Introduction to Antennas

Size: px
Start display at page:

Download "Introduction to Antennas"

Transcription

1 Dr. S. X-ol What is an antenna? Introduction to ntennas n antenna is a passive structurethat serves as transition between a transmission lineand airused to transmit and/or receive electromagnetic waves. Dr. Sandra Cruz-ol Electrical and Computer Engineering University of uerto ico at Mayaguez Source Tx eceiver Circuit x ntenna Types of antennas Can be divided into two groups Wireantennas: dipoles, loops, Yagi-Uda pertureantennas: parabolic, horns, microstrip antennas Ulaby, Wire antennas Wire antennas Log periodic Yagi Log periodic Yagi Yagi-Uda with reflector Intro to ntennas 1

2 Dr. S. X-ol perture antennas eflector and yramidal horn antennas Dipole with parabolic and corner reflector Spherical (main reflector) with Gregorian feed Outline ntenna parameters Solid angle, Ω Α and adiation intensity, U adiation pattern, n, sidelobes, HBW Far field zone, r ff Directivity, D or Gain, G ntenna iation impedance, Effective rea, e ll of these parameters are expressed in terms of a transmission antenna, but are identically applicable to a receivingantenna. We ll also study: Friis Transmission Equation adar Equation Spherical coordinates φ azimuth θ elevation x θ90 φ0 z (zenith) φ θ θ0 θ90 φ90 y Solid ngle adiation Intensity Is the power density per solid angle: s 1 r dθ s r sin θ dø s θr arco d s 1 s d r sin θ dø dθ r dω θ ángulo plano dω elemento de ángulo sólido El arco total en un círculo: El área total en una esfera: πr r ngulo total: π [ianes] ngulo sólido total: [ ] [sr] 1 steian (sr) (1 ian) U where r [W/sr] r r ½ e{e H*}rˆ [W/m ] is the power density also known as oynting vector. Intro to ntennas

3 Dr. S. X-ol Total iated power by antenna Can be calculated as; or U dω [W] ds [W] r adiation pattern is the 3D plot of the gain, but usually the D horizontal and verticalcross sections of the iation pattern are considered. efers to the variation of the relative amplitude of the iation as a function of direction. adiation attern Field pattern: E( θ, E n ( θ, E ( θ, ower pattern: ( θ, U ( θ, F n ( θ, ( θ, U ( θ, Where U is the iation intensity to be defined later. Total Solid ngle of an antenna Isotropic antenna Ω ( θ, dω F n [sr] z Ωž It s an hypothetic antenna, i.e., it does not exist in real life, yet it s used as a measuring bar for real antenna characteristics. Is as if you changed the iation pattern beam of an antenna into a pencil beam shape and find out what s the equivalent solid angle occupied by this pattern. atrón n x y It s a point source that occupies a negligible space. Has no directional preference. Its pattern is simply a sphereso it has Ω Ω isotropic [steians]. Ωisotropic (1) dω π π (1)sin θ dθ dφ θ 0 φ 0 adiation attern attern polar plot Whenever we speak of iation patterns, we normally mean we are at a distance far enough from the antenna known as the far field. En _ atrón normalizado - 0 db -3dB -10dB ø HBW HBW atrón de Campo (Escala lineal) atrón de campo o de potencia (Escala logarítmica) COODENDS ECTNGULES Note that when plotted in decibels, the power and field patterns look exactly the same. n 1 Lóbulo principal HBW ("Mainlobe").5 NNBW } Lóbulos menores TON TIICO (Coordenadas polares esféricas, dimensiones) Intro to ntennas 3

4 Dr. S. X-ol Dipole antenna pattern Sidelobes ntennas sometimes show side lobesin the iation pattern. Side lobes are peaks in gain other than the main lobe (the "beam"). Side lobes have bad impact to the antenna quality whenever the system is being used to determine the directionof a signal, for example in Dsystems. Note the iation pattern is donut shaped. Sidelobes of dipole arrays ntenna attern with sidelobes sidelobe Many applications require sidelobe levels (SLL) to be below -0dB. Gain or Directivity Directivity and Gain ll practical antennas iate more than the isotropic antenna in some directions and less in others. Gain is inherently directional; the gain of an antenna is usually measured in the direction which it iates best. n isotropic antenna and a practical antenna fed with the same power. Their patterns would compare as in the figure on the right. D D ( θ, U / If lossless antenna, GD ave /U ave Intro to ntennas 4

5 Dr. S. X-ol Gain or Directivity Gain is measured by comparing an antenna to a model antenna, typically the isotropic antennawhich iates equally in all directions. ( θ, r ( θ, D( θ, / VE 1 d U Do / Ω Ω isotropic / Ω Directivity For an antenna with a single main lobe pointing in the z- direction, Ω can be approximated to the product of the HBW Ω β β then xz yz The Directivity: π D 4 / Ω β β xz yz Far field The distance at which the fields transmitted by an antenna (spherical) can be approximated to plane waves. It s defined as r ff D / λ D is the largest physical dimension of the antenna λ wavelength of operation r ff distance from the antenna to the observation point Beamwidth, HBW Is the distance in ians o degrees between the direction of the iation pattern where the iated power is half of the imum. Can be found by solving F n (θ,.5 10 log log for "pencil beam" shape; HBM 70-3 db o λ -3 db D ntenna Impedance n antenna is seen" by the generator as a load with impedance Z, connected to the line. Z Z ( + L ) + jx The real part is the iation resistance plus the ohmic resistance. Minimizing impedance differences at each interface will reduce SWand imize power transfer through each part of the antenna system. Compleximpedance, Z,of an antenna is related to the electrical length of the antenna at the wavelength in use. The impedance of an antenna can be matched to the feed line and io by adjusting the impedance of the feed line, using the feed line as an impedance transformer. More commonly, the impedance is adjusted at the load (see below) with an antenna tuner, a balun, a matching transformer, matching networks composed of inductorsand capacitors, or matching sections such as the gamma match. ntenna efficiency, η Efficiencyis the ratio of power put into the antenna terminals to the power actually iated adiation in an antenna is caused by iation resistancewhich can only be measured as part of total resistanceincluding loss resistance. η in G η D Intro to ntennas 5

6 Dr. S. X-ol adiation esistance The antenna is connected to a T.L., and it sees it as an impedance. The power iated is The loss power is loss 1 1 I o I o L adar equation What is a ar? eceived power by a ar is ( ) o λo τ σ 3 4 G t r e Where σis the backscattering coefficient of the target [m ] η + loss + loss LICTIONS pplication to several research projects: CS, NS-F, NS-TCESS Show results from undergs working in NS and NSF projects elation to G students ntenna polarization The polarization of an antenna is the polarization of the signals it emits. The ionosphere changes the polarization of signals unpredictably, so for signals which will be reflected by the ionosphere, polarization is not crucial. However, for line-of-sight communications, it can make a tremendous difference in signal quality to have the transmitter and receiver using the same polarization. olarizations commonly considered are vertical, horizontal, and circular. ntenna Bandwidth The bandwidth of an antenna is the range of frequencies over which it is effective, usually centered around the operating or resonant frequency. The bandwidth of an antenna may be increased by several techniques, including using thicker wires, replacing wires with cages to simulate a thicker wire, tapering antenna components (like in a feed horn), and combining multiple antennas into a single assembly and allowing the natural impedance to select the correct antenna. Effective rea How a x antenna extracts energy from incident wave and delivers it to a load? rec D e inc bove is valid for any antenna under matchedload conditions λ Intro to ntennas 6

7 Dr. S. X-ol Friis Transmission Eq. Example In any communication link, there is a transmitting antenna and a receiver with a receiver antenna. adar and Friis TX isotr t tx Gt isotr G tt λ t t rec rt rec λ t r t G tg rt λ ( ) X ntenna rrays Uses many antennas synchronized with each other to increase attern multiplication Example Determine the direction of imum iation, pattern solid angle, directivity and HBW in the y-zplane for an antenna with normalized iation intensity given by cos θ F( θ, 0 π for 0 θ elsewhere and 0 φ π Intro to ntennas 7

Introduction to Antenna principles

Introduction to Antenna principles What is an antenna? Intoduction to ntenna pinciples n antenna is a passive stuctue that seves as tansition between a tansmission line and ai used to tansmit and/o eceive electomagnetic waves. D. Sanda

More information

An Introduction to Antennas

An Introduction to Antennas May 11, 010 An Introduction to Antennas 1 Outline Antenna definition Main parameters of an antenna Types of antennas Antenna radiation (oynting vector) Radiation pattern Far-field distance, directivity,

More information

RADAR Antennas R A D A R R A D A R S Y S T E M S S Y S T E M S. Lecture DR Sanjeev Kumar Mishra. 2 max

RADAR Antennas R A D A R R A D A R S Y S T E M S S Y S T E M S. Lecture DR Sanjeev Kumar Mishra. 2 max Y T E M Y T E M anjeev Kumar Mishra Lecture 17-20 ntennas i p r t t ne L L L N kt BF PG 1 0 3 2 max 4 ) / ( 4 2 Y T E M ntenna: n antenna is an electromagnetic radiator, a sensor, a transducer and an impedance

More information

Half-Wave Dipole. Radiation Resistance. Antenna Efficiency

Half-Wave Dipole. Radiation Resistance. Antenna Efficiency Antennas Simple Antennas Isotropic radiator is the simplest antenna mathematically Radiates all the power supplied to it, equally in all directions Theoretical only, can t be built Useful as a reference:

More information

Topic 3. Fundamental Parameters of Antennas. Tamer Abuelfadl

Topic 3. Fundamental Parameters of Antennas. Tamer Abuelfadl Topic 3 Fundamental Parameters of Antennas Tamer Abuelfadl Electronics and Electrical Communications Department Faculty of Engineering Cairo University Tamer Abuelfadl (EEC, Cairo University) Topic 3 ELC

More information

Notes 21 Introduction to Antennas

Notes 21 Introduction to Antennas ECE 3317 Applied Electromagnetic Waves Prof. David R. Jackson Fall 018 Notes 1 Introduction to Antennas 1 Introduction to Antennas Antennas An antenna is a device that is used to transmit and/or receive

More information

UNIT Explain the radiation from two-wire. Ans: Radiation from Two wire

UNIT Explain the radiation from two-wire. Ans:   Radiation from Two wire UNIT 1 1. Explain the radiation from two-wire. Radiation from Two wire Figure1.1.1 shows a voltage source connected two-wire transmission line which is further connected to an antenna. An electric field

More information

Antenna Fundamentals Basics antenna theory and concepts

Antenna Fundamentals Basics antenna theory and concepts Antenna Fundamentals Basics antenna theory and concepts M. Haridim Brno University of Technology, Brno February 2017 1 Topics What is antenna Antenna types Antenna parameters: radiation pattern, directivity,

More information

EC ANTENNA AND WAVE PROPAGATION

EC ANTENNA AND WAVE PROPAGATION EC6602 - ANTENNA AND WAVE PROPAGATION FUNDAMENTALS PART-B QUESTION BANK UNIT 1 1. Define the following parameters w.r.t antenna: i. Radiation resistance. ii. Beam area. iii. Radiation intensity. iv. Directivity.

More information

Antenna Theory. Introduction

Antenna Theory. Introduction 1 Introduction Antenna Theory Antennas are device that designed to radiate electromagnetic energy efficiently in a prescribed manner. It is the current distributions on the antennas that produce the radiation.

More information

Antenna Engineering Lecture 3: Basic Antenna Parameters

Antenna Engineering Lecture 3: Basic Antenna Parameters Antenna Engineering Lecture 3: Basic Antenna Parameters ELC 405a Fall 2011 Department of Electronics and Communications Engineering Faculty of Engineering Cairo University 2 Outline 1 Radiation Pattern

More information

Resonant Antennas: Wires and Patches

Resonant Antennas: Wires and Patches Resonant Antennas: Wires and Patches Dipole Antennas Antenna 48 Current distribution approximation Un-normalized pattern: and Antenna 49 Radiating power: For half-wave dipole and,, or at exact resonance.

More information

ANTENNA THEORY. Analysis and Design. CONSTANTINE A. BALANIS Arizona State University. JOHN WILEY & SONS New York Chichester Brisbane Toronto Singapore

ANTENNA THEORY. Analysis and Design. CONSTANTINE A. BALANIS Arizona State University. JOHN WILEY & SONS New York Chichester Brisbane Toronto Singapore ANTENNA THEORY Analysis and Design CONSTANTINE A. BALANIS Arizona State University JOHN WILEY & SONS New York Chichester Brisbane Toronto Singapore Contents Preface xv Chapter 1 Antennas 1 1.1 Introduction

More information

Antenna Parameters. Ranga Rodrigo. University of Moratuwa. December 15, 2008

Antenna Parameters. Ranga Rodrigo. University of Moratuwa. December 15, 2008 Antenna Parameters Ranga Rodrigo University of Moratuwa December 15, 2008 Ranga Rodrigo (University of Moratuwa) Antenna Parameters December 15, 2008 1 / 47 Summary of Last Week s Lecture 90 o Radiation

More information

( ) 2 ( ) 3 ( ) + 1. cos! t " R / v p 1 ) H =! ˆ" I #l ' $ 2 ' 2 (18.20) * + ! ˆ& "I #l ' $ 2 ' , ( βr << 1. "l ' E! ˆR I 0"l ' cos& + ˆ& 0

( ) 2 ( ) 3 ( ) + 1. cos! t  R / v p 1 ) H =! ˆ I #l ' $ 2 ' 2 (18.20) * + ! ˆ& I #l ' $ 2 ' , ( βr << 1. l ' E! ˆR I 0l ' cos& + ˆ& 0 Summary Chapter 8. This last chapter treats the problem of antennas and radiation from antennas. We start with the elemental electric dipole and introduce the idea of retardation of potentials and fields

More information

11/8/2007 Antenna Pattern notes 1/1

11/8/2007 Antenna Pattern notes 1/1 11/8/27 ntenna Pattern notes 1/1 C. ntenna Pattern Radiation Intensity is dependent on both the antenna and the radiated power. We can normalize the Radiation Intensity function to construct a result that

More information

ANTENNAS AND WAVE PROPAGATION EC602

ANTENNAS AND WAVE PROPAGATION EC602 ANTENNAS AND WAVE PROPAGATION EC602 B.Tech Electronics & Communication Engineering, Semester VI INSTITUTE OF TECHNOLOGY NIRMA UNIVERSITY 1 Lesson Planning (L-3,P-2,C-4) Chapter No. Name Hours 1. Basic

More information

CHAPTER 5 THEORY AND TYPES OF ANTENNAS. 5.1 Introduction

CHAPTER 5 THEORY AND TYPES OF ANTENNAS. 5.1 Introduction CHAPTER 5 THEORY AND TYPES OF ANTENNAS 5.1 Introduction Antenna is an integral part of wireless communication systems, considered as an interface between transmission line and free space [16]. Antenna

More information

Travelling Wave, Broadband, and Frequency Independent Antennas. EE-4382/ Antenna Engineering

Travelling Wave, Broadband, and Frequency Independent Antennas. EE-4382/ Antenna Engineering Travelling Wave, Broadband, and Frequency Independent Antennas EE-4382/5306 - Antenna Engineering Outline Traveling Wave Antennas Introduction Traveling Wave Antennas: Long Wire, V Antenna, Rhombic Antenna

More information

Antenna & Propagation. Antenna Parameters

Antenna & Propagation. Antenna Parameters For updated version, please click on http://ocw.ump.edu.my Antenna & Propagation Antenna Parameters by Nor Hadzfizah Binti Mohd Radi Faculty of Electric & Electronics Engineering hadzfizah@ump.edu.my Chapter

More information

Dr. John S. Seybold. November 9, IEEE Melbourne COM/SP AP/MTT Chapters

Dr. John S. Seybold. November 9, IEEE Melbourne COM/SP AP/MTT Chapters Antennas Dr. John S. Seybold November 9, 004 IEEE Melbourne COM/SP AP/MTT Chapters Introduction The antenna is the air interface of a communication system An antenna is an electrical conductor or system

More information

Chapter 2. Fundamental Properties of Antennas. ECE 5318/6352 Antenna Engineering Dr. Stuart Long

Chapter 2. Fundamental Properties of Antennas. ECE 5318/6352 Antenna Engineering Dr. Stuart Long Chapter Fundamental Properties of Antennas ECE 5318/635 Antenna Engineering Dr. Stuart Long 1 IEEE Standards Definition of Terms for Antennas IEEE Standard 145-1983 IEEE Transactions on Antennas and Propagation

More information

Antenna Fundamentals. Microwave Engineering EE 172. Dr. Ray Kwok

Antenna Fundamentals. Microwave Engineering EE 172. Dr. Ray Kwok Antenna Fundamentals Microwave Engineering EE 172 Dr. Ray Kwok Reference Antenna Theory and Design Warran Stutzman, Gary Thiele, Wiley & Sons (1981) Microstrip Antennas Bahl & Bhartia, Artech House (1980)

More information

Introduction Antenna Ranges Radiation Patterns Gain Measurements Directivity Measurements Impedance Measurements Polarization Measurements Scale

Introduction Antenna Ranges Radiation Patterns Gain Measurements Directivity Measurements Impedance Measurements Polarization Measurements Scale Chapter 17 : Antenna Measurement Introduction Antenna Ranges Radiation Patterns Gain Measurements Directivity Measurements Impedance Measurements Polarization Measurements Scale Model Measurements 1 Introduction

More information

ELEC 425 Interference Control in Electronics Lecture 7(a) Introduction to Antennas: Terminology

ELEC 425 Interference Control in Electronics Lecture 7(a) Introduction to Antennas: Terminology Dr. Gregory J. Mazzaro Fall 017 ELEC 45 Interference Control in Electronics Lecture 7(a) Introduction to Antennas: Terminology Chapter 9 THE CITADEL, THE MILITARY COLLEGE OF SOUTH CAROLINA 171 Moultrie

More information

BHARATHIDASAN ENGINEERING COLLEGE NATTARAMPALLI Frequently Asked Questions (FAQ) Unit 1

BHARATHIDASAN ENGINEERING COLLEGE NATTARAMPALLI Frequently Asked Questions (FAQ) Unit 1 BHARATHIDASAN ENGINEERING COLLEGE NATTARAMPALLI 635854 Frequently Asked Questions (FAQ) Unit 1 Degree / Branch : B.E / ECE Sem / Year : 3 rd / 6 th Sub Name : Antennas & Wave Propagation Sub Code : EC6602

More information

CHAPTER 8 ANTENNAS 1

CHAPTER 8 ANTENNAS 1 CHAPTER 8 ANTENNAS 1 2 Antennas A good antenna works A bad antenna is a waste of time & money Antenna systems can be very inexpensive and simple They can also be very expensive 3 Antenna Considerations

More information

HHTEHHH THEORY ANALYSIS AND DESIGN. CONSTANTINE A. BALANIS Arizona State University

HHTEHHH THEORY ANALYSIS AND DESIGN. CONSTANTINE A. BALANIS Arizona State University HHTEHHH THEORY ANALYSIS AND DESIGN CONSTANTINE A. BALANIS Arizona State University JOHN WILEY & SONS, INC. New York Chichester Brisbane Toronto Singapore Contents Preface V CHAPTER 1 ANTENNAS 1.1 Introduction

More information

Final Examination. 22 April 2013, 9:30 12:00. Examiner: Prof. Sean V. Hum. All non-programmable electronic calculators are allowed.

Final Examination. 22 April 2013, 9:30 12:00. Examiner: Prof. Sean V. Hum. All non-programmable electronic calculators are allowed. UNIVERSITY OF TORONTO FACULTY OF APPLIED SCIENCE AND ENGINEERING The Edward S. Rogers Sr. Department of Electrical and Computer Engineering ECE 422H1S RADIO AND MICROWAVE WIRELESS SYSTEMS Final Examination

More information

Antennas 1. Antennas

Antennas 1. Antennas Antennas Antennas 1! Grading policy. " Weekly Homework 40%. " Midterm Exam 30%. " Project 30%.! Office hour: 3:10 ~ 4:00 pm, Monday.! Textbook: Warren L. Stutzman and Gary A. Thiele, Antenna Theory and

More information

Antennas 101 Don t Be a 0.97 db Weakling! Ward Silver NØAX

Antennas 101 Don t Be a 0.97 db Weakling! Ward Silver NØAX Antennas 101 Don t Be a 0.97 db Weakling! Ward Silver NØAX Overview Antennas 101 2 Overview Basic Antennas: Ground Plane / Dipole How Gain and Nulls are Formed How Phased Arrays Work How Yagis Work (simplified)

More information

ANTENNA INTRODUCTION / BASICS

ANTENNA INTRODUCTION / BASICS ANTENNA INTRODUCTION / BASICS RULES OF THUMB: 1. The Gain of an antenna with losses is given by: 2. Gain of rectangular X-Band Aperture G = 1.4 LW L = length of aperture in cm Where: W = width of aperture

More information

EMG4066:Antennas and Propagation Exp 1:ANTENNAS MMU:FOE. To study the radiation pattern characteristics of various types of antennas.

EMG4066:Antennas and Propagation Exp 1:ANTENNAS MMU:FOE. To study the radiation pattern characteristics of various types of antennas. OBJECTIVES To study the radiation pattern characteristics of various types of antennas. APPARATUS Microwave Source Rotating Antenna Platform Measurement Interface Transmitting Horn Antenna Dipole and Yagi

More information

Broadband Antenna. Broadband Antenna. Chapter 4

Broadband Antenna. Broadband Antenna. Chapter 4 1 Chapter 4 Learning Outcome At the end of this chapter student should able to: To design and evaluate various antenna to meet application requirements for Loops antenna Helix antenna Yagi Uda antenna

More information

Linear Wire Antennas. EE-4382/ Antenna Engineering

Linear Wire Antennas. EE-4382/ Antenna Engineering Linear Wire Antennas EE-438/5306 - Antenna Engineering Outline Introduction Infinitesimal Dipole Small Dipole Finite Length Dipole Half-Wave Dipole Ground Effect Constantine A. Balanis, Antenna Theory:

More information

SI TECHNICAL 2018 UNIT IV QUESTION BANK

SI TECHNICAL 2018 UNIT IV QUESTION BANK SI TECHNICAL 2018 UNIT IV QUESTION BANK 1. In what range of frequencies are most omnidirectional horizontally polarized antennas used? A. VHF, UHF B. VLF, LF C. SH, EHF D. MF, HF 2. If the current ratios

More information

Fundamentals of Antennas. Prof. Ely Levine

Fundamentals of Antennas. Prof. Ely Levine Fundamentals of Antennas Prof. Ely Levine levineel@zahav.net.il 1 Chapter 3 Wire Antennas 2 Types of Antennas 3 Isotropic Antenna Isotropic radiator is the simplest antenna mathematically Radiates all

More information

Radiation resistance

Radiation resistance Radiation esistance Antennas ae designed fo effective adiation of electomagnetic enegy. Equivalent cicuit of an antenna I in R input adiation esistance R Repesents adiated enegy input loss esistance R

More information

UNIT Write short notes on travelling wave antenna? Ans: Travelling Wave Antenna

UNIT Write short notes on travelling wave antenna? Ans:   Travelling Wave Antenna UNIT 4 1. Write short notes on travelling wave antenna? Travelling Wave Antenna Travelling wave or non-resonant or aperiodic antennas are those antennas in which there is no reflected wave i.e., standing

More information

Introduction to Radar Systems. Radar Antennas. MIT Lincoln Laboratory. Radar Antennas - 1 PRH 6/18/02

Introduction to Radar Systems. Radar Antennas. MIT Lincoln Laboratory. Radar Antennas - 1 PRH 6/18/02 Introduction to Radar Systems Radar Antennas Radar Antennas - 1 Disclaimer of Endorsement and Liability The video courseware and accompanying viewgraphs presented on this server were prepared as an account

More information

EEM.Ant. Antennas and Propagation

EEM.Ant. Antennas and Propagation EEM.ant/0304/08pg/Req: None 1/8 UNIVERSITY OF SURREY Department of Electronic Engineering MSc EXAMINATION EEM.Ant Antennas and Propagation Duration: 2 Hours Spring 2003/04 READ THESE INSTRUCTIONS Answer

More information

10 Antenna gain, beam pattern, directivity

10 Antenna gain, beam pattern, directivity 10 Antenna gain, beam pattern, directivity Adipoleantenna(oracloselyrelatedmonopoletobestudiedinLecture 18) is a near perfect radiator for purposes of broadcasting that is, sending waves of equal amplitudes

More information

Antennas & wave Propagation ASSIGNMENT-I

Antennas & wave Propagation ASSIGNMENT-I Shri Vishnu Engineering College for Women :: Bhimavaram Department of Electronics & Communication Engineering Antennas & wave Propagation 1. Define the terms: i. Antenna Aperture ii. Beam Width iii. Aperture

More information

Chapter 6 Broadband Antenna. 1. Loops antenna 2. Heliksantenna 3. Yagi uda antenna

Chapter 6 Broadband Antenna. 1. Loops antenna 2. Heliksantenna 3. Yagi uda antenna Chapter 6 Broadband Antenna 1. Loops antenna 2. Heliksantenna 3. Yagi uda antenna 1 Design A broadband antenna should have acceptable performance (determined by its pattern, gain and/or feed-point impedance)

More information

Traveling Wave Antennas

Traveling Wave Antennas Traveling Wave Antennas Antennas with open-ended wires where the current must go to zero (dipoles, monopoles, etc.) can be characterized as standing wave antennas or resonant antennas. The current on these

More information

EE 529 Remote Sensing Techniques. Radar

EE 529 Remote Sensing Techniques. Radar EE 59 Remote Sensing Techniques Radar Outline Radar Resolution Radar Range Equation Signal-to-Noise Ratio Doppler Frequency Basic function of an active radar Radar RADAR: Radio Detection and Ranging Detection

More information

ENGR1 Antenna Pattern Measurements

ENGR1 Antenna Pattern Measurements ENGR1 Antenna Pattern Measurements November 29, 2006 Instructor: Dr. Milica Marković Office: Riverside Hall 3028 Email: milica@csus.edu Abstract In this lab we will calculate and measure antenna parameters.

More information

RADIATION PATTERNS. The half-power (-3 db) beamwidth is a measure of the directivity of the antenna.

RADIATION PATTERNS. The half-power (-3 db) beamwidth is a measure of the directivity of the antenna. RADIATION PATTERNS The radiation pattern is a graphical depiction of the relative field strength transmitted from or received by the antenna. Antenna radiation patterns are taken at one frequency, one

More information

LE/ESSE Payload Design

LE/ESSE Payload Design LE/ESSE4360 - Payload Design 4.3 Communications Satellite Payload - Hardware Elements Earth, Moon, Mars, and Beyond Dr. Jinjun Shan, Professor of Space Engineering Department of Earth and Space Science

More information

RECOMMENDATION ITU-R BS * LF and MF transmitting antennas characteristics and diagrams **

RECOMMENDATION ITU-R BS * LF and MF transmitting antennas characteristics and diagrams ** Rec. ITU-R BS.1386-1 1 RECOMMENDATION ITU-R BS.1386-1 * LF and MF transmitting antennas characteristics and diagrams ** (Question ITU-R 201/10) (1998-2001) The ITU Radiocommunication Assembly, considering

More information

Rec. ITU-R F RECOMMENDATION ITU-R F *

Rec. ITU-R F RECOMMENDATION ITU-R F * Rec. ITU-R F.162-3 1 RECOMMENDATION ITU-R F.162-3 * Rec. ITU-R F.162-3 USE OF DIRECTIONAL TRANSMITTING ANTENNAS IN THE FIXED SERVICE OPERATING IN BANDS BELOW ABOUT 30 MHz (Question 150/9) (1953-1956-1966-1970-1992)

More information

Aperture Antennas. Reflectors, horns. High Gain Nearly real input impedance. Huygens Principle

Aperture Antennas. Reflectors, horns. High Gain Nearly real input impedance. Huygens Principle Antennas 97 Aperture Antennas Reflectors, horns. High Gain Nearly real input impedance Huygens Principle Each point of a wave front is a secondary source of spherical waves. 97 Antennas 98 Equivalence

More information

What does reciprocity mean

What does reciprocity mean Antennas Definition of antenna: A device for converting electromagnetic radiation in space into electrical currents in conductors or vice-versa. Radio telescopes are antennas Reciprocity says we can treat

More information

ANTENNA INTRODUCTION / BASICS

ANTENNA INTRODUCTION / BASICS Rules of Thumb: 1. The Gain of an antenna with losses is given by: G 0A 8 Where 0 ' Efficiency A ' Physical aperture area 8 ' wavelength ANTENNA INTRODUCTION / BASICS another is:. Gain of rectangular X-Band

More information

Antenna Fundamentals

Antenna Fundamentals HTEL 104 Antenna Fundamentals The antenna is the essential link between free space and the transmitter or receiver. As such, it plays an essential part in determining the characteristics of the complete

More information

DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING SUBJECT NAME:

DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING SUBJECT NAME: Chendu College of Engineering & Technology (Approved by AICTE, New Delhi and Affiliated to Anna University) Zamin Endathur, Madurantakam, Kancheepuram, District 603311. DEPARTMENT OF ELECTRONICS & COMMUNICATION

More information

Impedance and Loop Antennas

Impedance and Loop Antennas Impedance and Loop Antennas Ranga Rodrigo University of Moratuwa January 4, 2009 Ranga Rodrigo (University of Moratuwa) Impedance and Loop Antennas January 4, 2009 1 / 41 Gain Summary of Last Week s Lecture

More information

Antenna Trainer EAN. Technical Teaching Equipment INTRODUCTION

Antenna Trainer EAN.  Technical Teaching Equipment INTRODUCTION Antenna Trainer EAN Technical Teaching Equipment Products Products range Units 3.-Communications INTRODUCTION Antennas are the main element of aerial communications. They are the transition between a transmission

More information

OSCILLATORS AND MIXERS RF Oscillators 605. Crystal Oscillators Microwave Oscillators 613

OSCILLATORS AND MIXERS RF Oscillators 605. Crystal Oscillators Microwave Oscillators 613 xvi 13 Contents OSCILLATORS AND MIXERS 604 13.1 RF Oscillators 605 General Analysis 606 Oscillators Using a Common Emitter BJT 607 Oscillators Using a Common Gate FET 609 Practical Considerations 610 Crystal

More information

You will need the following pieces of equipment to complete this experiment: Wilkinson power divider (3-port board with oval-shaped trace on it)

You will need the following pieces of equipment to complete this experiment: Wilkinson power divider (3-port board with oval-shaped trace on it) UNIVERSITY OF TORONTO FACULTY OF APPLIED SCIENCE AND ENGINEERING The Edward S. Rogers Sr. Department of Electrical and Computer Engineering ECE422H1S: RADIO AND MICROWAVE WIRELESS SYSTEMS EXPERIMENT 1:

More information

2.5.3 Antenna Temperature

2.5.3 Antenna Temperature ECEn 665: Antennas and Propagation for Wireless Communications 36.5.3 Antenna Temperature We now turn to thermal noise received by an antenna. An antenna in a warm environment receives not only a signal

More information

General License Class Chapter 6 - Antennas. Bob KA9BHD Eric K9VIC

General License Class Chapter 6 - Antennas. Bob KA9BHD Eric K9VIC General License Class Chapter 6 - Antennas Bob KA9BHD Eric K9VIC Learning Objectives Teach you enough to get all the antenna questions right during the VE Session Learn a few things from you about antennas

More information

Antenna Theory EELE 5445

Antenna Theory EELE 5445 Antenna Theory EELE 5445 Lecture 6: Dipole Antenna Dr. Mohamed Ouda Electrical Engineering Department Islamic University of Gaza 2013 The dipole and the monopole The dipole and the monopole are arguably

More information

4/29/2012. General Class Element 3 Course Presentation. Ant Antennas as. Subelement G9. 4 Exam Questions, 4 Groups

4/29/2012. General Class Element 3 Course Presentation. Ant Antennas as. Subelement G9. 4 Exam Questions, 4 Groups General Class Element 3 Course Presentation ti ELEMENT 3 SUB ELEMENTS General Licensing Class Subelement G9 Antennas and Feedlines 4 Exam Questions, 4 Groups G1 Commission s Rules G2 Operating Procedures

More information

KULLIYYAH OF ENGINEERING

KULLIYYAH OF ENGINEERING KULLIYYAH OF ENGINEERING DEPARTMENT OF ELECTRICAL & COMPUTER ENGINEERING ANTENNA AND WAVE PROPAGATION LABORATORY (ECE 4103) EXPERIMENT NO 3 RADIATION PATTERN AND GAIN CHARACTERISTICS OF THE DISH (PARABOLIC)

More information

Chapter 6 Antenna Basics. Dipoles, Ground-planes, and Wires Directional Antennas Feed Lines

Chapter 6 Antenna Basics. Dipoles, Ground-planes, and Wires Directional Antennas Feed Lines Chapter 6 Antenna Basics Dipoles, Ground-planes, and Wires Directional Antennas Feed Lines Some General Rules Bigger is better. (Most of the time) Higher is better. (Most of the time) Lower SWR is better.

More information

5/4/2005 Antenna Pattern present 1/1. C. Antenna Pattern

5/4/2005 Antenna Pattern present 1/1. C. Antenna Pattern 5/4/2005 Antenna Pattern present 1/1 C. Antenna Pattern Radiation Intensity is dependent on both the antenna and the radiated power. We can normalize the Radiation Intensity function to construct a result

More information

The magnetic surface current density is defined in terms of the electric field at an aperture as follows: 2E n (6.1)

The magnetic surface current density is defined in terms of the electric field at an aperture as follows: 2E n (6.1) Chapter 6. Aperture antennas Antennas where radiation occurs from an open aperture are called aperture antennas. xamples include slot antennas, open-ended waveguides, rectangular and circular horn antennas,

More information

CHAPTER 2 MICROSTRIP REFLECTARRAY ANTENNA AND PERFORMANCE EVALUATION

CHAPTER 2 MICROSTRIP REFLECTARRAY ANTENNA AND PERFORMANCE EVALUATION 43 CHAPTER 2 MICROSTRIP REFLECTARRAY ANTENNA AND PERFORMANCE EVALUATION 2.1 INTRODUCTION This work begins with design of reflectarrays with conventional patches as unit cells for operation at Ku Band in

More information

Dipole Antennas. Prof. Girish Kumar Electrical Engineering Department, IIT Bombay. (022)

Dipole Antennas. Prof. Girish Kumar Electrical Engineering Department, IIT Bombay. (022) Dipole Antennas Prof. Girish Kumar Electrical Engineering Department, IIT Bombay gkumar@ee.iitb.ac.in (022) 2576 7436 Infinitesimal Dipole An infinitesimally small current element is called the Hertz Dipole

More information

Large Loop Antennas. Special thanks to graduate students of ECSE 593 class, Winter 2007: Yasha Khatamian, Lin Han, Ruiming Chen

Large Loop Antennas. Special thanks to graduate students of ECSE 593 class, Winter 2007: Yasha Khatamian, Lin Han, Ruiming Chen Large Loop Antennas Special thanks to graduate students of ECSE 593 class, Winter 2007: Yasha Khatamian, Lin Han, Ruiming Chen McGill University, ECSE 405 Antennas, Fall 2009, Prof. M. Popovic 1. History

More information

UNIT-3. Ans: Arrays of two point sources with equal amplitude and opposite phase:

UNIT-3. Ans: Arrays of two point sources with equal amplitude and opposite phase: `` UNIT-3 1. Derive the field components and draw the field pattern for two point source with spacing of λ/2 and fed with current of equal n magnitude but out of phase by 180 0? Ans: Arrays of two point

More information

TELE4652 Mobile and Satellite Communication Systems

TELE4652 Mobile and Satellite Communication Systems TELE465 Mobile and Satellite Communication Systems Lecture 3 Antenna Theory A radio antenna, whether transmitting or receiving, is an integral component of any wireless communication system, whether it

More information

RECOMMENDATION ITU-R BS.80-3 * Transmitting antennas in HF broadcasting

RECOMMENDATION ITU-R BS.80-3 * Transmitting antennas in HF broadcasting Rec. ITU-R BS.80-3 1 RECOMMENDATION ITU-R BS.80-3 * Transmitting antennas in HF broadcasting (1951-1978-1986-1990) The ITU Radiocommunication Assembly, considering a) that a directional transmitting antenna

More information

ECEn 665: Antennas and Propagation for Wireless Communications 48. Since the integrand is periodic, we can change the integration limits to

ECEn 665: Antennas and Propagation for Wireless Communications 48. Since the integrand is periodic, we can change the integration limits to ECEn 665: Antennas and Propagation for Wireless Communications 48 3.3 Loop Antenna An electric dipole antenna radiates an electric field that is aligned with the dipole and a magnetic field that radiates

More information

Mathematical models for radiodetermination radar systems antenna patterns for use in interference analyses

Mathematical models for radiodetermination radar systems antenna patterns for use in interference analyses Recommendation ITU-R M.1851-1 (1/18) Mathematical models for radiodetermination radar systems antenna patterns for use in interference analyses M Series Mobile, radiodetermination, amateur and related

More information

ECE 4370: Antenna Engineering TEST 1 (Fall 2011)

ECE 4370: Antenna Engineering TEST 1 (Fall 2011) Name: GTID: ECE 4370: Antenna Engineering TEST 1 (Fall 2011) Please read all instructions before continuing with the test. This is a closed notes, closed book, closed friend, open mind test. On your desk

More information

DUAL-ANTENNA SYSTEM COMPOSED OF PATCH AR- RAY AND PLANAR YAGI ANTENNA FOR ELIMINA- TION OF BLINDNESS IN CELLULAR MOBILE COMMU- NICATIONS

DUAL-ANTENNA SYSTEM COMPOSED OF PATCH AR- RAY AND PLANAR YAGI ANTENNA FOR ELIMINA- TION OF BLINDNESS IN CELLULAR MOBILE COMMU- NICATIONS Progress In Electromagnetics Research C, Vol. 21, 87 97, 2011 DUAL-ANTENNA SYSTEM COMPOSED OF PATCH AR- RAY AND PLANAR YAGI ANTENNA FOR ELIMINA- TION OF BLINDNESS IN CELLULAR MOBILE COMMU- NICATIONS S.-W.

More information

Coupled Sectorial Loop Antenna (CSLA) for Ultra Wideband Applications

Coupled Sectorial Loop Antenna (CSLA) for Ultra Wideband Applications Coupled Sectorial Loop Antenna (CSLA) for Ultra Wideband Applications N. Behdad and K. Sarabandi Presented by Nader Behdad at Antenna Application Symposium, Monticello, IL, Sep 2004 Email: behdad@ieee.org

More information

The first article of this two-part series explores the basic

The first article of this two-part series explores the basic 768CE.qxd jp.1 1 Antenna Pattern Measurement: Concepts and Techniques M ICHAEL D. FOEGELLE As high frequencies become more common, understanding antenna pattern measurement and how to obtain useful measurements

More information

INSTITUTE OF AERONAUTICAL ENGINEERING Dundigal, Hyderabad ELECTRONICS AND COMMUNIACTION ENGINEERING QUESTION BANK

INSTITUTE OF AERONAUTICAL ENGINEERING Dundigal, Hyderabad ELECTRONICS AND COMMUNIACTION ENGINEERING QUESTION BANK INSTITUTE OF AERONAUTICAL ENGINEERING Dundigal, Hyderabad - 500 04 ELECTRONICS AND COMMUNIACTION ENGINEERING QUESTION BANK Course Name : Antennas and Wave Propagation (AWP) Course Code : A50418 Class :

More information

Propagation mechanisms

Propagation mechanisms RADIO SYSTEMS ETIN15 Lecture no: 2 Propagation mechanisms Ove Edfors, Department of Electrical and Information Technology Ove.Edfors@eit.lth.se Contents Short on db calculations Basics about antennas Propagation

More information

Evangelos Kranakis, School of Computer Science, Carleton University, Ottawa 1. Antennae Basics

Evangelos Kranakis, School of Computer Science, Carleton University, Ottawa 1. Antennae Basics Evangelos Kranakis, School of Computer Science, Carleton University, Ottawa 1 Antennae Basics Evangelos Kranakis, School of Computer Science, Carleton University, Ottawa 2 Essentials Antennae Examples

More information

A LABORATORY COURSE ON ANTENNA MEASUREMENT

A LABORATORY COURSE ON ANTENNA MEASUREMENT A LABORATORY COURSE ON ANTENNA MEASUREMENT Samuel Parker Raytheon Systems Company, 2000 East Imperial Highway RE/R02/V509, El Segundo, CA 90245 Dean Arakaki Electrical Engineering Department, California

More information

RECOMMENDATION ITU-R S.733-1* (Question ITU-R 42/4 (1990))**

RECOMMENDATION ITU-R S.733-1* (Question ITU-R 42/4 (1990))** Rec. ITU-R S.733-1 1 RECOMMENDATION ITU-R S.733-1* DETERMINATION OF THE G/T RATIO FOR EARTH STATIONS OPERATING IN THE FIXED-SATELLITE SERVICE (Question ITU-R 42/4 (1990))** Rec. ITU-R S.733-1 (1992-1993)

More information

UNIVERSITI MALAYSIA PERLIS

UNIVERSITI MALAYSIA PERLIS UNIVERSITI MALAYSIA PERLIS SCHOOL OF COMPUTER & COMMUNICATIONS ENGINEERING EKT 341 LABORATORY MODULE LAB 2 Antenna Characteristic 1 Measurement of Radiation Pattern, Gain, VSWR, input impedance and reflection

More information

S.R.M. Institute of Science & Technology Deemed University School of Electronics & Communication Engineering

S.R.M. Institute of Science & Technology Deemed University School of Electronics & Communication Engineering S.R.M. Institute of Science & Technology Deemed University School of Electronics & Communication Engineering Question Bank Subject Code : EC401 Subject Name : Antennas and Wave Propagation Year & Sem :

More information

It is clear in Figures a and b that in some very specific directions there are zeros, or nulls, in the pattern indicating no radiation.

It is clear in Figures a and b that in some very specific directions there are zeros, or nulls, in the pattern indicating no radiation. Unit 2 - Point Sources and Arrays Radiation pattern: The radiation pattern of antenna is a representation (pictorial or mathematical) of the distribution of the power out-flowing (radiated) from the antenna

More information

A Simple Introduction to Antennas

A Simple Introduction to Antennas Appendix A A Simple Introduction to Antennas A.1 Introduction: Radiation Resistance and Radiation Patterns An antenna is a transitional device, or transducer, that forms an interface for energy traveling

More information

Dhayalini Ramamoorthy. January Master s Thesis in Electronics

Dhayalini Ramamoorthy. January Master s Thesis in Electronics FACULTY OF ENGINEERING AND SUSTAINABLE DEVELOPMENT. Impact of Mutual Coupling among Antenna Arrays on the Performance of the Multipath Simulator System Dhayalini Ramamoorthy January 2014 Master s Thesis

More information

Chapter 4 The RF Link

Chapter 4 The RF Link Chapter 4 The RF Link The fundamental elements of the communications satellite Radio Frequency (RF) or free space link are introduced. Basic transmission parameters, such as Antenna gain, Beamwidth, Free-space

More information

ANTENNAS 101 An Introduction to Antennas for Ham Radio. Lee KD4RE

ANTENNAS 101 An Introduction to Antennas for Ham Radio. Lee KD4RE ANTENNAS 101 An Introduction to Antennas for Ham Radio Lee KD4RE Prepared for Presentation at the Vienna Wireless Society, 13 January 2017 So What is an Antenna Anyway? We are all familiar with wire antennas

More information

Antenna Theory. Wire Antennas

Antenna Theory. Wire Antennas Antenna Theory Wire Antennas Monopole Antenna Long Wire or Traveling wave Antennas Yagi Uda Antenna Prof. D. Kannadassan Reference: C. A. Balanis, J.D. Krauss Monopole antenna Image theory, an intro A

More information

The Basics of Patch Antennas, Updated

The Basics of Patch Antennas, Updated The Basics of Patch Antennas, Updated By D. Orban and G.J.K. Moernaut, Orban Microwave Products www.orbanmicrowave.com Introduction This article introduces the basic concepts of patch antennas. We use

More information

ANTENNA TUTORIAL 1. INTRODUCTION 2. CLASSIFICATION OF ANTENNAS

ANTENNA TUTORIAL 1. INTRODUCTION 2. CLASSIFICATION OF ANTENNAS ANTENNA TUTORIAL Phumzile Malindi, Department of Electrical Engineering, Walter Sisulu University, 19 Manchester Road, Chiselhurst, EAST LONDON, 501, South Africa pmalindi@webmail.co.za 1. INTRODUCTION

More information

VALLIAMMAI ENGINEERING COLLEGE SRM Nagar, Kattankulathur 603 203. DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING QUESTION BANK SUBJECT : EC6602 ANTENNA AND WAVE PROPOGATION SEM / YEAR : VI / III

More information

Unit 4. Antenna Theory

Unit 4. Antenna Theory Unit 4. Antenna Theory A person, who needs to convey a thought, an idea or a doubt, can do so by voice communication. The following illustration shows two individuals communicating with each other. Here,

More information

YAGI-UDA DESIGN OF U.H.F BAND AERIAL TO SUIT LOCAL TV STATIONS

YAGI-UDA DESIGN OF U.H.F BAND AERIAL TO SUIT LOCAL TV STATIONS YAGI-UDA DESIGN OF U.H.F BAND AERIAL TO SUIT LOCAL TV STATIONS PROJECT INDEX: PRJ 079 Presented By: GITAU SIMON WAWERU F17/8261/2004 Supervisor: Mr. S.L OGABA Examiner: Mr. OMBURA Objective The main objective

More information

LECTURE 4: Fundamental Antenna Parameters 1. Radiation Pattern Note:

LECTURE 4: Fundamental Antenna Parameters 1. Radiation Pattern Note: LECTURE 4: Fundamental Antenna Parameters (Radiation pattern. Pattern beamwidths. Radiation intensity. Directivity. Gain. Antenna efficiency and radiation efficiency. Frequency bandwidth. Input impedance

More information

Newsletter 3.1. Antenna Magus version 3.1 released! New antennas in the database. Square pin-fed septum horn. July 2011

Newsletter 3.1. Antenna Magus version 3.1 released! New antennas in the database. Square pin-fed septum horn. July 2011 Newsletter 3.1 July 2011 Antenna Magus version 3.1 released! Antenna Magus 3.0 was such a feature laden release that not all of the new features could be mentioned in the newsletter, so we decided to rather

More information