25. Antennas II
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Study of Radiation Patterns Using Modified Design of Yagi-Uda Antenna G
Adv. Eng. Tec. Appl. 5, No. 1, 7-9 (2016) 7 Advanced Engineering Technology and Application An International Journal http://dx.doi.org/10.18576/aeta/050102 Study of Radiation Patterns Using Modified Design of Yagi-Uda Antenna G. M. Thakur1, V. B. Sanap2,* and B. H. Pawar1. PI, Wireless section, DPW &Adl DG office, Pune (M.S.), India. Yeshwantrao Chavan College, Sillod Dist Aurangabad (M.S.), India. Received: 8 Aug. 2015, Revised: 20 Oct. 2015, Accepted: 28 Oct. 2015. Published online: 1 Jan. 2016. Abstract: Antenna is very important in wireless communication system. Among the most prevalent antennas, Yagi-Uda antenna is widely used. To improve the antenna gain and directivity, design of antenna is always important. In this paper, the Yagi Uda antenna is modified by adding two more reflectors instead of single and the gain, directivity & radiation pattern were studied. This antenna is designed to give better gain in one particular direction as well as somewhat reduced gain in other directions. The direction of "reduced gain" and gain at particular direction are not controllable in Yagi Uda. This paper provides a design which modifies radiation pattern of Yagi as per user requirement. The experiment is carried out at 157 MHz and all readings are taken for vertical polarization, with the help of Radio Communication Monitor. Keywords: Wireless communication, Yagi-Uda, Communication Service Monitor, Vertical polarization. 1 Introduction three) are used. The said antenna is designed with following set of parameters, Antennas have numerous advantages such as they can be Type:- Yagi-Uda antenna with additional two suitably used for wide range of applications such as reflectors wireless communications, satellite communications, pattern Input :- FM modulated signal of 157 MHz, with stability combining and antenna arrays. -
Chapter 22 Fundamentalfundamental Propertiesproperties Ofof Antennasantennas
ChapterChapter 22 FundamentalFundamental PropertiesProperties ofof AntennasAntennas ECE 5318/6352 Antenna Engineering Dr. Stuart Long 1 .. IEEEIEEE StandardsStandards . Definition of Terms for Antennas . IEEE Standard 145-1983 . IEEE Transactions on Antennas and Propagation Vol. AP-31, No. 6, Part II, Nov. 1983 2 ..RadiationRadiation PatternPattern (or(or AntennaAntenna Pattern)Pattern) “The spatial distribution of a quantity which characterizes the electromagnetic field generated by an antenna.” 3 ..DistributionDistribution cancan bebe aa . Mathematical function . Graphical representation . Collection of experimental data points 4 ..QuantityQuantity plottedplotted cancan bebe aa . Power flux density W [W/m²] . Radiation intensity U [W/sr] . Field strength E [V/m] . Directivity D 5 . GraphGraph cancan bebe . Polar or rectangular 6 . GraphGraph cancan bebe . Amplitude field |E| or power |E|² patterns (in linear scale) (in dB) 7 ..GraphGraph cancan bebe . 2-dimensional or 3-D most usually several 2-D “cuts” in principle planes 8 .. RadiationRadiation patternpattern cancan bebe . Isotropic Equal radiation in all directions (not physically realizable, but valuable for comparison purposes) . Directional Radiates (or receives) more effectively in some directions than in others . Omni-directional nondirectional in azimuth, directional in elevation 9 ..PrinciplePrinciple patternspatterns . E-plane . H-plane Plane defined by H-field and Plane defined by E-field and direction of maximum direction of maximum radiation radiation (usually coincide with principle planes of the coordinate system) 10 Coordinate System Fig. 2.1 Coordinate system for antenna analysis. 11 ..RadiationRadiation patternpattern lobeslobes . Major lobe (main beam) in direction of maximum radiation (may be more than one) . Minor lobe - any lobe but a major one . Side lobe - lobe adjacent to major one . -
Radiometry and the Friis Transmission Equation Joseph A
Radiometry and the Friis transmission equation Joseph A. Shaw Citation: Am. J. Phys. 81, 33 (2013); doi: 10.1119/1.4755780 View online: http://dx.doi.org/10.1119/1.4755780 View Table of Contents: http://ajp.aapt.org/resource/1/AJPIAS/v81/i1 Published by the American Association of Physics Teachers Related Articles The reciprocal relation of mutual inductance in a coupled circuit system Am. J. Phys. 80, 840 (2012) Teaching solar cell I-V characteristics using SPICE Am. J. Phys. 79, 1232 (2011) A digital oscilloscope setup for the measurement of a transistor’s characteristic curves Am. J. Phys. 78, 1425 (2010) A low cost, modular, and physiologically inspired electronic neuron Am. J. Phys. 78, 1297 (2010) Spreadsheet lock-in amplifier Am. J. Phys. 78, 1227 (2010) Additional information on Am. J. Phys. Journal Homepage: http://ajp.aapt.org/ Journal Information: http://ajp.aapt.org/about/about_the_journal Top downloads: http://ajp.aapt.org/most_downloaded Information for Authors: http://ajp.dickinson.edu/Contributors/contGenInfo.html Downloaded 07 Jan 2013 to 153.90.120.11. Redistribution subject to AAPT license or copyright; see http://ajp.aapt.org/authors/copyright_permission Radiometry and the Friis transmission equation Joseph A. Shaw Department of Electrical & Computer Engineering, Montana State University, Bozeman, Montana 59717 (Received 1 July 2011; accepted 13 September 2012) To more effectively tailor courses involving antennas, wireless communications, optics, and applied electromagnetics to a mixed audience of engineering and physics students, the Friis transmission equation—which quantifies the power received in a free-space communication link—is developed from principles of optical radiometry and scalar diffraction. -
ECE 5011: Antennas
ECE 5011: Antennas Course Description Electromagnetic radiation; fundamental antenna parameters; dipole, loops, patches, broadband and other antennas; array theory; ground plane effects; horn and reflector antennas; pattern synthesis; antenna measurements. Prior Course Number: ECE 711 Transcript Abbreviation: Antennas Grading Plan: Letter Grade Course Deliveries: Classroom Course Levels: Undergrad, Graduate Student Ranks: Junior, Senior, Masters, Doctoral Course Offerings: Spring Flex Scheduled Course: Never Course Frequency: Every Year Course Length: 14 Week Credits: 3.0 Repeatable: No Time Distribution: 3.0 hr Lec Expected out-of-class hours per week: 6.0 Graded Component: Lecture Credit by Examination: No Admission Condition: No Off Campus: Never Campus Locations: Columbus Prerequisites and Co-requisites: Prereq: 3010 (312), or Grad standing in Engineering, Biological Sciences, or Math and Physical Sciences. Exclusions: Not open to students with credit for 711. Cross-Listings: Course Rationale: Existing course. The course is required for this unit's degrees, majors, and/or minors: No The course is a GEC: No The course is an elective (for this or other units) or is a service course for other units: Yes Subject/CIP Code: 14.1001 Subsidy Level: Doctoral Course Programs Abbreviation Description CpE Computer Engineering EE Electrical Engineering Course Goals Teach students basic antenna parameters, including radiation resistance, input impedance, gain and directivity Expose students to antenna radiation properties, propagation (Friis transmission -
WDP.2458.25.4.B.02 Linear Polarization Wifi Dual Bands Patch
SPECIFICATION PATENT PENDING Part No. : WDP.2458.25.4.B.02 Product Name : Wi-Fi Dual-band 2.4/5 GHz Embedded Ceramic Patch Antenna 6dBi+ at 2.4GHz 6dBi+ on 5 to 6 GHz Features : 25mm*25mm*4mm 2400MHz to 2500MHz/5150MHz to 5850MHz Pin Type Supports IEEE 802.11 Dual-band Wi-Fi systems Dual linear polarization Tuned for 70x70mm ground plane RoHS & REACH Compliant SPE-14-8-039/B/WY Page 1 of 14 1. Introduction This unique patent pending high gain, high efficiency embedded ceramic patch antenna is designed for professional Wi-Fi dual-band IEEE 802.11 applications. It is mounted via pin and double-sided adhesive. The passive patch offers stable high gain response from 4 dBi to 6dBi on the 2.4GHz band and from 5dBi to 8dBi on the 5 ~6 GHz band. Efficiency values are impressive also across the bands with on average 60%+. The WDP.25’s high gain, high efficiency performance is the perfect solution for directional dual-band WiFi application which need long range but which want to use small compact embedded antennas. The much higher gain and efficiency of the WDP.25 over smaller less efficient more omni-directional chip antennas (these typically have no more than 2dBi gain, 30% efficiencies) means it can deliver much longer range over a wide sector. Typical applications are • Access Points • Tablets • High definition high throughput video streaming routers • High data MIMO bandwidth routers • Automotive • Home and industrial in-wall WiFi automation • Drones/Quad-copters • UAV • Long range WiFi remote control applications The WDP patch antenna has two distinct linear polarizations, on the 2.4 and 5GHz bands, increasing isolation between bands. -
Development of Earth Station Receiving Antenna and Digital Filter Design Analysis for C-Band VSAT
INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 3, ISSUE 6, JUNE 2014 ISSN 2277-8616 Development of Earth Station Receiving Antenna and Digital Filter Design Analysis for C-Band VSAT Su Mon Aye, Zaw Min Naing, Chaw Myat New, Hla Myo Tun Abstract: This paper describes the performance improvement of C-band VSAT receiving antenna. In this work, the gain and efficiency of C-band VSAT have been evaluated and then the reflector design is developed with the help of ICARA and MATLAB environment. The proposed design meets the good result of antenna gain and efficiency. The typical gain of prime focus parabolic reflector antenna is 30 dB to 40dB. And the efficiency is 60% to 80% with the good antenna design. By comparing with the typical values, the proposed C-band VSAT antenna design is well optimized with gain of 38dB and efficiency of 78%. In this paper, the better design with compromise gain performance of VSAT receiving parabolic antenna using ICARA software tool and the calculation of C-band downlink path loss is also described. The particular prime focus parabolic reflector antenna is applied for this application and gain of antenna, radiation pattern with far field, near field and the optimized antenna efficiency is also developed. The objective of this paper is to design the downlink receiving antenna of VSAT satellite ground segment with excellent gain and overall antenna efficiency. The filter design analysis is base on Kaiser window method and the simulation results are also presented in this paper. Index Terms: prime focus parabolic reflector antenna, satellite, efficiency, gain, path loss, VSAT. -
Methods for Measuring Rf Radiation Properties of Small Antennas
Helsinki University of Technology Radio Laboratory Publications Teknillisen korkeakoulun Radiolaboratorion julkaisuja Espoo, October, 2001 REPORT S 250 METHODS FOR MEASURING RF RADIATION PROPERTIES OF SMALL ANTENNAS Clemens Icheln Dissertation for the degree of Doctor of Science in Technology to be presented with due permission for public examination and debate in Auditorium S4 at Helsinki University of Technology (Espoo, Finland) on the 16th of November 2001 at 12 o'clock noon. Helsinki University of Technology Department of Electrical and Communications Engineering Radio Laboratory Teknillinen korkeakoulu Sähkö- ja tietoliikennetekniikan osasto Radiolaboratorio Distribution: Helsinki University of Technology Radio Laboratory P.O. Box 3000 FIN-02015 HUT Tel. +358-9-451 2252 Fax. +358-9-451 2152 © Clemens Icheln and Helsinki University of Technology Radio Laboratory ISBN 951-22- 5666-5 ISSN 1456-3835 Otamedia Oy Espoo 2001 2 Preface The work on which this thesis is based was carried out at the Institute of Digital Communications / Radio Laboratory of Helsinki University of Technology. It has been mainly funded by TEKES and the Academy of Finland. I also received financial support from the Wihuri foundation, from HPY:n Tutkimussäätiö, from Tekniikan Edistämissäätiö, and from Nordisk Forskerutdanningsakademi. I would like to thank all these institutions, and the Radio Laboratory, for making this work possible for me. I am especially thankful for the many ideas and helpful guidance that I got from my supervisor professor Pertti Vainikainen during all my work. Of course I would also like to thank the staff of the Radio Laboratory, who provided a pleasant and inspiring working atmosphere, in which I got lots of help from my colleagues - let me mention especially Stina, Tommi, Jani, Lorenz, Eino and Lauri - without whom this work would not have been possible. -
Design and Application of a New Planar Balun
DESIGN AND APPLICATION OF A NEW PLANAR BALUN Younes Mohamed Thesis Prepared for the Degree of MASTER OF SCIENCE UNIVERSITY OF NORTH TEXAS May 2014 APPROVED: Shengli Fu, Major Professor and Interim Chair of the Department of Electrical Engineering Hualiang Zhang, Co-Major Professor Hyoung Soo Kim, Committee Member Costas Tsatsoulis, Dean of the College of Engineering Mark Wardell, Dean of the Toulouse Graduate School Mohamed, Younes. Design and Application of a New Planar Balun. Master of Science (Electrical Engineering), May 2014, 41 pp., 2 tables, 29 figures, references, 21 titles. The baluns are the key components in balanced circuits such balanced mixers, frequency multipliers, push–pull amplifiers, and antennas. Most of these applications have become more integrated which demands the baluns to be in compact size and low cost. In this thesis, a new approach about the design of planar balun is presented where the 4-port symmetrical network with one port terminated by open circuit is first analyzed by using even- and odd-mode excitations. With full design equations, the proposed balun presents perfect balanced output and good input matching and the measurement results make a good agreement with the simulations. Second, Yagi-Uda antenna is also introduced as an entry to fully understand the quasi-Yagi antenna. Both of the antennas have the same design requirements and present the radiation properties. The arrangement of the antenna’s elements and the end-fire radiation property of the antenna have been presented. Finally, the quasi-Yagi antenna is used as an application of the balun where the proposed balun is employed to feed a quasi-Yagi antenna. -
Evaluation of Short-Term Exposure to 2.4 Ghz Radiofrequency Radiation
GMJ.2020;9:e1580 www.gmj.ir Received 2019-04-24 Revised 2019-07-14 Accepted 2019-08-06 Evaluation of Short-Term Exposure to 2.4 GHz Radiofrequency Radiation Emitted from Wi-Fi Routers on the Antimicrobial Susceptibility of Pseudomonas aeruginosa and Staphylococcus aureus Samad Amani 1, Mohammad Taheri 2, Mohammad Mehdi Movahedi 3, 4, Mohammad Mohebi 5, Fatemeh Nouri 6 , Alireza Mehdizadeh3 1 Shiraz University of Medical Sciences, Shiraz, Iran 2 Department of Medical Microbiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran 3 Department of Medical Physics and Medical Engineering, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran 4 Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran 5 School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran 6 Department of Pharmaceutical Biotechnology, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran Abstract Background: Overuse of antibiotics is a cause of bacterial resistance. It is known that electro- magnetic waves emitted from electrical devices can cause changes in biological systems. This study aimed at evaluating the effects of short-term exposure to electromagnetic fields emitted from common Wi-Fi routers on changes in antibiotic sensitivity to opportunistic pathogenic bacteria. Materials and Methods: Standard strains of bacteria were prepared in this study. An- tibiotic susceptibility test, based on the Kirby-Bauer disk diffusion method, was carried out in Mueller-Hinton agar plates. Two different antibiotic susceptibility tests for Staphylococcus au- reus and Pseudomonas aeruginosa were conducted after exposure to 2.4-GHz radiofrequency radiation. The control group was not exposed to radiation. -
Coordinate Transformations-Based Antenna Elements Embedded in a Metamaterial Shell with Scanning Capabilities
electronics Article Coordinate Transformations-Based Antenna Elements Embedded in a Metamaterial Shell with Scanning Capabilities Dipankar Mitra 1,*, Sukrith Dev 2, Monica S. Allen 2, Jeffery W. Allen 2 and Benjamin D. Braaten 1,* 1 Department of Electrical and Computer Engineering, North Dakota State University, Fargo, ND 58105, USA 2 Air Force Research Laboratory, Munitions Directorate, Eglin Air Force Base, FL 32542, USA; [email protected] (S.D.); [email protected] (M.S.A.); [email protected] (J.W.A.) * Correspondence: [email protected] (D.M.); [email protected] (B.D.B.) Abstract: In this work transformation electromagnetics/optics (TE/TO) were employed to realize a non-homogeneous, anisotropic material-embedded beam-steerer using both a single antenna element and an antenna array without phase control circuitry. Initially, through theory and validation with numerical simulations it is shown that beam-steering can be achieved in an arbitrary direction by enclosing a single antenna element within the transformation media. Then, this was followed by an array with fixed voltages and equal phases enclosed by transformation media. This enclosed array was scanned, and the proposed theory was validated through numerical simulations. Further- more, through full-wave simulations it was shown that a horizontal dipole antenna embedded in a metamaterial can be designed such that the horizontal dipole performs identically to a vertical Citation: Mitra, D.; Dev, S.; Allen, dipole in free-space. Similarly, it was also shown that a material-embedded horizontal dipole array M.S.; Allen, J.W.; Braaten, B.D. -
Antenna Theory and Matching
Antenna Theory and Matching Farrukh Inam Applications Engineer LPRF TI 1 Agenda • Antenna Basics • Antenna Parameters • Radio Range and Communication Link • Antenna Matching Example 2 What is an Antenna • Converts guided EM waves from a transmission line to spherical wave in free space or vice versa. • Matches the transmission line impedance to that of free space for maximum radiated power. • An important design consideration is matching the antenna to the transmission line (TL) and the RF source. The quality of match is specified in terms of VSWR or S11. • Standing waves are produced when RF power is not completely delivered to the antenna. In high power RF systems this might even cause arching or discharge in the transmission lines. • Resistive/dielectric losses are also undesirable as they decrease the efficiency of the antenna. 3 When does radiation occur • EM radiation occurs when charge is accelerated or decelerated (time-varying current element). • Stationary charge means zero current ⇒ no radiation. • If charge is moving with a uniform velocity ⇒ no radiation. • If charge is accelerated due to EMF or due to discontinuities, such as termination, bend, curvature ⇒ radiation occurs. 4 Commonly Used Antennas • PCB antennas – No extra cost – Size can be demanding at sub 433 MHz (but we have a good solution!) – Good performance at > 868 MHz • Whip antennas – Expensive solutions for high volume – Good performance – Hard to fit in many applications • Chip antennas – Medium cost – Good performance at 2.4 GHz – OK performance at 868-955 -
Compact Integrated Antennas Designs and Applications for the Mc1321x, Mc1322x, and Mc1323x
Freescale Semiconductor Document Number: AN2731 Application Note Rev. 2, 12/2012 Compact Integrated Antennas Designs and Applications for the MC1321x, MC1322x, and MC1323x 1 Introduction Contents 1 Introduction . 1 With the introduction of many applications into the 2 Antenna Terms . 2 2.4 GHz band for commercial and consumer use, 3 Basic Antenna Theory . 3 Antenna design has become a stumbling point for many 4 Impedance Matching . 5 customers. Moving energy across a substrate by use of an 5 Antennas . 8 RF signal is very different than moving a low frequency 6 Miniaturization Trade-offs . 11 voltage across the same substrate. Therefore, designers 7 Potential Issues . 12 who lack RF expertise can avoid pitfalls by simply 8 Recommended Antenna Designs . 13 following “good” RF practices when doing a board 9 Design Examples . 14 layout for 802.15.4 applications. The design and layout of antennas is an extension of that practice. This application note will provide some of that basic insight on board layout and antenna design to improve our customers’ first pass success. Antenna design is a function of frequency, application, board area, range, and costs. Whether your application requires the absolute minimum costs or minimization of board area or maximum range, it is important to understand the critical parameters so that the proper trade-offs can be chosen. Some of the parameters necessary in selecting the correct antenna are: antenna © Freescale Semiconductor, Inc., 2005, 2006, 2012. All rights reserved. tuning, matching, gain/loss, and required radiation pattern. This note is not an exhaustive inquiry into antenna design. It is instead, focused toward helping our customers understand enough board layout and antenna basics to aid in selecting the correct antenna type for their application as well as avoiding the typical layout mistakes that cause performance issues that lead to delays.