perceptive mobile networks (PMNs), system modifications to enable PMN sensing, and PMN system issues Orthogonal time-frequency space waveform-based JCAS for IoT, including signal models, echo pre-processing, and target parameter estimation Joint Communications and Sensing provides valuable information and knowledge to researchers and engineers in the communications and radar sensing communities and industries, enabling them to upskill and prepare for JCAS technology research and development. The text is of particular interest to engineers in the wireless communications industry who are pursuing new capabilities in 6G.
Publisher: John Wiley & Sons
ISBN: 1119982936
Category : Technology & Engineering
Languages : en
Pages : 327
Book Description
JOINT COMMUNICATIONS AND SENSING Authoritative resource systematically introducing JCAS technologies and providing valuable information and knowledge to researchers and engineers Based on over six years of dedicated research on joint communications and sensing (JCAS) by the authors, their collaborators, and students, Joint Communications and Sensing is the first book to comprehensively cover the subject of JCAS, which is expected to deliver huge cost and energy savings, and therefore has become a hallmark of future 6G and next generation radar technologies. The book has three parts. Part I presents the basic JCAS concepts and applications and the basic signal processing algorithms to support JCAS. Part II covers communications-centric JCAS designs that describe how sensing can be integrated into communications networks such as 5G and 6G. Part III presents ways to integrate communications in various radar sensing technologies and platforms. Specific sample topics covered in Joint Communications and Sensing include: Three categories of JCAS systems, potential sensing applications of JCAS, signal processing fundamentals, and channel models for communications and radar Frameworks for perceptive mobile networks (PMNs), system modifications to enable PMN sensing, and PMN system issues Orthogonal time-frequency space waveform-based JCAS for IoT, including signal models, echo pre-processing, and target parameter estimation Joint Communications and Sensing provides valuable information and knowledge to researchers and engineers in the communications and radar sensing communities and industries, enabling them to upskill and prepare for JCAS technology research and development. The text is of particular interest to engineers in the wireless communications industry who are pursuing new capabilities in 6G.
A Strategy for Active Remote Sensing Amid Increased Demand for Radio Spectrum
Author: National Academies of Sciences, Engineering, and Medicine
Publisher: National Academies Press
ISBN: 0309373085
Category : Science
Languages : en
Pages : 254
Book Description
Active remote sensing is the principal tool used to study and to predict short- and long-term changes in the environment of Earth - the atmosphere, the oceans and the land surfaces - as well as the near space environment of Earth. All of these measurements are essential to understanding terrestrial weather, climate change, space weather hazards, and threats from asteroids. Active remote sensing measurements are of inestimable benefit to society, as we pursue the development of a technological civilization that is economically viable, and seek to maintain the quality of our life. A Strategy for Active Remote Sensing Amid Increased Demand for Spectrum describes the threats, both current and future, to the effective use of the electromagnetic spectrum required for active remote sensing. This report offers specific recommendations for protecting and making effective use of the spectrum required for active remote sensing.
Publisher: National Academies Press
ISBN: 0309373085
Category : Science
Languages : en
Pages : 254
Book Description
Active remote sensing is the principal tool used to study and to predict short- and long-term changes in the environment of Earth - the atmosphere, the oceans and the land surfaces - as well as the near space environment of Earth. All of these measurements are essential to understanding terrestrial weather, climate change, space weather hazards, and threats from asteroids. Active remote sensing measurements are of inestimable benefit to society, as we pursue the development of a technological civilization that is economically viable, and seek to maintain the quality of our life. A Strategy for Active Remote Sensing Amid Increased Demand for Spectrum describes the threats, both current and future, to the effective use of the electromagnetic spectrum required for active remote sensing. This report offers specific recommendations for protecting and making effective use of the spectrum required for active remote sensing.
Phased Arrays for Radio Astronomy, Remote Sensing, and Satellite Communications
Author: Karl F. Warnick
Publisher: Cambridge University Press
ISBN: 1108423922
Category : Mathematics
Languages : en
Pages : 471
Book Description
Discover a modern approach to the analysis, modeling and design of high sensitivity phased arrays. Network theory, numerical methods and computational electromagnetic simulation techniques are uniquely combined to enable full system analysis and design optimization. Beamforming and array signal processing theory are integrated into the treatment from the start. Digital signal processing methods such as polyphase filtering and RFI mitigation are described, along with technologies for real-time hardware implementation. Key concepts from interferometric imaging used in radio telescopes are also considered. A basic development of theory and modeling techniques is accompanied by problem sets that guide readers in developing modeling codes that retain the simplicity of the classical array factor method while incorporating mutual coupling effects and interactions between elements. Combining current research trends with pedagogical material suitable for a first-year graduate course, this is an invaluable resource for students, teachers, researchers, and practicing RF/microwave and antenna design engineers.
Publisher: Cambridge University Press
ISBN: 1108423922
Category : Mathematics
Languages : en
Pages : 471
Book Description
Discover a modern approach to the analysis, modeling and design of high sensitivity phased arrays. Network theory, numerical methods and computational electromagnetic simulation techniques are uniquely combined to enable full system analysis and design optimization. Beamforming and array signal processing theory are integrated into the treatment from the start. Digital signal processing methods such as polyphase filtering and RFI mitigation are described, along with technologies for real-time hardware implementation. Key concepts from interferometric imaging used in radio telescopes are also considered. A basic development of theory and modeling techniques is accompanied by problem sets that guide readers in developing modeling codes that retain the simplicity of the classical array factor method while incorporating mutual coupling effects and interactions between elements. Combining current research trends with pedagogical material suitable for a first-year graduate course, this is an invaluable resource for students, teachers, researchers, and practicing RF/microwave and antenna design engineers.
Handbook of Terahertz Technology for Imaging, Sensing and Communications
Author: D Saeedkia
Publisher: Elsevier
ISBN: 0857096494
Category : Technology & Engineering
Languages : en
Pages : 684
Book Description
The recent development of easy-to-use sources and detectors of terahertz radiation has enabled growth in applications of terahertz (Thz) imaging and sensing. This vastly adaptable technology offers great potential across a wide range of areas, and the Handbook of terahertz technology for imaging, sensing and communications explores the fundamental principles, important developments and key applications emerging in this exciting field.Part one provides an authoritative introduction to the fundamentals of terahertz technology for imaging, sensing and communications. The generation, detection and emission of waves are discussed alongside fundamental aspects of surface plasmon polaritons, terahertz near-field imaging and sensing, room temperature terahertz detectors and terahertz wireless communications. Part two goes on to discuss recent progress and such novel techniques in terahertz technology as terahertz bio-sensing, array imagers, and resonant field enhancement of terahertz waves. Fiber-coupled time-domain spectroscopy systems (THz-TDS), terahertz photomixer systems, terahertz nanotechnology, frequency metrology and semiconductor material development for terahertz applications are all reviewed. Finally, applications of terahertz technology are explored in part three, including applications in tomographic imaging and material spectroscopy, art conservation, and the aerospace, wood products, semiconductor and pharmaceutical industries.With its distinguished editor and international team of expert contributors, the Handbook of terahertz technology for imaging, sensing and communications is an authoritative guide to the field for laser engineers, manufacturers of sensing devices and imaging equipment, security companies, the military, professionals working in process monitoring, and academics interested in this field. - Examines techniques for the generation and detection of terahertz waves - Discusses material development for terahertz applications - Explores applications in tomographic imaging, art conservation and the pharmaceutical and aerospace industries
Publisher: Elsevier
ISBN: 0857096494
Category : Technology & Engineering
Languages : en
Pages : 684
Book Description
The recent development of easy-to-use sources and detectors of terahertz radiation has enabled growth in applications of terahertz (Thz) imaging and sensing. This vastly adaptable technology offers great potential across a wide range of areas, and the Handbook of terahertz technology for imaging, sensing and communications explores the fundamental principles, important developments and key applications emerging in this exciting field.Part one provides an authoritative introduction to the fundamentals of terahertz technology for imaging, sensing and communications. The generation, detection and emission of waves are discussed alongside fundamental aspects of surface plasmon polaritons, terahertz near-field imaging and sensing, room temperature terahertz detectors and terahertz wireless communications. Part two goes on to discuss recent progress and such novel techniques in terahertz technology as terahertz bio-sensing, array imagers, and resonant field enhancement of terahertz waves. Fiber-coupled time-domain spectroscopy systems (THz-TDS), terahertz photomixer systems, terahertz nanotechnology, frequency metrology and semiconductor material development for terahertz applications are all reviewed. Finally, applications of terahertz technology are explored in part three, including applications in tomographic imaging and material spectroscopy, art conservation, and the aerospace, wood products, semiconductor and pharmaceutical industries.With its distinguished editor and international team of expert contributors, the Handbook of terahertz technology for imaging, sensing and communications is an authoritative guide to the field for laser engineers, manufacturers of sensing devices and imaging equipment, security companies, the military, professionals working in process monitoring, and academics interested in this field. - Examines techniques for the generation and detection of terahertz waves - Discusses material development for terahertz applications - Explores applications in tomographic imaging, art conservation and the pharmaceutical and aerospace industries
Third-generation and Wideband HF Radio Communications
Author: Eric E. Johnson
Publisher: Artech House
ISBN: 1608075036
Category : Technology & Engineering
Languages : en
Pages : 262
Book Description
Wideband HF. Book jacket.
Publisher: Artech House
ISBN: 1608075036
Category : Technology & Engineering
Languages : en
Pages : 262
Book Description
Wideband HF. Book jacket.
Radio Engineering for Wireless Communication and Sensor Applications
Author: Antti V. Räisänen
Publisher: Artech House
ISBN: 9781580536691
Category : Technology & Engineering
Languages : en
Pages : 424
Book Description
Covering a wide range of application areas, from wireless communications and navigation, to sensors and radar, this practical resource offers you the first comprehensive, multidisciplinary overview of radio engineering. You learn important techniques to help you with the generation, control, detection and utilization of radio waves, and find detailed guidance in radio link, amplifier, and antenna design. The book approaches relevant problems from both electromagnetic theory based on MaxwellOCOs equations and circuit theory based on KirchoffOCOs and OhmOCOs laws, including brief introductions to each theory."
Publisher: Artech House
ISBN: 9781580536691
Category : Technology & Engineering
Languages : en
Pages : 424
Book Description
Covering a wide range of application areas, from wireless communications and navigation, to sensors and radar, this practical resource offers you the first comprehensive, multidisciplinary overview of radio engineering. You learn important techniques to help you with the generation, control, detection and utilization of radio waves, and find detailed guidance in radio link, amplifier, and antenna design. The book approaches relevant problems from both electromagnetic theory based on MaxwellOCOs equations and circuit theory based on KirchoffOCOs and OhmOCOs laws, including brief introductions to each theory."
Antenna and Sensor Technologies in Modern Medical Applications
Author: Yahya Rahmat-Samii
Publisher: John Wiley & Sons
ISBN: 1119683300
Category : Technology & Engineering
Languages : en
Pages : 624
Book Description
A guide to the theory and recent development in the medical use of antenna technology Antenna and Sensor Technologies in Modern Medical Applications offers a comprehensive review of the theoretical background, design, and the latest developments in the application of antenna technology. Written by two experts in the field, the book presents the most recent research in the burgeoning field of wireless medical telemetry and sensing that covers both wearable and implantable antenna and sensor technologies. The authors review the integrated devices that include various types of sensors wired within a wearable garment that can be paired with external devices. The text covers important developments in sensor-integrated clothing that are synonymous with athletic apparel with built-in electronics. Information on implantable devices is also covered. The book explores technologies that utilize both inductive coupling and far field propagation. These include minimally invasive microwave ablation antennas, wireless targeted drug delivery, and much more. This important book: Covers recent developments in wireless medical telemetry Reviews the theory and design of in vitro/in vivo testing Explores emerging technologies in 2D and 3D printing of antenna/sensor fabrication Includes a chapter with an annotated list of the most comprehensive and important references in the field Written for students of engineering and antenna and sensor engineers, Antenna and Sensor Technologies in Modern Medical Applications is an essential guide to understanding human body interaction with antennas and sensors.
Publisher: John Wiley & Sons
ISBN: 1119683300
Category : Technology & Engineering
Languages : en
Pages : 624
Book Description
A guide to the theory and recent development in the medical use of antenna technology Antenna and Sensor Technologies in Modern Medical Applications offers a comprehensive review of the theoretical background, design, and the latest developments in the application of antenna technology. Written by two experts in the field, the book presents the most recent research in the burgeoning field of wireless medical telemetry and sensing that covers both wearable and implantable antenna and sensor technologies. The authors review the integrated devices that include various types of sensors wired within a wearable garment that can be paired with external devices. The text covers important developments in sensor-integrated clothing that are synonymous with athletic apparel with built-in electronics. Information on implantable devices is also covered. The book explores technologies that utilize both inductive coupling and far field propagation. These include minimally invasive microwave ablation antennas, wireless targeted drug delivery, and much more. This important book: Covers recent developments in wireless medical telemetry Reviews the theory and design of in vitro/in vivo testing Explores emerging technologies in 2D and 3D printing of antenna/sensor fabrication Includes a chapter with an annotated list of the most comprehensive and important references in the field Written for students of engineering and antenna and sensor engineers, Antenna and Sensor Technologies in Modern Medical Applications is an essential guide to understanding human body interaction with antennas and sensors.
Ship Sensors
Author: R. Glenn Wright
Publisher: Taylor & Francis
ISBN: 1003855245
Category : Transportation
Languages : en
Pages : 267
Book Description
When combined with artificial intelligence, advanced computing architectures and enhanced communications, sensor technologies can monitor vessel performance and the adjacent environment to detect conditions that may hinder voyage completion. This book provides insight into the present and future of sensor architectures and configurations that can enhance vessel performance and further improve the safety of navigation. It covers topics such as traditional and expanded sensor functions in engineering and navigation, as well as new sensor capabilities that can provide greater insight into vessel behavior and performance and enhance awareness of passenger, crew and other human activities. Chapters offer background information on typical legacy vessel sensor configurations and current International Maritime Organization (IMO) requirements for onboard sensors and future regulatory trends before discussing modern sensors and current- generation “smart” sensors that provide enhanced situational awareness to watchstanders. A vision of next- generation sensors currently being investigated for shipboard use is provided along with long- term trends in quantum sensing and computing that promise radical change across a wide variety of vessel functions. Insight is also given into cybersecurity factors so essential to all sensor systems. Ship Sensors: Conventional, Unmanned and Autonomous is ideal for professional seafarers, maritime academics and university students, and developers of maritime sensors and systems.
Publisher: Taylor & Francis
ISBN: 1003855245
Category : Transportation
Languages : en
Pages : 267
Book Description
When combined with artificial intelligence, advanced computing architectures and enhanced communications, sensor technologies can monitor vessel performance and the adjacent environment to detect conditions that may hinder voyage completion. This book provides insight into the present and future of sensor architectures and configurations that can enhance vessel performance and further improve the safety of navigation. It covers topics such as traditional and expanded sensor functions in engineering and navigation, as well as new sensor capabilities that can provide greater insight into vessel behavior and performance and enhance awareness of passenger, crew and other human activities. Chapters offer background information on typical legacy vessel sensor configurations and current International Maritime Organization (IMO) requirements for onboard sensors and future regulatory trends before discussing modern sensors and current- generation “smart” sensors that provide enhanced situational awareness to watchstanders. A vision of next- generation sensors currently being investigated for shipboard use is provided along with long- term trends in quantum sensing and computing that promise radical change across a wide variety of vessel functions. Insight is also given into cybersecurity factors so essential to all sensor systems. Ship Sensors: Conventional, Unmanned and Autonomous is ideal for professional seafarers, maritime academics and university students, and developers of maritime sensors and systems.