GENERAL CLASS Amateur Radio License Exam
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Coplanar Stripline-Fed Wideband Yagi Dipole Antenna with Filtering-Radiating Performance
electronics Article Coplanar Stripline-Fed Wideband Yagi Dipole Antenna with Filtering-Radiating Performance Yong Chen 1, Gege Lu 2, Shiyan Wang 2 and Jianpeng Wang 2,* 1 School of Physics and Electronic Electrical Engineering, Huaiyin Normal University, Huaian 223300, China; [email protected] 2 Ministerial Key Laboratory of JGMT, Nanjing University of Science and Technology, Nanjing 210094, China; [email protected] (G.L.); [email protected] (S.W.) * Correspondence: [email protected] Received: 6 July 2020; Accepted: 4 August 2020; Published: 6 August 2020 Abstract: In this article, a wideband filtering-radiating Yagi dipole antenna with the coplanar stripline (CPS) excitation form is investigated, designed, and fabricated. By introducing an open-circuited half-wavelength resonator between the CPS structure and dipole, the gain selectivity has been improved and the operating bandwidth is simultaneously enhanced. Then, the intrinsic filtering-radiating performance of Yagi antenna is studied. By implementing a reflector on initial structure, it is observed that two radiation nulls appear at both lower and upper gain passband edges, respectively. Moreover, in order to improve the selectivity in the upper stopband, a pair of U-shaped resonators are employed and coupled to CPS directly. As such, the antenna design is finally completed with expected characteristics. To verify the feasibility of the proposed scheme, a filtering Yagi antenna prototype with a wide bandwidth covering from 3.64 GHz to 4.38 GHz is designed, fabricated, and measured. Both simulated and measured results are found to be in good agreement, thus demonstrating that the presented antenna has the performances of high frequency selectivity and stable in-band gain. -
Corrugated Feed-Horn Arrays for Future CMB Polarization Experiments Settore Scientifico Disciplinare FIS/01
UNIVERSITA` DEGLI STUDI DI MILANO FACOLTA` DI SCIENZE MATEMATICHE, FISICHE E NATURALI DOTTORATO DI RICERCA IN FISICA, ASTROFISICA E FISICA APPLICATA Corrugated feed-horn arrays for future CMB polarization experiments Settore Scientifico disciplinare FIS/01 Coordinatore: Prof. Marco BERSANELLI Tutore: Prof. Marco BERSANELLI Co-Tutore: Dott. Fabrizio VILLA Tesi di dottorato di: Francesco DEL TORTO Ciclo XXIV Anno Accademico 2011-2012 To my parents Introduction The actual most corroborated model of modern cosmology is the “Hot Big Bang Model”, that results in agree with the cosmological scientific discov- eries of the last 50 years. The main observational pillars that support the model are: the discovery by Edwin Hubble of the expansion of the Universe, the abundances of the primordial elements and the discovery of the Cosmic Microwave Background (CMB) radiation. In 1929 Edwin Hubble discovered the linear relationship in distant galax- ies between their distance and recession velocity: v = Hd. The current value for the Hubble constant is known with very high precision as 72 8 Km/sec/Mpc [1], from the measurements obtained by the Hubble Space Tele-± scope on even far distant galaxies w.r.t. to the Hubble measurements. According to the Hot Big Bang Model, in the first era of its life, the Universe was constituted by photons, electrons and protons. During this time the firsts primordial elements were produced, i.e. Helium, Deuterium, and Beryllium. The abundances of the primordial elements can be calculated with precision by the Hot Big Bang Model, resulting in good agreement with the measured abundances [2], [3]. In 1965 Arno Penzias and Robert Wilson discovered the CMB, already predicted in 1948 by George Gamow in the framework of an Hot Big Bang Model. -
Radiation Pattern of Yagi-Uda Antenna Using Usrp on Gnu Radio Platform
IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 RADIATION PATTERN OF YAGI-UDA ANTENNA USING USRP ON GNU RADIO PLATFORM Sreethivya1 M, Dhanya.M.G2, Nimisha.C3, Gandhiraj.R4, Soman.K.P5 1M.Tech Student, Department of CEN, Amrita Vishwa Vidyapeetham, Tamilnadu, India 2M.Tech Student, Department of CEN, Amrita Vishwa Vidyapeetham, Tamilnadu, India 3M.Tech Student, Department of CEN, Amrita Vishwa Vidyapeetham, Tamilnadu, India 4Assistant Professor, Department of ECE, Amrita Vishwa Vidyapeetham, Tamilnadu, India 5Head of Department, Department of CEN, Amrita Vishwa Vidyapeetham, Tamilnadu, India Abstract In this paper we are planning to realize radiation pattern of a Unidirectional Yagi-Uda antenna using USRP2 which is connected with GNU Radio. Our basic approach is to get radiation pattern for H-plane structured Yagi-Uda antenna at different angles (0-360). The proposed method is of low cost and easy to implement with two USRP, two PC and a Yagi-Uda antenna. The platform which we have used for getting radiation pattern values is GNU Radio which is open source software.Yagi-Uda antenna is used for long distance communication since it has good directivity. It is designed with three pairs of oscillator, directors and active transducer. Oscillator is connected to the voltage feeder and active transducer incapacitates the wave from different sides of antenna. Keywords: Yagi-Uda antenna, GNU Radio, Radiation pattern, USRP2, Folded Dipole antenna. -----------------------------------------------------------------------***----------------------------------------------------------------------- 1. INTRODUCTION directors a yagi has, greater the forward gain. We have used a single director along with a reflector and a driven element. In this paper we present radiation pattern of a unidirectional Yagi [2] antenna. -
Progress Toward Corrugated Feed Horn Arrays in Silicon Abstract
Progress Toward Corrugated Feed Horn Arrays in Silicon J. Britton,∗ K. W. Yoon, J. A. Beall, D. Becker, H. M. Cho, G. C. Hilton, M. D. Niemack, and K. D. Irwin Quantum Sensors Group, NIST, Boulder, CO 80305, USA Abstract We are developing monolithic arrays of corrugated feed horns fabricated in silicon for dual-polarization single-mode operation at 90, 145 and 220 GHz. The arrays consist of hundreds of platelet feed horns assembled from gold-coated stacks of micro- machined silicon wafers. As a first step, Au-coated Si waveguides with a circular, corrugated cross section were fabricated; their attenuation was measured to be less than 0.15 dB/cm from 80 to 110 GHz at room temperature. To ease the manufacture of horn arrays, electrolytic deposition of Au on degenerate Si without a metal seed layer was demonstrated. An apparatus for measuring the radiation pattern, optical efficiency, and spectral band-pass of prototype horns is described. Feed horn arrays made of silicon may find use in measurements of the polarization anisotropy of the cosmic microwave background radiation. Imaging detectors at millimeter wavelengths can now be built with hundreds of pixels.[1] However, parallel gains in free-space coupling optics have lagged. At NIST we are pursuing monolithic arrays of corru- gated platelet feed horns made with Si. Each layer in the stack is a Si wafer with photolithographically de- fined apertures. Once assembled and coated with Au, these horn arrays are expected to feature the same low loss, wide bandwidth, minimal side lobes and low cross- correlation as electroformed horns.[2, 3] Moreover, rel- ative to metal corrugated arrays [4], Si horn arrays are expected to have the following benefits: (a) a thermal ex- pansion matched to Si detectors, (b) lower thermal mass, and (c) a straightforward development to arrays of thou- sands of horns. -
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. -
Resolving Interference Issues at Satellite Ground Stations
Application Note Resolving Interference Issues at Satellite Ground Stations Introduction RF interference represents the single largest impact to robust satellite operation performance. Interference issues result in significant costs for the satellite operator due to loss of income when the signal is interrupted. Additional costs are also encountered to debug and fix communications problems. These issues also exert a price in terms of reputation for the satellite operator. According to an earlier survey by the Satellite Interference Reduction Group (SIRG), 93% of satellite operator respondents suffer from satellite interference at least once a year. More than half experience interference at least once per month, while 17% see interference continuously in their day-to-day operations. Over 500 satellite operators responded to this survey. Satellite Communications Overview Satellite earth stations form the ground segment of satellite communications. They contain one or more satellite antennas tuned to various frequency bands. Satellites are used for telephony, data, backhaul, broadcast, community antenna television (CATV), internet, and other services. Depending on the application, each satellite system may be receive only or constructed for both transmit and receive operations. A typical earth station is shown in figure 1. Figure 1. Satellite Earth Station Each satellite antenna system is composed of the antenna itself (parabola dish) along with various RF components for signal processing. The RF components comprise the satellite feed system. The feed system receives/transmits the signal from the dish to a horn antenna located on the feed network. The location of the receiver feed system can be seen in figure 2. The satellite signal is reflected from the parabolic surface and concentrated at the focus position. -
Development of Conical Horn Feed for Reflector Antenna
International Journal of Engineering and Technology Vol. 1, No. 1, April, 2009 1793-8236 Development of Conical Horn Feed For Reflector Antenna Jagdish. M. Rathod, Member, IACSIT and Y.P.Kosta, Senior Member IEEE waveguide that provides the impedance transformation Abstract—We have designed a antenna feed with prime between the waveguide impedance and the free-space concerned that with the growing conjunctions in the mobile impedance. Horn radiators are used both as antennas in their networks, the parabolic antenna are evolving as an useful device own right, and as illuminators for reflector antennas. Horn for point to point communications where the need for high antennas are not a perfect match to the waveguide, although directivity and high power density is at the prime importance. With these needs we have designed the unusual type of feed standing wave ratios of 1.5:1 or less are achievable. The gain antenna for parabolic dish that is used for both reception and of a horn radiator is proportional to the area A of the flared transmission purpose. This different frequency band open flange), and inversely proportional to the square of the performance having horn feed, works for the parabolic wavelength [8].Following Fig.1 gives types of Horn reflector antenna. We have worked on frequency band between radiators. 4.8 GHz to 5.9 GHz for horn type of feed. Here function of the horn is to produce uniform phase front with a larger aperture than that of the waveguide and hence greater directivity. Parabolic dish antenna is the most commonly and widely used antenna in communication field mainly in satellite and radar communication. -
POWER MICROWAVE FEED HORN C. Chang Department of Engineering
Progress In Electromagnetics Research, PIER 101, 157{171, 2010 DESIGN AND EXPERIMENTS OF THE GW HIGH- POWER MICROWAVE FEED HORN C. Chang Department of Engineering Physics Tsinghua University Beijing, China X. X. Zhu, G. Z. Liu, J. Y. Fang, R. Z. Xiao, C. H. Chen H. Shao, J. W. Li, H. J. Huang, and Q. Y. Zhang Northwest Institute of Nuclear Technology Xi'an, Shannxi, China Z. Q. Zhang National Key Laboratory of Antennas and Microwave Technology Xidian University Xi'an, Shannxi, China Abstract|Design and optimization of high-power microwave (HPM) feed horn by combining the aperture ¯eld with radiation patterns are presented in the paper. The optimized feed horn in C band satis¯es relatively uniform aperture ¯eld, power capacity higher than 3 GW, symmetric radiation patterns, low sidelobes, and compact length. Cold tests and HPM experiments were conducted to investigate the radiation patterns and power capacity of the horn. The theoretical radiation patterns are consistent with the cold test and HPM experimental results. The power capacity of the compact HPM horn has been demonstrated by HPM experiments to be higher than 3 GW. 1. INTRODUCTION The maximum power produced by S-band resonant BWO has attained 5 GW with 100 J energy pulses [1]. With the development of narrowband multi-giga-watt HPM sources operated under vacuum, the power capacity of the HPM horn has become the major factor of Corresponding author: C. Chang ([email protected]). 158 Chang et al. limiting HPM transmission and radiation [2{5]. When the electric ¯eld amplitude at the aperture of the horn is higher than the breakdown threshold, secondary electron multipactor and plasma discharge happen at the vacuum side of the dielectric radome, leading to HPM breakdown and pulse shortening [2{5]. -
PARABOLIC DISH ANTENNAS Paul Wade N1BWT © 1994,1998
Chapter 4 PARABOLIC DISH ANTENNAS Paul Wade N1BWT © 1994,1998 Introduction Parabolic dish antennas can provide extremely high gains at microwave frequencies. A 2- foot dish at 10 GHz can provide more than 30 dB of gain. The gain is only limited by the size of the parabolic reflector; a number of hams have dishes larger than 20 feet, and occasionally a much larger commercial dish is made available for amateur operation, like the 150-foot one at the Algonquin Radio Observatory in Ontario, used by VE3ONT for the 1993 EME Contest. These high gains are only achievable if the antennas are properly implemented, and dishes have more critical dimensions than horns and lenses. I will try to explain the fundamentals using pictures and graphics as an aid to understanding the critical areas and how to deal with them. In addition, a computer program, HDL_ANT is available for the difficult calculations and details, and to draw templates for small dishes in order to check the accuracy of the parabolic surface. Background In September 1993, I finished my 10 GHz transverter at 2 PM on the Saturday of the VHF QSO Party. After a quick checkout, I drove up Mt. Wachusett and worked four grids using a small horn antenna. However, for the 10 GHz Contest the following weekend, I wanted to have a better antenna ready. Several moderate-sized parabolic dish reflectors were available in my garage, but lacked feeds and support structures. I had thought this would be no problem, since lots of people, both amateur and commercial, use dish antennas. -
G9C01 (A) Which of the Following Would Increase the Bandwidth of a Yagi Antenna? A
Section 5.2 G9C01 (A) Which of the following would increase the bandwidth of a Yagi antenna? A. Larger-diameter elements B. Closer element spacing C. Loading coils in series with the element D. Tapered-diameter elements ~~ G9C02 (B) What is the approximate length of the driven element of a Yagi antenna? A. 1/4 wavelength B. 1/2 wavelength C. 3/4 wavelength D. 1 wavelength ~~ G9C03 (A) How do the lengths of a three-element Yagi reflector and director compare to that of the driven element? A. The reflector is longer, and the director is shorter B. The reflector is shorter, and the director is longer C. They are all the same length D. Relative length depends on the frequency of operation ~~ G9C05 (A) How does increasing boom length and adding directors affect a Yagi antenna? A. Gain increases B. Beamwidth increases C. Front-to-back ratio decreases D. Front-to-side ratio decreases ~~ G9C06 (D) What configuration of the loops of a two-element quad antenna must be used for the antenna to operate as a beam antenna, assuming one of the elements is used as a reflector? A. The driven element must be fed with a balun transformer B. There must be an open circuit in the driven element at the point opposite the feed point C. The reflector element must be approximately 5 percent shorter than the driven element D. The reflector element must be approximately 5 percent longer than the driven element ~~ G9C07 (C) What does “front-to-back ratio” mean in reference to a Yagi antenna? A. -
A Concept for Wildlife Tracking Using VHF Radio
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by UTHM Institutional Repository TITLE A CONCEPT FOR WILDLIFE TRACKING USING ULTRA HIGH FREQUENCY (UHF) RADIO MOHD ZAIN BIN ABDUL RAHIM A project report submitted in partial fulfillment of the requirement for the award of the Degree of Master of Electrical Engineering Faculty of Electric & Electronic Engineering Universiti Tun Hussein Onn Malaysia JULY 2014 v ABSTRACT Wildlife tracking technology is a method routinely used in the detection of small animals or big animals. Normally, a radio tracking using a low frequency between 30MHz to 300MHz known as Very High Frequency (VHF). In this study, a band of Ultra High Frequency (UHF) with a frequency 315MHz is used as a transmitter. While a encoder HT12E is used as a function of generate a data signal to the RF Transmitter module 315MHz to transmit. The signal sent by the transmitter detected by Yagi antenna as a receiver and was designed at a frequency of 315MHz with a gain is 10.68dBi. Received power detected by Yagi antenna shown at Anritsu Spectrum Analyzer. The highest differences between power received at vegetation area compared to open area is about 10dBm while the furthest distance of the receiver can be traced in the vegetation area is about 67 meters, and for open area is more than 70 meters. The results of this study agreed with Tamir’model for propagation in forest whereas can be used in a prediction of initial pattern of power received signal which is gradually decrease if a receiver moves away from the transmitter over much larger distances. -
Characteristics of Naval Fire . Control Radar
COPY~ CO NFI oP 1895· CHARACTERISTICS OF ,. NAVAL FIRE .CONTROL RADAR • ~ r' -i8Nfi6ENtiAt• ABUREAU OF ORDNANCE PUBLICATION ~ OP 1895 CHARACTERISTICS OF NAVAL FIRE CONTROL RADAR 12 NOVEMBER 1954 DEPARTMENT OF THE NAVY BUREAU OF ORDNANCE WASHINGTON 25, D. C. 12 November 1954 ORDNANCE PAMPHLET 1895 CHARACTERISTICS OF NAVAL FIRE CONTROL RADAR 1. Ordnance Pamphlet 1895 describes both the fundamental principles of operation of radar equipment in general and the characteristics of specific United States Naval fire control radar equipment. 2. This publication is intended for use by all personnel concerned with radar operation in general, and with the application of basic radar principles to fire control radar. 3. This publication does not supersede any existing publication. 4. This publication is El8N¥'1!HU! AitL and shall be safeguarded in ac cordance with the security provisions of U. S. Navy Regulations. It is for bidden to make extracts from or to copy this classified document, except as provided for in Article 0910 of the United States Navy Security Manual for Classified Matter. M. F. ScHoEFFEL Rear Admiral, U. S. Navy Ohief, Bureau of Ordnance .tONFIDENTIAL- 'i!Qt 'FilEt 'IJ,ll CONTENTS Chapter Page Chapte1· Page FOREWORD vi 2. Close-in Targets ............. 28 (cont) Merging Targets ............. 28 PART I-GENERAL Propeller Modulation ......... 28 1. PRINCIPLES OF THE RADAR ART 1 Geographical and Atmospheric The Echo Principle ............. 1 Conditions ................ 28 The Radio Echo at Work ......... 1 Low-flying Targets ........... 29 Radar Measurements ........... 2 Land Echoes ................ 29 Factors Affecting Radar Radar Countermeasures ...... 31 Measurements ............... 6 Spotting Surface Gun Fire ...... 32 Power and Range ............ 6 Range Spotting .............