Antenna Patterns and Their Meaning
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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 . -
FOX Hunting Basics FOX Hunting Basics
FOX Hunting Basics FOX Hunting Basics Steps in a transmiter hunt •Signal acquisiton •Triangulaton –Plot bearings on map to get an estmated directon of the transmiter •Homing –“follow your nose” •Snifng –Up close and personal FOX Hunting Basics Following Clues •Finding the transmiter is a process of following clues to the source of the signal. Important clues include: –Directon –Signal Strength –Rate of change in directon –Rate of change in signal strength –Terrain shadowing –Non-radio clues: keep your eyes open! FOX Hunting Basics Tools for Determining Directon •Antenna with directonal patern •Some way to measure signal strength •Some way to reduce signal strength as you get close to avoid receiver overload –“Atenuator” Bearings Bearings Waldo ©DreamWorks Distribution Limited.All rights reserved. Imagery §>2018 Google, Msg data ©2Q1S Google United States Terms Send feel Bearings Equipment Used for DF’ing Equipment Used for DF’ing Equipment Used for DF’ing Radio Attenuator Directional Antenna Equipment Used for DF’ing The attenuator is used to reduce signals so the S meter is in the middle of the scale in the presence of a strong signal Attenuator Strong Signal Equipment Used for DF’ing The attenuator is used to reduce signals so the S meter is in the middle of the scale in the presence of a strong signal Attenuator Strong Signal Equipment Used for DF’ing Time Difference of Arrival TDOA Equipment Used for DF’ing Time Difference of Arrival TDOA How it works •Time Difference of Arrival RDF sets work by switching your receiver between two antennas at a rapid rate. -
Antenna Gain Measurement Using Image Theory
i ANTENNA GAIN MEASUREMENT USING IMAGE THEORY SANDRAWARMAN A/L BALASUNDRAM A project report submitted in partial fulfillment of the requirement for the award of the degree Master of Electrical Engineering Faculty of Electrical and Electronic Engineering Universiti Tun Hussein Onn Malaysia JANUARY 2014 v ABSTRACT This report presents the measurement result of a passive horn antenna gain by only using metallic reflector and vector network analyzer, according to image theory. This method is an alternative way to conventional methods such as the three antennas method and the two antennas method. The gain values are calculated using a simple formula using the distance between the antenna and reflector, operating frequency, S- parameter and speed of light. The antenna is directed towards an absorber and then directed towards the reflector to obtain the S11 parameter using the vector network analyzer. The experiments are performed in three locations which are in the shielding room, anechoic chamber and open space with distances of 0.5m, 1m, 2m, 3m and 4m. The results calculated are compared and analyzed with the manufacture’s data. The calculated data have the best similarities with the manufacturer data at distance of 0.5m for the anechoic chamber with correlation coefficient of 0.93 and at a distance of 1m for the shield room and open space with correlation coefficient of 0.79 and 0.77 but distort at distances of 2m, 3m and 4m at all of the three places. This proves that the single antenna method using image theory needs less space, time and cost to perform it. -
25. Antennas II
25. Antennas II Radiation patterns Beyond the Hertzian dipole - superposition Directivity and antenna gain More complicated antennas Impedance matching Reminder: Hertzian dipole The Hertzian dipole is a linear d << antenna which is much shorter than the free-space wavelength: V(t) Far field: jk0 r j t 00Id e ˆ Er,, t j sin 4 r Radiation resistance: 2 d 2 RZ rad 3 0 2 where Z 000 377 is the impedance of free space. R Radiation efficiency: rad (typically is small because d << ) RRrad Ohmic Radiation patterns Antennas do not radiate power equally in all directions. For a linear dipole, no power is radiated along the antenna’s axis ( = 0). 222 2 I 00Idsin 0 ˆ 330 30 Sr, 22 32 cr 0 300 60 We’ve seen this picture before… 270 90 Such polar plots of far-field power vs. angle 240 120 210 150 are known as ‘radiation patterns’. 180 Note that this picture is only a 2D slice of a 3D pattern. E-plane pattern: the 2D slice displaying the plane which contains the electric field vectors. H-plane pattern: the 2D slice displaying the plane which contains the magnetic field vectors. Radiation patterns – Hertzian dipole z y E-plane radiation pattern y x 3D cutaway view H-plane radiation pattern Beyond the Hertzian dipole: longer antennas All of the results we’ve derived so far apply only in the situation where the antenna is short, i.e., d << . That assumption allowed us to say that the current in the antenna was independent of position along the antenna, depending only on time: I(t) = I0 cos(t) no z dependence! For longer antennas, this is no longer true. -
Chapter 5 the Microstrip Antenna
CHAPTER 5 THE MICROSTRIP ANTENNA 5.1 Introduction Applications that require low-profile, light weight, easily manufactured, inexpensive, conformable antennas often use some form of a microstrip radiator. The microstrip antenna (MSA) is a resonant structure that consists of a dielectric substrate sandwiched between a metallic conducting patch and a ground plane. The MSA is commonly excited using a microstrip edge feed or a coaxial probe. The canonical forms of the MSA are the rectangular and circular patch MSAs. The rectangular patch antenna in Figure 5.1 is fed using a microstrip edge feed and the circular patch antenna is fed using a coaxial probe. (a) (b) Coaxial Feed Microstrip Feed Figure 5.1. (a) A rectangular patch microstrip antenna fed with a microstrip edge feed. (b) A circular patch microstrip antenna fed with a coaxial probe feed. The patch shapes in Figure 5.1 are symmetric and their radiation is easy to model. However, application specific patch shapes are often used to optimize certain aspects of MSA performance. 154 The earliest work on the MSA was performed in the 1950s by Gutton and Baissinot in France and Deschamps in the United States. [1] Demand for low-profile antennas increased in the 1970s, and interest in the MSA was renewed. Notably, Munson obtained the original patent on the MSA, and Howell published the first experimental data involving circular and rectangular patch MSA characteristics. [1] Today the MSA is widely used in practice due to its low profile, light weight, cheap manufacturing costs, and potential conformability. [2] A number of methods are used to model the performance of the MSA. -
Precision Measurement of Antenna System Noise Using Radio Stars
110 IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, VOL. iM-32, NO. 1, MARCH 1983 Precision Measurement of Antenna System Noise Using Radio Stars DAVID F. WAIT Abstract-This paper reviews the National Bureau of Standards a satellite. This satellite signal can be used in a way not too (NBS) preision noise measurements program for antenna systems different than that of a radio star [25]. Finally, a modified gain which have been made using Cassiopeia A and the moon. The Earth comparison technique can be used where one antenna is basi- Terminal Measurement System (ETMS) was developed by NBS to make measurements of figure of merit (GIT), and the noise equivalent cally used to calibrate the strength of some radio source in flux (NEF). The accuracy of the noise measurements are, typically, order to then calibrate a second antenna. between 5 and 15 percent for systems with antenna gains between 51 This paper will discuss only the second method which, if and 65 dB and frequencies between 1 and 10 GHz. applicable, is the most accurate method. It is applicable when Key words-antenna gain; antenna half-power beamwidth; atmo- a) the antenna system can "see" the radio source with a sig- spheric loss; Cassiopeia A; earth terminal measurement system; figure of merit; moon; noise equivalent flux; noise measurement; radio stars; nal-to-noise ratio of better than 0.2, b) the half-power beam- satellite communication. width (HPBW) of the antenna radiation pattern is greater than the diameter of the radio source being used, and c) the antenna I. INTRODUCTION can be pointed at the radio source to a resolution of better than 10 percent of the HPBW. -
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. -
Directional Or Omnidirectional Antenna?
TECHNOTE No. 1 Joe Carr's Radio Tech-Notes Directional or Omnidirectional Antenna? Joseph J. Carr Universal Radio Research 6830 Americana Parkway Reynoldsburg, Ohio 43068 1 Directional or Omnidirectional Antenna? Joseph J. Carr Do you need a directional antenna or an omnidirectional antenna? That question is basic for amateur radio operators, shortwave listeners and scanner operators. The answer is simple: It depends. I would like to give you a simple rule for all situations, but that is not possible. With radio antennas, the "global solution" is rarely the correct solution for all users. In this paper you will find a discussion of the issues involved so that you can make an informed decision on the antenna type that meets most of your needs. But first, let's take a look at what we mean by "directional" and "omnidirectional." Antenna Patterns Radio antennas produce a three dimensional radiation pattern, but for purposes of this discussion we will consider only the azimuthal pattern. This pattern is as seen from a "bird's eye" view above the antenna. In the discussions below we will assume four different signals (A, B, C, D) arriving from different directions. In actual situations, of course, the signals will arrive from any direction, but we need to keep our discussion simplified. Omnidirectional Antennas. The omnidirectional antenna radiates or receives equally well in all directions. It is also called the "non-directional" antenna because it does not favor any particular direction. Figure 1 shows the pattern for an omnidirectional antenna, with the four cardinal signals. This type of pattern is commonly associated with verticals, ground planes and other antenna types in which the radiator element is vertical with respect to the Earth's surface. -
Antenna Characteristics
Antenna Characteristics Team Cygnus Shivam Garg Sheena Agarwal Prince Tiwari Gunjan Bansal Adikeshav C. Outline • Introduction • Characteristics • Methodology • Observations • Inferences Antenna • An antenna is a device designed to radiate and/or receive electromagnetic waves in a prescribed manner. A Yagi Uda antenna meant for home use Schematic diagram of a antenna The current distributions on the antennas produce the radiation. Usually, these current distributions are excited by transmission lines or waveguides. Types Of Antennas Wire Antennas Aperture antennas Micro strip Antennas Reflector antennas Antenna Basics Radiation Pattern • The distribution of radiated energy from an antenna over a surface of constant radius centered upon the antenna as a function of directional angles from antenna . Reciprocity Theorem • The reception pattern of an antenna is identical to its radiation (transmission) pattern. This is a general rule, known as the reciprocity theorem. • A complete radiation pattern is three dimensional function. • a pair of two-dimensional patterns are usually sufficient to characterize the directional properties of an antenna. • In most cases, the two radiation patterns are measured in planes which are perpendicular to each other. • A plane parallel to the electric field is chosen as one plane and the plane parallel to the magnetic field as the other. The two planes are called the E-plane and the H-plane, respectively. 15 E-plane (y-z or θ) and H-plane (x-y or φ) of a Dipole Antenna Gain • Some antennas are highly directional • Directional antenna is an antenna, which radiates (or receives) much more power in (or from) some directions than in (or from) others. -
Antennacraft Hookup
The Antennacraft Mini-State Directional, Rotating Antenna provides excellent reception of VHF/UHF TV channels in most viewing locations. The UV protective housing is made of impact-resistant filled co-polymer, making the exterior resistant to weathering. It features both AC and DC operation and is excellent for use on recreational vehicles 5/5(1). AntennaCraft 5MS RV Home Marine Amplified Antenna OMNIDIRECTIONAL UHF VHF. $ +$ shipping. Make Offer - AntennaCraft 5MS RV Home Marine Amplified Antenna OMNIDIRECTIONAL UHF VHF. Antennacraft HDTV Indoor Ultrathin Amplified Omniidirectional Antenna $ Product Reviews for AntennaCraft High Gain VHF/UHF TV Antenna Pre-Amp (10G) Product reviews help other customers decide which product to purchase, where the best deals are, and your get a sense of what to expect with the product.5/5(4). Manufacturers of TV antennas, amplifiers, and related electronic accessories. Includes product listing, support and contact information. Nov 16, · How to Hook Up a TV Antenna. This wikiHow teaches you how to select and set up an antenna for your TV. Determine your television's antenna connector type. Virtually every TV has an antenna input on the back or side; this is where you'll Views: M. Jun 01, · THE HAPPY SATELLITE NERD EPISODE The Antenna I use! It had 16 position settings it is amplified and works well. I can receive channels from . Related Manuals for Antennacraft Antenna AntennaCraft Mini State 5MS Manual. Amplified uhf/vhf indoor/outdoor tv antenna (8 pages) Antenna AntennaCraft HDX Quick Start Manual. Indoor/outdoor hdtv directional antenna (4 pages) Antenna AntennaCraft . Antennacraft Specification Sheet Model Number:5MS General Channels/Frequency:2 - 69 75 pHYPhysical Maximum Width (in) V ( w/ mast bracket) Turning Radius (in) 22 x 21 x 3 Antenna Performance Average Gain Over Reference Dipole (dB): Low Band: Half-Power Beamwidth. -
Antenna Selection Guide by Richard Wallace
Application Note AN058 Antenna Selection Guide By Richard Wallace Keywords • Antenna Selection • 433 MHz (387 – 510 MHz) Antenna • Anechoic Chamber • 868 MHz (779 – 960 MHz) Antenna • Antenna Parameters • 915 MHz (779 – 960 MHz) Antenna • 169 MHz (136 – 240 MHz) Antenna • 2.4 GHz Antenna • 315 MHz (273 – 348 MHz) Antenna • CC-Antenna-DK 1 Introduction This application note describes important In addition different antenna types are parameters to consider when deciding presented, with their pros and cons. All of what kind of antenna to use in a short the antenna reference designs available range device application. on www.ti.com/lpw are presented including the Antenna Development Kit Important antenna parameters, different [29]. antenna types, design aspects and techniques for characterizing antennas are The last section in this document contains presented. Radiation pattern, gain, references to additional antenna impedance matching, bandwidth, size and resources such as literature, applicable cost are some of the parameters EM simulation tools and a list of antenna discussed in this document. manufacturer and consultants. Antenna theory and practical Correct choice of antenna will improve measurement are also covered. system performance and reduce the cost. Figure 1. Texas Instruments Antenna Development Kit (CC-Antenna-DK) SWRA161B Page 1 of 44 Application Note AN058 Table of Contents KEYWORDS 1 1 INTRODUCTION 1 2 ABBREVIATIONS 3 3 BRIEF ANTENNA THEORY 4 3.1 DIPOLE (Λ/2) ANTENNAS 4 3.2 MONOPOLE (Λ/4) ANTENNAS 5 3.3 WAVELENGTH CALCULATIONS