Design Stripline Circulator at 2.5 Ghz for Radar Applications
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Few Electron Paramagnetic Resonances Detection On
FEW ELECTRON PARAMAGNETIC RESONANCES DETECTION TECHNIQUES ON THE RUBY SURFACE By Xiying Li Submitted in partial fulfillment of the requirements For the degree of Doctor of Philosophy Dissertation Adviser: Dr. Massood Tabib-Azar Co-Adviser: Dr. J. Adin Mann, Jr. Department of Electrical Engineering and Computer Science CASE WESTERN RESERVE UNIVERSITY August, 2005 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the dissertation of ______________________________________________________ candidate for the Ph.D. degree *. (signed)_______________________________________________ (chair of the committee) ________________________________________________ ________________________________________________ ________________________________________________ ________________________________________________ ________________________________________________ (date) _______________________ *We also certify that written approval has been obtained for any proprietary material contained therein. Table of Contents TABLE OF CONTENTS ................................................................................................................................. II LIST OF FIGURES ...................................................................................................................................... IV ABSTRACT............................................................................................................................................... VII CHAPTER 1 INTRODUCTION .................................................................................................................1 -
Aperture-Coupled Stripline-To-Waveguide Transitions for Spatial Power Combining
ACES JOURNAL, VOL. 18, NO. 4, NOVEMBER 2003 33 Aperture-Coupled Stripline-to-Waveguide Transitions for Spatial Power Combining Chris W. Hicks∗, Alexander B. Yakovlev#,andMichaelB.Steer+ ∗Naval Air Systems Command, RF Sensors Division 4.5.5, Patuxent River, MD 20670 #Department of Electrical Engineering, The University of Mississippi, University, MS 38677-1848 +Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, NC 27695-7914 Abstract power. However, tubes are bulky, costly, require high operating voltages, and have a short lifetime. As an A full-wave electromagnetic model is developed and alternative, solid-state devices offer several advantages verified for a waveguide transition consisting of slotted such as, lightweight, smaller size, wider bandwidths, rectangular waveguides coupled to a strip line. This and lower operating voltages. These advantages lead waveguide-based structure represents a portion of the to lower cost because systems can be constructed us- planar spatial power combining amplifier array. The ing planar fabrication techniques. However, as the fre- electromagnetic simulator is developed to analyze the quency increases, the output power of solid-state de- stripline-to-slot transitions operating in a waveguide- vices decreases due to their small physical size. There- based environment in the X-band. The simulator is fore, to achieve sizable power levels that compete with based on the method of moments (MoM) discretiza- those generated by vacuum tubes, several solid-state tion of the coupled system of integral equations with devices can be combined in an array. Conventional the piecewise sinusodial testing and basis functions in power combiners are effectively limited in the num- the electric and magnetic surface current density ex- ber of devices that can be combined. -
Lowpass Lumped-Element Coplanar Waveguide-To- Coplanar Stripline Transitions
LOWPASS LUMPED-ELEMENT COPLANAR WAVEGUIDE-TO- COPLANAR STRIPLINE TRANSITIONS Yo-Shen Lin1 and Chun Hsiung Chen2 1Department of Electrical Engineering, National Central University, Chungli 320, Taiwan, R.O.C. (email: [email protected]) 2Department of Electrical Engineering and Graduate Institute of Communication Engineering, National Taiwan University, Taipei 106, Taiwan, R.O.C. (email: [email protected]) ABSTRACT The lowpass coplanar waveguide-to-coplanar stripline transitions are proposed, using planar lumped-elements to realize the filter prototypes in the transition structures. The proposed transitions are very compact and can provide the combined functions of transition and filter. Simple equivalent-circuit models based on closed-form expressions are also established, from which the characteristics of various lowpass lumped-element transitions are investigated. INTRODUCTION Coplanar waveguide (CPW) and coplanar stripline (CPS) are widely used as building blocks in the design of uniplanar MMIC's [1]. To fully utilize the exclusive features of CPW and CPS, an effective interconnection between them is of crucial importance. This may allow the choice of different uniplanar line-based circuit elements in different parts of a system such that maximum circuit integration and optimal system performance may be accomplished. Various CPW-to-CPS transitions have been developed [2]-[7]. Most of these conventional transitions have bandpass behaviors [2]-[4]. The broadband transition [5] utilizing a slotline open structure has a lowpass frequency response but its insertion loss increases only gradually as the operating frequency increases. The ideally all-pass double-Y junction balun [2], in practice, also features a gradually increasing insertion loss with frequency. -
Short Course on Isolators and FM Antennas
Shively Labs® Short Course on Isolators and FM Antennas Introduction Isolators have been around for more than 50 years, and during that time have been used in applications across a wide electromagnetic spectrum. Until recently, however, they have not been widely used in the FM band, and the uses that did exist did not require the development of units that could handle more than a few hundred watts. Now, as stations begin to go on the air with digital radio in ever increasing numbers, FM isolators are receiving a great deal of attention as a key component in a number of IBOC installations. Early deployment has been limited by the low power ratings of the available units, but power capacity is rising quickly as manufacturers devote time and resources to developing isolators specifically to address the needs of the new FM market. On the other side of the fence, RF engineers are rapidly familiarizing themselves with the principles of isolators and their advantages and limitations. As with any emerging technology, integrating vari- as advances in power rating sometimes came with ous components of the FM IBOC transmission chain conditions that limited the usefulness of the units. has had both successes and setbacks. Isolators have Size, weight, and cooling requirements that might be been involved in both. As with all test sites, some of suitable at some sites made the units impractical at the early deployments could be said to be more edu- others. For example, in at least one application, an cational than successful, but as often as not these isolator capable of handling the return power of the setbacks were not so much the fault of the isolators station was only efficient enough to do so when it themselves as of the inexperience of the engineers was warmed up. -
Electron Paramagnetic Resonance Theory E.C. Duin
Wilfred R. Hagen Electron Paper: EPR spectroscopy as a probe of metal centres in Paramagnetic biological systems (2006) Dalton Trans. 4415-4434 Resonance Book: Theory Biomolecular EPR Spectroscopy (2009) Fred Hagen completed his PhD on EPR of metalloproteins at the University of Amsterdam in 1982 with S.P.J. Albracht E.C. Duin and E.C. Slater. 1 3 EPR, the Technique…. Spectral Simulations • Molecular EPR spectroscopy is a method to look at the • The book ‘Biomolecular EPR spectroscopy’ comes with a structure and reactivity of molecules. suite of programs for basic manipulation and analysis of EPR data which will be used in this class. • EPR is limited to paramagnetic substances (unpaired electrons). When used in the study of metalloproteins not the • Software: www.bt.tudelft.nl/biomolecularEPRspectroscopy whole molecule is observed but only that small part where the paramagnetism is located. Isotropic Radicals • This is usually the central place of action – the active site of Simple Spectrum Single Integer Signal enzyme catalysis. • Sensitivity: 10 μM and up. Hyperfine Spectrum GeeStrain-5 • Naming: Electron paramagnetic resonance (EPR), electron Visual Rhombo spin resonance (ESR), electron magnetic resonance (EMR) EPR File Converter EPR Editor 2 4 1 BYOS (Bring Your Own Sample) EPR Theory A Free Electron in Vacuo Learn how to use the EPR spectrometer and apply your new knowledge to obtain valuable Free, unpaired electron in space: information on a real EPR sample. electron spin - magnetic moment 5 7 Discovery A Free Electron in a Magnetic Field In 1944, E.K. Zavoisky discovered magnetic resonance. Actually it was EPR on CuCl2. -
Proposed New Circulator with Coplanar Waveguide Structure
Trans. Magn. Soc. Japan, 4, 56-59 (2004) Proposed New Circulator with Coplanar Waveguide Structure S. Yamamoto, K. Shitamitsu, H. Kurisu, M. Matsuura, K. Oshiro *,H. Mikami**,and S. Fujii** Facultyof Engineering,Yamaguchi Univ., 2-16-1 Tokiwadai,Ube, Yamaguchi 755-8611 *Ch ugoku TechnologyPromotion Center, 4-33 Komachi, Nakaku, Hiroshima 730-0041 **Hi tachi Metals,Ltd. , 5200 Mikajiri,Kumagaya, Saitama 360-0843 A small circulator with a coplanar waveguide structure process. Wen and Bayard have reported that their was confirmed to have nonreciprocal transmission two-port-type CPW circulator operating at 7 GHz needs characteristics by a high-frequency electromagnetic an internal magnetic field of more than 170 kA/m and simulation based on a three-dimensional finite element that the device width is as long as 20 mm3).4). Ogasawara method. The circulator consists of a hexagonal YIG reported that Y-junction circulators with CPW ferrite substrate and a Y-junction with coplanar successfully operated at some frequencies. However, no waveguide transmission lines. Operating at 7 GHz, the detail of the circulators and their transmission circulator has an insertion loss •bS21•b of 0.69 dB, isolation characteristics were given in his papers). Since the |S31| of 32.7 dB, retum loss |S11| of 32.2 dB, a皿d abovementioned pioneering work, no significant progress bandwidth of 77 MHz. The nonreciprocal operation of the in research on CPW circulators has been reported. circulator is attributed to the wavy nonuniform The purpose of this study is to propose a small distribution of the electric field in the YIG ferrite circulator with a CPW structure and operation frequency substrate. -
The Stripline Circulator Theory and Practice
The Stripline Circulator Theory and Practice By J. HELSZAJN The Stripline Circulator The Stripline Circulator Theory and Practice By J. HELSZAJN Copyright # 2008 by John Wiley & Sons, Inc. All rights reserved Published by John Wiley & Sons, Inc. Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 750-4470, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http:// www.wiley.com/go/permission. Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. -
97/$10.00 260 Ii
Lumped-element Sections for Modeling Coupling Between High-Speed Digital and I/O Lines W. Cui, H. Shi, X. Luo, F. Sha*, J.L. Drewniak, T.P. Van Doren and T. Anderson** ElectromagneticCompatibility Laboratory University of Missouri-Rolla Rolla, MCI 65401 * Northern Jiao Tong University EMC ResearchSection Beijing 100044,P.R.China * * HP-EEsof Division Hewlett-PackardCo. SantaRosa, CA 95403 Abstract: Lumped-elementsections are used for modeling designstage to estimateEM1 and minimize the noise coupling coupling betweenhigh-speed digital and I/O lines on printed to I/O lines on the PCB. As digital designs become more circuit boards (PCBs) in this paper. Radiatedelectromagnetic dense, flexibility in trace routing is reduced. Adherence to interference(EMI) is investigatedwhen the I/O line going off simple design maxims for avoiding adjacent segmentsof an the board is driven as an unintentional, but effective antenna. I/O line and a high-speeddigital line becomesmore difficult. Simulated results are compared with measurementsfor A meansfor estimatingEM1 at the design stageis desirableto coupled lines. A suitable number of lumped-elementsections maintainrouting flexibility while minimizing EM1 risk. for modeling is chosen based on the line length and the highestfrequency of interest. The three essentialcomponents for estimating EM1 resulting from coupling to I/O lines are suitable sourceand load models, a coupled transmission-line model, and an EM1 antenna I. INTR~DUC~~N model. Of particular interest at this stage are models for the coupled transmission lines, and the EM1 antenna. Two As the speed of digital designs continues to increase, approaches have been previously pursued for modeling unintentionalradiation from cablesattached to PCBs becomes coupled transmission-lines.One technique is to decouple the problematic.For clock speedsless than 50 MHz, a typical 1 m lines in the frequency domain by modal decomposition [l]. -
A Full-Duplex Radio Using a CMOS Non-Magnetic Circulator Achieving +95 Db Overall SIC
A Full-Duplex Radio Using a CMOS Non-Magnetic Circulator Achieving +95 dB Overall SIC Aravind Nagulu, Tingjun Chen, Gil Zussman, and Harish Krishnaswamy Department of Electrical Engineering, Columbia University, New York, NY 10027, USA. (Invited Paper) Abstract—Full-duplex (FD) wireless is an emerging wireless communication paradigm where the transmitter and the receiver operate simultaneously at the same frequency. One major challenge in realizing FD wireless is the interference of the TX signal saturating the receiver, commonly referred to self-interference (SI). Traditionally, self-interference cancellation (SIC) is achieved in the antenna, RF/analog, and digital domains. In the antenna domain, SIC can be achieved using a pair of separate TX and RX antennas, or using a single antenna shared by the TX and RX through a magnetic circulator, which is usually bulky, expensive, and not integrable with CMOS. Recent advances, however, have shown the feasibility of realizing high-performance non-reciprocal circulators in CMOS based on spatio-temporal modulation. In this work, we demonstrate a high Fig. 1. High power handing circulator with inductor-free antenna balancing. power handling FD radio using a USRP SDR which employs SIC (i) at the antenna interface using a watt-level power-handling recently, architectural advances have enabled these CMOS CMOS integrated, magnetic-free circulator, (ii) in the RF domain time-modulated circulators to achieve watt-level transmitter using a compact RF canceler, and (iii) in the digital domain. Our power handling and wideband and tunable isolation [5]. In prototyped FD radio achieves +95 dB overall SIC at +15 dBm this work, we present an FD radio using this highly linear TX power level. -
RF / Microwave PC Board Design and Layout
RF / Microwave PC Board Design and Layout Rick Hartley L-3 Avionics Systems [email protected] 1 RF / Microwave Design - Contents 1) Recommended Reading List 2) Basics 3) Line Types and Impedance 4) Integral Components 5) Layout Techniques / Strategies 6) Power Bus 7) Board Stack-Up 8) Skin Effect and Loss Tangent 9) Shields and Shielding 10) PCB Materials, Fabrication and Assembly 2 RF / Microwave - Reading List PCB Designers – • Transmission Line Design Handbook – Brian C. Wadell (Artech House Publishers) – ISBN 0-89006-436-9 • HF Filter Design and Computer Simulation – Randall W. Rhea (Noble Publishing Corp.) – ISBN 1-884932-25-8 • Partitioning for RF Design – Andy Kowalewski - Printed Circuit Design Magazine, April, 2000. • RF & Microwave Design Techniques for PCBs – Lawrence M. Burns - Proceedings, PCB Design Conference West, 2000. 3 RF / Microwave - Reading List RF Design Engineers – • Microstrip Lines and Slotlines – Gupta, Garg, Bahl and Bhartia. Artech House Publishers (1996) – ISBN 0-89006-766-X • RF Circuit Design – Chris Bowick. Newnes Publishing (1982) – ISBN 0-7506-9946-9 • Introduction to Radio Frequency Design – Wes Hayward. The American Radio Relay League Inc. (1994) – ISBN 0-87259-492-0 • Practical Microwaves – Thomas S. Laverghetta. Prentice Hall, Inc. (1996) – ISBN 0-13-186875-6 4 RF / Microwave Design - Basics ) RF and Microwave Layout encompasses the Design of Analog Based Circuits in the range of Hundreds of Megahertz (MHz) to Many Gigahertz (GHz). ) RF actually in the 500 MHz - 2 GHz Band. (Design Above 100 MHz considered RF.) ) Microwave above 2 GHZ. 5 RF / Microwave Design - Basics ) Unlike Digital, Analog Signals can be at any Voltage and Current Level (Between their Min & Max), at any point in Time. -
Quasi-Circulator Using an Asymmetric Coupler for Tx Leakage Cancellation
electronics Article Quasi-Circulator Using an Asymmetric Coupler for Tx Leakage Cancellation Bo-Yoon Yoo, Jae-Hyun Park and Jong-Ryul Yang * ID Department of Electronic Engineering, Yeungnam University, Gyeongbuk 38541, Korea; [email protected] (B.-Y.Y.); [email protected] (J.-H.P.) * Correspondence: [email protected]; Tel.: +82-53-810-2495 Received: 20 July 2018; Accepted: 31 August 2018; Published: 1 September 2018 Abstract: A quasi-circulator is proposed by using an asymmetric coupler with high isolation between the transmitting (Tx) and receiving (Rx) ports. The proposed quasi-circulator consists of quarter-wave transmission lines, which have unbalanced characteristic impedances and the terminated port, which is purposely unmatched with the reference impedance in the coupler. The port compensates for the asymmetric impedances of the coupler using the proposed design parameter. Because of its asymmetric structure and the usage of the unmatched port, the proposed circulator can be accurately designed to have high Tx–Rx isolation without increasing the signal losses in the Tx and Rx paths at the operating frequency. The proposed quasi-circulators show isolation improvements of 9.07 dB at 2.45 GHz and 7.95 dB at 24.125 GHz compared with conventional circulators using the symmetric couplers. The characteristic improvement of the proposed quasi-circulator was demonstrated by the increase of the detectable range of the 2.45 GHz Doppler radar sensor with the quasi-circulator. Keywords: quasi-circulator; asymmetric coupler; Tx leakage cancellation; planar circulator; hybrid coupler design; passive components 1. Introduction In electromagnetic-wave application systems such as radar sensors and wireless communication systems, the number and size of antennas should be considered in the implementation of the miniaturized module [1–4]. -
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Progress In Electromagnetics Research Letters, Vol. 7, 139–148, 2009 A CANCELLATION NETWORK FOR FULL-DUPLEX FRONT END CIRCUIT Y. K. Chan and V. C. Koo Faculty of Engineering & Technology Multimedia University Jalan Ayer Keroh Lama, Bukit Beruang, Melaka 75450, Malaysia B. K. Chung and H. T. Chuah University Tungku Abdul Rahman 13, Jalan 13/6, Petaling Jaya, Selangor 46200, Malaysia Abstract—A circulator is needed in a C-band airborne synthetic aperture radar system which employs single antenna configuration. The circulator provides full-duplex capability to transmit high- power RF signal and receive the echo signal via the same antenna simultaneously. Commercially available circulators with moderate isolation are inadequate for this application. An innovative Cancellation Network (CN) has been designed to enhance the performance of the conventional circulator. This paper highlights the conceptual design and measurement results of the CN. An improvement of more than 27 dB has been achieved. 1. INTRODUCTION A circulator is a three-port non-reciprocal device that passes microwave energy in a forward direction but provides isolation in reverse direction. Circulator has been widely used in transmit and receive (T/R) modules of communication and radar system as a duplexer [1, 2]. Other applications include time delay switching application [3] and phase shifter [4]. Conventional ferrite circulators are constructed with permanent magnets and ferrite materials on microstrip circuit. The non-reciprocal action is brought by gyromagnetic action [1]. A new approach for realization of microwave circulator makes use of the non- reciprocal properties of microwave field effect transistor [5–7]. This Corresponding author: Y.