Download or read book Design of Multi channel Radio frequency Front end for 200mhz Parallel Magnetic Resonance Imaging written by Xiaoqun Liu and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The increasing demands for improving magnetic resonance imaging (MRI) quality, especially reducing the imaging time have been driving the channel number of parallel magnetic resonance imaging (Parallel MRI) to increase. When the channel number increases to 64 or even 128, the traditional method of stacking the same number of radio-frequency (RF) receivers with very low level of integration becomes expensive and cumbersome. However, the cost, size, power consumption of the Parallel MRI receivers can be dramatically reduced by designing a whole receiver front-end even multiple receiver front-ends on a single chip using CMOS technology, and multiplexing the output signal of each receiver front-end into one channel so that as much hardware resource can be shared by as many channels as possible, especially the digitizer. The main object of this research is focused on the analysis and design of fully integrated multi-channel RF receiver and multiplexing technology. First, different architectures of RF receiver and different multiplexing method are analyzed. After comparing the advantages and the disadvantages of these architectures, an architecture of receiver front-end which is most suitable for fully on-chip multi-channel design is proposed and a multiplexing method is selected. According to this proposed architecture, a four-channel receiver front-end was designed and fabricated using TSMC 0.18Bm technology on a single chip and methods of testing in the MRI system using parallel planar coil array and phase coil array respectively as target coils were presented. Each channel of the receiver front-end includes an ultra low noise amplifier (LNA), a quadrature image rejection down-converter, a buffer, and a low-pass filter (LPF) which also acts as a variable gain amplifier (VGA). The quadrature image rejection downconverter consists of a quadrature generator, a passive mixer with a transimpedance amplifier which converts the output current signal of the passive mixer into voltage signal while acts as a LPF, and a polyphase filter after the TIA. The receiver has an over NF of 0.935dB, variable gain from about 80dB to 90dB, power consumption of 30.8mW, and chip area of 6mm2. Next, a prototype of 4-channel RF receiver with Time Domain Multiplexing (TDM) on a single printed circuit board (PCB) was designed and bench-tested. Then Parallel MRI experiment was carried out and images were acquired using this prototype. The testing results verify the proposed concepts.
Download or read book Development of Multi channel Radio Frequency Technology for Sodium and Potassium Magnetic Resonance Imaging at 7 0 Tesla Design and Clinical Application written by Daniel Wenz and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Automatic Design Tool for Robust Radio Frequency Decoupling Matrices in Magnetic Resonance Imaging written by Zohaib Mahmood and published by . This book was released on 2015 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis we study the design of robust decoupling matrices for coupled transmit radio frequency arrays used in magnetic resonance imaging (MRI). In a coupled parallel transmit array, because of the coupling itself, the power delivered to a channel is typically partially re-distributed to other channels. This power must then be dissipated in circulators resulting into a significant reduction in the power efficiency of the overall system. In this thesis, we propose an automated approach to design a robust decoupling matrix interfaced between the RF amplifiers and the coils. The decoupling matrix is optimized to ensure all forward power is delivered to the load. The decoupling condition dictates that the admittance matrix seen by power amplifiers with 50 Ohms output impedance is a diagonal matrix with matching 1 (or 0.02 Siemens) at the diagonal. Our tool computes the values of the decoupling matrix via a non linear optimization and generate a physical realization using reactive elements such as inductors and capacitors. The methods presented in this thesis scale to any arbitrary number of channels and can be readily applied to other coupled systems such as antenna arrays. Furthermore our tool computes parameterized dynamical models and performs sensitivity analysis with respect to patient head-size and head-position for MRI coils.
Download or read book Ultra High Field Magnetic Resonance Imaging written by Pierre-Marie Robitaille and published by Springer Science & Business Media. This book was released on 2007-12-31 with total page 487 pages. Available in PDF, EPUB and Kindle. Book excerpt: The foundation for understanding the function and dynamics of biological systems is not only knowledge of their structure, but the new methodologies and applications used to determine that structure. This volume in Biological Magnetic Resonance emphasizes the methods that involve Ultra High Field Magnetic Resonance Imaging. It will interest researchers working in the field of imaging.
Download or read book Microwave and RF Design written by Michael Bernard Steer and published by SciTech Publishing. This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Microwave & RF Design: A Systems Approach, 2nd Edition is a comprehensive treatment of the subject for advanced undergrad and graduate students (as well as professionals), focusing on the systems and emphasizing design. Components are covered in depth, but always with the idea of how they fit into modern radio, radar, and sensor systems. Advanced components and design techniques are presented along with a thoroughly modern treatment of traditional microwave theory and techniques."--pub. desc.
Download or read book RF Coils for MRI written by J. Thomas Vaughan and published by John Wiley & Sons. This book was released on 2012-12-19 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: The content of this volume has been added to eMagRes (formerly Encyclopedia of Magnetic Resonance) - the ultimate online resource for NMR and MRI. To date there is no single reference aimed at teaching the art of applications guided coil design for use in MRI. This RF Coils for MRI handbook is intended to become this reference. Heretofore, much of the know-how of RF coil design is bottled up in various industry and academic laboratories around the world. Some of this information on coil technologies and applications techniques has been disseminated through the literature, while more of this knowledge has been withheld for competitive or proprietary advantage. Of the published works, the record of technology development is often incomplete and misleading, accurate referencing and attribution assignment being tantamount to admission of patent infringement in the commercial arena. Accordingly, the literature on RF coil design is fragmented and confusing. There are no texts and few courses offered to teach this material. Mastery of the art and science of RF coil design is perhaps best achieved through the learning that comes with a long career in the field at multiple places of employment...until now. RF Coils for MRI combines the lifetime understanding and expertise of many of the senior designers in the field into a single, practical training manual. It informs the engineer on part numbers and sources of component materials, equipment, engineering services and consulting to enable anyone with electronics bench experience to build, test and interface a coil. The handbook teaches the MR system user how to safely and successfully implement the coil for its intended application. The comprehensive articles also include information required by the scientist or physician to predict respective experiment or clinical performance of a coil for a variety of common applications. It is expected that RF Coils for MRI becomes an important resource for engineers, technicians, scientists, and physicians wanting to safely and successfully buy or build and use MR coils in the clinic or laboratory. Similarly, this guidebook provides teaching material for students, fellows and residents wanting to better understand the theory and operation of RF coils. Many of the articles have been written by the pioneers and developers of coils, arrays and probes, so this is all first hand information! The handbook serves as an expository guide for hands-on radiologists, radiographers, physicians, engineers, medical physicists, technologists, and for anyone with interests in building or selecting and using RF coils to achieve best clinical or experimental results. About EMR Handbooks / eMagRes Handbooks The Encyclopedia of Magnetic Resonance (up to 2012) and eMagRes (from 2013 onward) publish a wide range of online articles on all aspects of magnetic resonance in physics, chemistry, biology and medicine. The existence of this large number of articles, written by experts in various fields, is enabling the publication of a series of EMR Handbooks / eMagRes Handbooks on specific areas of NMR and MRI. The chapters of each of these handbooks will comprise a carefully chosen selection of articles from eMagRes. In consultation with the eMagRes Editorial Board, the EMR Handbooks / eMagRes Handbooks are coherently planned in advance by specially-selected Editors, and new articles are written (together with updates of some already existing articles) to give appropriate complete coverage. The handbooks are intended to be of value and interest to research students, postdoctoral fellows and other researchers learning about the scientific area in question and undertaking relevant experiments, whether in academia or industry. Have the content of this Handbook and the complete content of eMagRes at your fingertips! Visit: www.wileyonlinelibrary.com/ref/eMagRes View other eMagRes publications here
Download or read book Magnetic Resonance Imaging written by Stewart C. Bushong and published by Elsevier Health Sciences. This book was released on 2003-01-01 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dette er en grundlæggende lærebog om konventionel MRI samt billedteknik. Den begynder med et overblik over elektricitet og magnetisme, herefter gives en dybtgående forklaring på hvordan MRI fungerer og her diskuteres de seneste metoder i radiografisk billedtagning, patientsikkerhed m.v.
Download or read book Introduction to RF Propagation written by John S. Seybold and published by John Wiley & Sons. This book was released on 2005-10-03 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: An introduction to RF propagation that spans all wireless applications This book provides readers with a solid understanding of the concepts involved in the propagation of electromagnetic waves and of the commonly used modeling techniques. While many books cover RF propagation, most are geared to cellular telephone systems and, therefore, are limited in scope. This title is comprehensive-it treats the growing number of wireless applications that range well beyond the mobile telecommunications industry, including radar and satellite communications. The author's straightforward, clear style makes it easy for readers to gain the necessary background in electromagnetics, communication theory, and probability, so they can advance to propagation models for near-earth, indoor, and earth-space propagation. Critical topics that readers would otherwise have to search a number of resources to find are included: * RF safety chapter provides a concise presentation of FCC recommendations, including application examples, and prepares readers to work with real-world propagating systems * Antenna chapter provides an introduction to a wide variety of antennas and techniques for antenna analysis, including a detailed treatment of antenna polarization and axial ratio; the chapter contains a set of curves that permit readers to estimate polarization loss due to axial ratio mismatch between transmitting and receiving antennas without performing detailed calculations * Atmospheric effects chapter provides curves of typical atmospheric loss, so that expected loss can be determined easily * Rain attenuation chapter features a summary of how to apply the ITU and Crane rain models * Satellite communication chapter provides the details of earth-space propagation analysis including rain attenuation, atmospheric absorption, path length determination and noise temperature determination Examples of widely used models provide all the details and information needed to allow readers to apply the models with confidence. References, provided throughout the book, enable readers to explore particular topics in greater depth. Additionally, an accompanying Wiley ftp site provides supporting MathCad files for select figures in the book. With its emphasis on fundamentals, detailed examples, and comprehensive coverage of models and applications, this is an excellent text for upper-level undergraduate or graduate students, or for the practicing engineer who needs to develop an understanding of propagation phenomena.
Download or read book Introduction to RF Equipment and System Design written by Pekka Eskelinen and published by Artech House. This book was released on 2004 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: An excellent resource for engineers and technicians alike, this practical design guide offers a comprehensive and easy-to-understand overview of the most important aspects and components of radio frequency equipment and systems. The book applies theoretical fundamentals to real-world issues, heavily relying on examples from recent design projects. Key discussions include system design schemes, circuits and components for system evaluations and design, RF measurement instrumentation, antennas and associated hardware, and guidelines for purchasing test equipment. The book also serves as a valuable on-the-job training resources for sales engineers and a graduate-level text for courses in this area.
Download or read book The Design and Implementation of Low Power CMOS Radio Receivers written by Derek Shaeffer and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is hardly a profound observation to note that we remain in the midst of a wireless revolution. In 1998 alone, over 150 million cell phones were sold worldwide, representing an astonishing 50% increase over the previous year. Maintaining such a remarkable growth rate requires constant innovation to decrease cost while increasing performance and functionality. Traditionally, wireless products have depended on a mixture of semicond- tor technologies, spanning GaAs, bipolar and BiCMOS, just to name a few. A question that has been hotly debated is whether CMOS could ever be suitable for RF applications. However, given the acknowledged inferiority of CMOS transistors relative to those in other candidate technologies, it has been argued by many that “CMOS RF” is an oxymoron, an endeavor best left cloistered in the ivory towers of academia. In rebuttal, there are several compelling reasons to consider CMOS for wi- less applications. Aside from the exponential device and density improvements delivered regularly by Moore’s law, only CMOS offers a technology path for integrating RF and digital elements, potentially leading to exceptionally c- pact and low-cost devices. To enable this achievement, several thorny issues need to be resolved. Among these are the problem of poor passive com- nents, broadband noise in MOSFETs, and phase noise in oscillators made with CMOS. Beyond the component level, there is also the important question of whether there are different architectural choices that one would make if CMOS were used, given the different constraints.
Download or read book Ultra Low Power FM UWB Transceivers for IoT written by Vladimir Kopta and published by CRC Press. This book was released on 2022-09-01 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past two decades we have witnessed the increasing popularity of the internet of things. The vision of billions of connected objects, able to interact with their environment, is the key driver directing the development of future communication devices. Today, power consumption as well as the cost and size of radios remain some of the key obstacles towards fulfilling this vision. Ultra-Low Power FM-UWB Transceivers for IoT presents the latest developments in the field of low power wireless communication. It promotes the FM-UWB modulation scheme as a candidate for short range communication in different IoT scenarios. The FM-UWB has the potential to provide exactly what is missing today. This spread spectrum technique enables significant reduction in transceiver complexity, making it smaller, cheaper and more energy efficient than most alternative options. The book provides an overview of both circuit-level and architectural techniques used in low power radio design, with a comprehensive study of state-of-the-art examples. It summarizes key theoretical aspects of FM-UWB with a glimpse at potential future research directions. Finally, it gives an insight into a full FM-UWB transceiver design, from system level specifications down to transistor level design, demonstrating the modern power reduction circuit techniques. Ultra-Low Power FM-UWB Transceivers for IoT is a perfect text and reference for engineers working in RF IC design and wireless communication, as well as academic staff and graduate students engaged in low power communication systems research.
Download or read book Op Amps for Everyone written by Ron Mancini and published by Newnes. This book was released on 2003 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: The operational amplifier ("op amp") is the most versatile and widely used type of analog IC, used in audio and voltage amplifiers, signal conditioners, signal converters, oscillators, and analog computing systems. Almost every electronic device uses at least one op amp. This book is Texas Instruments' complete professional-level tutorial and reference to operational amplifier theory and applications. Among the topics covered are basic op amp physics (including reviews of current and voltage division, Thevenin's theorem, and transistor models), idealized op amp operation and configuration, feedback theory and methods, single and dual supply operation, understanding op amp parameters, minimizing noise in op amp circuits, and practical applications such as instrumentation amplifiers, signal conditioning, oscillators, active filters, load and level conversions, and analog computing. There is also extensive coverage of circuit construction techniques, including circuit board design, grounding, input and output isolation, using decoupling capacitors, and frequency characteristics of passive components. The material in this book is applicable to all op amp ICs from all manufacturers, not just TI. Unlike textbook treatments of op amp theory that tend to focus on idealized op amp models and configuration, this title uses idealized models only when necessary to explain op amp theory. The bulk of this book is on real-world op amps and their applications; considerations such as thermal effects, circuit noise, circuit buffering, selection of appropriate op amps for a given application, and unexpected effects in passive components are all discussed in detail. *Published in conjunction with Texas Instruments *A single volume, professional-level guide to op amp theory and applications *Covers circuit board layout techniques for manufacturing op amp circuits.
Download or read book Radio Systems Engineering written by Héctor J. De Los Santos and published by Springer. This book was released on 2014-08-19 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended for readers who already have knowledge of devices and circuits for radio-frequency (RF) and microwave communication and are ready to study the systems engineering-level aspects of modern radio communications systems. The authors provide a general overview of radio systems with their components, focusing on the analog parts of the system and their non-idealities. Based on the physical functionality of the various building blocks of a modern radio system, block parameters are derived, which allows the examination of their influence on the overall system performance. The discussion is complemented by tutorial exercises based on the Agilent SystemVue electronic system-level (ESL) design software. With these tutorials, readers gain practical experience with realistic design examples of radio transmission systems for communications and radar sensing. The tutorials cover state-of-the-art system standards and applications and consider the characteristics of typical radio-frequency hardware components. For all tutorials, a comprehensive description of the tasks, including some hints to the solutions, is provided. The readers are then able to perform these tasks independently. A complete set of simulation models and solutions to the tutorial exercises is given.
Download or read book 2021 IEEE Radio Frequency Integrated Circuits Symposium RFIC written by IEEE Staff and published by . This book was released on 2021-06-07 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: RFIC is the premier IC Conference focused on the latest developments in RF Microwave, and Millimeter Wave Integrated Circuit Technology and Innovation
Download or read book Microwave Circuit Design Using Linear and Nonlinear Techniques written by George D. Vendelin and published by John Wiley & Sons. This book was released on 2005-10-03 with total page 1080 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ultimate handbook on microwave circuit design with CAD. Full of tips and insights from seasoned industry veterans, Microwave Circuit Design offers practical, proven advice on improving the design quality of microwave passive and active circuits-while cutting costs and time. Covering all levels of microwave circuit design from the elementary to the very advanced, the book systematically presents computer-aided methods for linear and nonlinear designs used in the design and manufacture of microwave amplifiers, oscillators, and mixers. Using the newest CAD tools, the book shows how to design transistor and diode circuits, and also details CAD's usefulness in microwave integrated circuit (MIC) and monolithic microwave integrated circuit (MMIC) technology. Applications of nonlinear SPICE programs, now available for microwave CAD, are described. State-of-the-art coverage includes microwave transistors (HEMTs, MODFETs, MESFETs, HBTs, and more), high-power amplifier design, oscillator design including feedback topologies, phase noise and examples, and more. The techniques presented are illustrated with several MMIC designs, including a wideband amplifier, a low-noise amplifier, and an MMIC mixer. This unique, one-stop handbook also features a major case study of an actual anticollision radar transceiver, which is compared in detail against CAD predictions; examples of actual circuit designs with photographs of completed circuits; and tables of design formulae.
Download or read book Nmr Probeheads For Biophysical And Biomedical Experiments Theoretical Principles And Practical Guidelines 2nd Edition written by Joel Mispelter and published by World Scientific Publishing Company. This book was released on 2015-05-27 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt: NMR Probeheads for Biophysical and Biomedical Experiments 2nd Edition is essential reading for anyone in the field of NMR or MRI, from students to medical or biological scientists performing experiments under certain physical and/or geometrical conditions, unattainable by conventional or available probes. The material guides the reader through the most basic and comprehensive stages in accomplishing a correct probe design, from a very basic oscillating circuit to much more elaborate designs.This new edition has been revised and updated to include a chapter dedicated to RF components, which are commonly used for probes realization and their frequency-dependent characteristics. Another completely revised chapter concerns the multiple coil systems and discusses arrays coils, different decoupling methods, and some principles for interfacing coils with low-noise preamplifiers. The principles of linear circuit analysis are presented in a dedicated chapter. Last but not least, accompanying files containing updated software for probe design have been made available from the publisher's website.
Download or read book Brain and Human Body Modeling written by Sergey Makarov and published by Springer Nature. This book was released on 2019-08-27 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book describes modern applications of computational human modeling with specific emphasis in the areas of neurology and neuroelectromagnetics, depression and cancer treatments, radio-frequency studies and wireless communications. Special consideration is also given to the use of human modeling to the computational assessment of relevant regulatory and safety requirements. Readers working on applications that may expose human subjects to electromagnetic radiation will benefit from this book’s coverage of the latest developments in computational modelling and human phantom development to assess a given technology’s safety and efficacy in a timely manner. Describes construction and application of computational human models including anatomically detailed and subject specific models; Explains new practices in computational human modeling for neuroelectromagnetics, electromagnetic safety, and exposure evaluations; Includes a survey of modern applications for which computational human models are critical; Describes cellular-level interactions between the human body and electromagnetic fields.
