Quasioptical Systems


Book Description

"The increasing commercial use of millimeter wavelengths for remote sensing, communications, and radar systems has driven the need for new low-cost, high performance systems, and with it, the need for quasioptical systems.Combining a general introduction to Gaussian beams and quasioptical propagation with practical applications, QUASIOPTICAL SYSTEMS provides a state-of-the-art treatment of the design of low-loss, broadband systems at microwave to submillimeter wavelegnths. the approach presented involved utilizing a beam with a Gaussian distribution of field strength perpendicular to its axis, which in turn propagates in a simple predictable fashion. Features include: A Convenient summary of Gaussian beam propagation formulas; Extensive coverage of present-day quasioptical components and their performance; In-depth coverage of dielectric material uses at millimeter and submillimeter wavelengths; An analysis of lenses and mirrors together with design techniques; and much more!This book will be of key interest to systems designers, antenna engineers, communications systems engineers, and researchers."




Quasioptical Systems


Book Description

The increasing commercial use of millimeter wavelengths for remote sensing, communications, and radar systems has driven the need for new low-cost, high performance systems, and with it, the need for quasioptical systems.Combining a general introduction to Gaussian beams and quasioptical propagation with practical applications, QUASIOPTICAL SYSTEMS provides a state-of-the-art treatment of the design of low-loss, broadband systems at microwave to submillimeter wavelegnths. the approach presented involved utilizing a beam with a Gaussian distribution of field strength perpendicular to its axis, which in turn propagates in a simple predictable fashion. Features include: A Convenient summary of Gaussian beam propagation formulas; Extensive coverage of present-day quasioptical components and their performance; In-depth coverage of dielectric material uses at millimeter and submillimeter wavelengths; An analysis of lenses and mirrors together with design techniques; and much more!This book will be of key interest to systems designers, antenna engineers, communications systems engineers, and researchers.




Quasi-Optical Control of Intense Microwave Transmission


Book Description

Between February 17 and 20, 2004, approximately fifty scientists from ten countries came together at the Institute of Applied Physics (IAP), Nizhny Novgorod, Russia to participate in a NATO sponsored Advanced Research Workshop whose appellation is re flected in the title of this volume, namely Quasi Optical Control of Intense Microwave Transmission. The fashionable label “quasi optical ” has come into use in recent decades to denote structures whose characteristic dimensions exceed (sometimes by large factors) the free space radiation wavelength. Such structures were and are developed to replace the traditional single eigenmode ones in situations when high frequenc ies (short wavelengths) are combined with high powers, a combination that could otherwise lead to RF breakdown and high Ohmic wall heating rates. Treatments of guided wave propagation in oversized structures is aimed at pr eserving the propagating field coherence and thus to provide efficient transmission of RF power to remote destinations such as antennas, microwave ovens, plasma chemical reactors, nuclear fusion machines, and the like.







Planar Active Antennas and Quasi-optical Power Combining Arrays Using FET's and Slots


Book Description

This report presents design concepts and experimental data of planar active antenna and quasi-optical power combining arrays with strong coupling to realize a compact and low-cost radar and communication system. The prototype circuits for this purpose were made in a layered configuration using microstrip lines and in a uniplanar structure using CPW's. As an active source, an FET was selected. As a unit cell of the power combining array, a single layered active antenna using microstrip lines and slots was fabricated. In the design, small signal S-parameters were used to determine the circuit configuration while a large signal analysis to the entire circuit involving the slot antenna input impedance was carried out. The circuit designed for 10 GHz was found to operate at 9.3 GHz and the other designed for 25 GHz at 24 GHz. In addition, the circuit with CPW's and slot designed for 10 GHz was found to operate at 8.6 GHz. Based on these successful results, linear power combining arrays were made. For the strong coupling, each oscillator output is connected by a single transmission line. Several 6-element microstrip arrays and a 4-element CPW array were fabricated. In the former, sharp main beams were obtained. To obtain a millimeter-wave operating frequency, the second harmonic spatial power combining array made with FET's were demonstrated around 40 GHz. To show a topology of a 2-dimensional array, a 16-element dual polarized array at 7.8 GEL was made. To obtain the maximum in-phase radiation signal, impedance matching, a phase of the radiation signal and a signal phase of each oscillator were taken into account ... Active antenna, Quasi-optical technique, Optical control, Spatial power combiner.




Microwave and Millimeter Wave Circuits and Systems


Book Description

Microwave and Millimeter Wave Circuits and Systems: Emerging Design, Technologies and Applications provides a wide spectrum of current trends in the design of microwave and millimeter circuits and systems. In addition, the book identifies the state-of-the art challenges in microwave and millimeter wave circuits systems design such as behavioral modeling of circuit components, software radio and digitally enhanced front-ends, new and promising technologies such as substrate-integrated-waveguide (SIW) and wearable electronic systems, and emerging applications such as tracking of moving targets using ultra-wideband radar, and new generation satellite navigation systems. Each chapter treats a selected problem and challenge within the field of Microwave and Millimeter wave circuits, and contains case studies and examples where appropriate. Key Features: Discusses modeling and design strategies for new appealing applications in the domain of microwave and millimeter wave circuits and systems Written by experts active in the Microwave and Millimeter Wave frequency range (industry and academia) Addresses modeling/design/applications both from the circuit as from the system perspective Covers the latest innovations in the respective fields Each chapter treats a selected problem and challenge within the field of Microwave and Millimeter wave circuits, and contains case studies and examples where appropriate This book serves as an excellent reference for engineers, researchers, research project managers and engineers working in R&D, professors, and post-graduates studying related courses. It will also be of interest to professionals working in product development and PhD students.




Diffraction and Scattering in Launchers of Quasi-Optical Mode Converters for Gyrotrons


Book Description

In this work different methods for the calculation of diffraction and scattering in launchers of quasi-optical mode converters for gyrotrons are compared, ranked and extended. The extension gives the opportunity to take a tapered average radius of the waveguide antenna into account. The comparison and the extension of the fast field calculation methods for component synthesis opens the possibility to reduce diffraction and stray radiation of reliable and powerful millimeter wave sources.




Detection of Light


Book Description

Comprehensive, accessible, and physically based description of the approaches currently used to detect light, from X-ray to mm-wave.




Millimetre-Wave Optics, Devices and Systems


Book Description

The millimetre-wavelength region of the electromagnetic spectrum is increasingly exploited for a wide range of commercial, industrial, and military applications. Conventionally, this region is considered as lying "above" microwaves and "below" the infrared. Hence, in practice, millimetre-wave scientists have tended to pick and mix useful techniques on an empirical basis from both these areas. Millimetre-Wave Optics, Devices and Systems describes the fundamental physics of the quasi-optical techniques, devices, and system design for instruments processing millimetre-wave signals. Relevant ideas from Gaussian beam mode theory and antenna and transmission line theory are brought together to show the underlying unity of optics and electronics. Aimed at advanced undergraduates and postgraduates as well as millimetre-wave, laser optics, antenna, and microwave engineers, this book will also be of interest to manufacturers of millimetre-wave and microwave equipment.




Detectors and Sources for THz and IR


Book Description

IR and THz technologies are widely used in security screening and surveillance, astronomy, spectroscopy, biomedicine, food and package inspection, detection of concealed weapons, vision through camouflage, etc. There are increasing demands for the fast transmission of large amounts of data. THz radiation penetrates dielectric materials like plastics, ceramics or cardboard allowing contact-free testing. Medical imaging technologies can provide guidance for surgeons in delimiting the margins of tumors, help clinicians to visualize diseased areas, etc. Keywords: THz and IR Detectors, THz and IR Sources, Superconducting Photon Detectors, Superconducting THz Detectors, Graphene-based Detectors, THz Sensors with Metamaterials, Photoconductive Antenna Detectors, Imaging, Communication, Spectroscopy, Sensing, Security Screening, Surveillance, Astronomy, Biomedicine, Food Inspection, Package Inspection, Concealed Weapons Detection, Transmission of Large Amounts of Data, Non-destructive Testing, Contact-free Testing, Medical Imaging Technologies.