right during the VE Session Have fun Bob, KA9BH Eric, K9VIC
|
|
- Ernest Knight
- 5 years ago
- Views:
Transcription
1 Radio Wave Propagation Teach you enough to get all right during the VE Session Learn a few things from you Have fun Finish everything on time (if the propagation questions about your experiences not a little early) Bob, KA9BH Eric, K9VIC
2 Radio Wave Propagation But first some leftovers from last week...
3 The Smith Chart Dr. Zachary Smith
4 The Smith Chart Resistance/conductance component at the center. Zero resistance at left Infinite resistancee at right Reactance arcs above/below the center. Inductive above (+1j Ω at top center) Capacitive below (-1j Ω at bottom center) Standard (normalized) resistance at center of the chart. SWR circles around center.
5 What's it good for? The Smith Chart Used to portray complex impedances graphically Can be used to solve for impedances when transformed through feedlines, etc. Move clockwise around the chart from a load to the source One wavelength is twice around the chart (e.g., ¼ wavelength would be ½ way around the circle) Can be used for the open/shorted feedline questions.
6 The Smith Chart Open/Shorted Feedline Questions: Shorted feedline, 1/8 wavelength long A shorted feedline (at the load) has essentially zero resistance Moving ¼ turn clockwise (toward the source) we arive at +1j Ω, an inductive load viewed from the source. Open feedline, 1/ /4 wavelength long An open feedline (at the load) has essentially an infinite resistance Moving 1/2 turn clockwise (toward the source) we arive at zero Ω, a low impedance load viewed from the source.
7 VE Exam Three Exam questions, one each from three groups: Earth-Moon-Earth (EME) communications; meteor scatter. Transequetorial propagation; long path; gray line; multi-path propagation. Aural propagation; selective fading; radio-path horizon; take-off angle over flat or sloping terrain(covered last session); earth effects on propagation (also covered last session); less common propagation modes.
8 HF Propagation Ground Wave ( meters) 50 miles maximum Polarization dependent Vertical better than horizontal Remember most horizontal antennas have a small vertical componant (next slide) Frequency dependent Lower Frequency better than higher Due to refraction along the earth's
9 Ground Wave HF Propagation
10 Ground Wave HF Propagation
11 HF Propagation Ionosphere
12 HF Propagation Ionosphere
13 HF Propagation Ionosphere
14 Critical Frequency Critical Angle HF Propagation Ionosphere The highest frequency that will be returned to the earth when transmitted vertically under given ionospheric conditions The highest angle with respect to a vertical line at which a radio wave of a specified frequency can be propagated and still returned to the earth from the ionosphere
15 HF Propagation Ionosphere Maximum Usable Frequency (MUF) The upper frequency limit that can be used for transmissions between two points independent of transmitter power.
16 HF Propagation Ionosphere
17 HF Propagation Ionosphere Ionospheric Layer and Height (miles) D Layer E Layer F1 Layer 140 F2 Layer F Layer Maximum Skip Distance (miles) Absorbtive 1,400 Minimal Skip Affect 2,500 2,500
18 Long Path HF Propagation Ionosphere Signal takes the longer of two great circle paths Long path is 180 opposite short path May hear both paths (echo) Works on all HF bands (160 thru 10- meters) Very consistent on 20-meters
19 HF Propagation Ionosphere
20 Sporadic E HF Propagation Ionosphere Applies to VHF (or 10-meters) 50 MHz: miles 144 MHz: 1900 miles Strong cycle May, June, July Lesser cycle December, early January Independent of Solar Cycle
21 Sporadic E HF Propagation Ionosphere When 28 MHz goes short ( miles), 50 MHz goes long (1,400 miles) When 50 MHz shortens (400 miles), 144 MHz goes long (1,400 miles) HF may seem dead as the F-layers are blocked (or the E-layer is the top reflector) Not the same as a Pedersen Ray (F 2 phenomina)
22 HF Propagation NVIS (Near Vertial Incident Skywave)
23 HF Propagation Ionosphere (backscatter)
24 HF Propagation Ionosphere Grayline Propagation Occurs at daytime/nighttime terminator (twilight, sunset, sunrise) D-layer quickly disappears or hasn't yet formed F-layer is present Skip is 8-10,0000 miles on 3 or 4 HF bands Always along Grayline (NOT one station in twilight, the other in darkness or light)
25 HF Propagation Trans-equatorial propagation Best late afternoon/early evening Reflection height suggests bulged F- layer miles over magnetic equator (add frequencies) Why do we care? Chicago to magnetic equator is more than 2500 miles (south of 'real' equator)
26 Selective Fading HF Propagation Phase difference between components of a signal combine and cancel (generally due to multipath) Large bandwidth are more effected Phase band modes (even narrow band) are very succeptible
27 Meteor Scatter Propagation Ionosphere Transmit using 15 second intervals Popular modes: Fast CW (100+ WPM) WSJT JT6 Best during meteor showers, and in the morning (heading into the shower) Can be used any time with JT-modes
28 EME Earth-Moon-Earth Theoretically works for any two stations that can both see the moon (12,000 miles) Frequencies Used: Transmit 'schedule' 2-meters: 2 minutes on, 2 minutes listening 70-cm: 2.5 minutes on, 2.5 minutes listening
29 EME Considerations Distance (2-week cycle) Perigee (closest to earth) = 359,000 km Apogee (farthest from earth) = 404,510 km Why do we care, they're both pretty far? Apogee is about X perigee Signal increase is (1.127) 2 =1.270 (~30%) DB = 10 log 1.3/1 = 1.14 db
30 EME Considerations Moon's orbit is eliptical and tilted re: earth Velocity not constant relative to earth Allows 59% of the moon to be seen 41% of the far side (not dark) never seen Libration Fading Fluttery, irregular fading
31 Considerations EME How do we increase s+n/n? Bandwidth (cw, WSJT, JT65, etc.) ERP (amps, lots of aluminum) Rx noise level (low noise rx a must)
32 VHF/UHFPropagation Troposhperic Ducting Troposphere 0 6 miles in height Ducting products potential contacts of 500 miles Due to radio horizon Horizon =( (2h) 1/2 h = haat horizon in miles Radio horizon ~15% farther than geometric horizon Six miles = 31,,680 feet, Horizon = miles (double for two stations)
33 VHF/UHF Propagation Aural Propagation Think Aurora Borealis (Australis) Charged particle from the sun create ions E-layer ionization layer SSB rarely readable CW best option (with fluttery tones) Both stations point antennas north (in the northern hemisphere)
34 VHF/UHF Propagation Meteor Scatter Meteor creates 12-mile ion trail at E-layer height Propagation miles Works on 28 to 144 MHz (50 MHz best bet) Short lived: 30 seconds on 50 MHz 3 seconds on 144 MHz <1 second on 432 MHz
35 Radio Wave Propagation Questions?
Topics in Propagation
Topics in Propagation Extra Class Course Spring 2013 Andy Durbin k3wyc Propagation The magic that allows a signal to travel between the transmitting antenna and the receiving antenna. This course is limited
More informationGeneral Classs Chapter 7
General Classs Chapter 7 Radio Wave Propagation Bob KA9BHD Eric K9VIC Learning Objectives Teach you enough to get all the propagation questions right during the VE Session Learn a few things from you about
More information4/18/2012. Supplement T3. 3 Exam Questions, 3 Groups. Amateur Radio Technician Class
Amateur Radio Technician Class Element 2 Course Presentation ti ELEMENT 2 SUB-ELEMENTS Technician Licensing Class Supplement T3 Radio Wave Characteristics 3 Exam Questions, 3 Groups T1 - FCC Rules, descriptions
More information4/29/2012. General Class Element 3 Course Presentation. Radio Wave Propagation. Radio Wave Propagation. Radio Wave Propagation.
General Class Element 3 Course Presentation ti ELEMENT 3 SUB ELEMENTS General Licensing Class Subelement G3 3 Exam Questions, 3 Groups G1 Commission s Rules G2 Operating Procedures G3 G4 Amateur Radio
More informationTechnician License Course Chapter 4
Technician License Course Chapter 4 Propagation, Basic Antennas, Feed lines & SWR K0NK 26 Jan 18 The Antenna System Antenna: Facilitates the sending of your signal to some distant station. Feed line: Connects
More informationAmateur Radio License. Propagation and Antennas
Amateur Radio License Propagation and Antennas Todays Topics Propagation Antennas Propagation Modes Ground wave Low HF and below, ground acts as waveguide Line-of-Sight (LOS) VHF and above, radio waves
More informationAntennas and Propagation Chapters T4, G7, G8 Antenna Fundamentals, More Antenna Types, Feed lines and Measurements, Propagation
Antennas and Propagation Chapters T4, G7, G8 Antenna Fundamentals, More Antenna Types, Feed lines and Measurements, Propagation =============================================================== Antenna Fundamentals
More informationAN INTRODUCTION TO VHF/ UHF PROPAGATION. Paul Wilton, M1CNK
AN INTRODUCTION TO VHF/ UHF PROPAGATION Paul Wilton, M1CNK OVERVIEW Introduction Propagation Basics Propagation Modes Getting Started in 2m DX INTRODUCTION QRV on 2m SSB since Aug 1998, on 6m since Jan
More informationLesson 12: Signal Propagation
Lesson 12: Signal Propagation Preparation for Amateur Radio Technician Class Exam Topics HF Propagation Ground-wave Sky-wave Ionospheric regions VHF/UHF Propagation Line-of-sight Tropospheric Bending and
More informationChapter 6 Propagation
Chapter 6 Propagation Al Penney VO1NO Objectives To become familiar with: Classification of waves wrt propagation; Factors that affect radio wave propagation; and Propagation characteristics of Amateur
More informationChapter 7 HF Propagation. Ionosphere Solar Effects Scatter and NVIS
Chapter 7 HF Propagation Ionosphere Solar Effects Scatter and NVIS Ionosphere and Layers Radio Waves Bent by the Ionosphere Daily variation of Ionosphere Layers Ionospheric Reflection Conduction by electrons
More informationVHF/UHF Beyond FM Bob Witte KØNR Page 1
VHF/UHF Beyond FM Technical Coordinator Colorado Section Page 1 Objective The objective of this presentation is to provide an introduction to operating on VHF/UHF, going beyond the usual FM / Repeater
More information1. Terrestrial propagation
Rec. ITU-R P.844-1 1 RECOMMENDATION ITU-R P.844-1 * IONOSPHERIC FACTORS AFFECTING FREQUENCY SHARING IN THE VHF AND UHF BANDS (30 MHz-3 GHz) (Question ITU-R 218/3) (1992-1994) Rec. ITU-R PI.844-1 The ITU
More informationRadio Propagation - VHF and higher
Radio Propagation - VHF and higher (Without the Mathematics) Presented by Dr John Worsnop G4BAO RSGB Propagation Studies Committee RadCom GHz bands Columnist With a little help from http://www.mike-willis.com/tutorial/propagation.html
More informationOBJECTIVES: PROPAGATION INTRO RADIO WAVES POLARIZATION LINE OF SIGHT, GROUND WAVE, SKY WAVE IONOSPHERE REGIONS PROPAGATION, HOPS, SKIPS ZONES THE
WAVE PROPAGATION OBJECTIVES: PROPAGATION INTRO RADIO WAVES POLARIZATION LINE OF SIGHT, GROUND WAVE, SKY WAVE IONOSPHERE REGIONS PROPAGATION, HOPS, SKIPS ZONES THE IONOSPHERIC LAYERS ABSORPTION AND FADING
More informationFCC Technician License Course
FCC Technician License Course 2014-2018 FCC Element 2 Technician Class Question Pool Presented by: Tamiami Amateur Radio Club (TARC) WELCOME To the third of 4, 3-hour classes presented by TARC to prepare
More informationGlobal Maps with Contoured Ionosphere Properties Some F-Layer Anomalies Revealed By Marcel H. De Canck, ON5AU. E Layer Critical Frequencies Maps
Global Maps with Contoured Ionosphere Properties Some F-Layer Anomalies Revealed By Marcel H. De Canck, ON5AU In this column, I shall handle some possibilities given by PROPLAB-PRO to have information
More informationMaximum Usable Frequency
Maximum Usable Frequency 15 Frequency (MHz) 10 5 0 Maximum Usable Frequency Usable Frequency Window Lowest Usable Frequency Solar Flare 6 12 18 24 Time (Hours) Radio Blackout Usable Frequency Window Ken
More informationSpace Weather and Propagation JANUARY 14, 2017
Space Weather and Propagation MARTIN BUEHRING -KB4MG ELEC T R ICAL ENGINEER, A M AT EUR EXTRA CLASS LICENSE HOLDER JANUARY 14, 2017 Why know about Space Weather? Our SUN has an enormous affect not only
More informationChapter 13: Wave Propagation. EET-223: RF Communication Circuits Walter Lara
Chapter 13: Wave Propagation EET-223: RF Communication Circuits Walter Lara Electrical to Electromagnetic Conversion Since the atmosphere is not a conductor of electrons (instead a good insulator), electrical
More informationReading 28 PROPAGATION THE IONOSPHERE
Reading 28 Ron Bertrand VK2DQ http://www.radioelectronicschool.com PROPAGATION THE IONOSPHERE The ionosphere is a region of the upper atmosphere extending from a height of about 60 km to greater than 500
More informationIonospheric Propagation
Ionospheric Nick Massey VA7NRM 1 Electromagnetic Spectrum Radio Waves are a form of Electromagnetic Radiation Visible Light is also a form of Electromagnetic Radiation Radio Waves behave a lot like light
More informationCRITICAL FREQUENCY By Marcel H. De Canck, ON5AU
CRITICAL FREQUENCY By Marcel H. De Canck, ON5AU Before reading onward, it would be good to refresh your knowledge about refraction rules in the section on Refraction of the earlier "Wave Propagation Direction
More informationGeneral 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 informationAmateur Radio Service Technician Class
Amateur Radio Service Technician Class Exam Preparation Class January 2019 Session 2 Roland K. Smith K7OJL Phone: (435) 849-1946 Email: rolandksmith@gmail.com 1 TechClass-Session2.key - January 11, 2019
More informationChapter 15: Radio-Wave Propagation
Chapter 15: Radio-Wave Propagation MULTIPLE CHOICE 1. Radio waves were first predicted mathematically by: a. Armstrong c. Maxwell b. Hertz d. Marconi 2. Radio waves were first demonstrated experimentally
More informationVHF Propagation Overview 5-Oct-2016
VHF Propagation Overview 5-Oct-2016 G0RVM 1 VHF Propagation Where in the radio spectrum is VHF? 30MHz to 300MHz for radio amateurs its 50MHz, 70MHz & 144MHz or 6m, 4m & 2m Name some types of VHF propagation?
More informationRF Propagation. By Tim Kuhlman, PE KD7RUS
RF Propagation By Tim Kuhlman, PE KD7RUS Purpose of this Seminar In this seminar we will attempt to answer the following questions: What is RF propagation? What are the different types of propagation?
More informationRF Propagation. By Tim Kuhlman, PE KD7RUS
RF Propagation By Tim Kuhlman, PE KD7RUS Purpose of this Seminar In this seminar we will attempt to answer the following questions: What is RF propagation? What are the different types of propagation?
More informationPolarization orientation of the electric field vector with respect to the earth s surface (ground).
Free space propagation of electromagnetic waves is often called radio-frequency (rf) propagation or simply radio propagation. The earth s atmosphere, as medium introduces losses and impairments to the
More informationIntroduction to HF Propagation. Rick Fletcher, W7YP FVARC November 20, 2018
Introduction to HF Propagation Rick Fletcher, W7YP FVARC November 20, 2018 Topics The HF Bands How HF propagation works Overview by HF band Sources of solar and propagation information Working HF during
More informationS.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 informationCurrent Solar Cycle Poor propagation No propagation Checking HF propagation. Coping with poor HF propagation Q&A
Topics Current Solar Cycle Poor propagation No propagation Checking HF propagation Predictive (HF propagation prediction software) Empirical (beacons, WSPR, PSKREPORTER and operator testing) Coping with
More informationMUF: Spokane to Cleveland October, 2100 UTC
MHz What Mode of Propagation Enables JT65/JT9/FT8? Carl Luetzelschwab K9LA August 2017 Revision 1 (thanks W4TV) The purpose of this article is not to rigorously analyze how much improvement each JT mode
More informationDefinitions of Technical Terms
Definitions of Technical Terms Terms Ammeter Amperes, Amps Band Capacitor Carrier Squelch Diode Dipole Definitions How is an ammeter usually connected = In series with the circuit What instrument is used
More informationHigh Frequency Propagation (and a little about NVIS)
High Frequency Propagation (and a little about NVIS) Tom McDermott, N5EG August 18, 2010 September 2, 2010 Updated: February 7, 2013 The problem Radio waves, like light waves, travel in ~straight lines.
More informationCHAPTER 6. Propagation
CHAPTER 6 Propagation TOC: INTRO RADIO WAVES POLARIZATION LINE OF SIGHT, GROUND & SKY WAVES IONOSPHERE REGIONS IONOSPHERIC LAYERS PROPAGATION, HOPS, SKIPS ZONES ABSORPTION AND FADING SOLAR ACTIVITY AND
More information4/29/2012. 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 informationThe CY9C 6-Meter Opening on August 24, 2016 Carl Luetzelschwab K9LA October 2016
The CY9C 6-Meter Opening on August 24, 2016 Carl Luetzelschwab K9LA October 2016 During the summer of 2016 (specifically August 19 29), St. Paul Island was activated as CY9C on 160-Meters through 6-Meters
More informationEmergency Antennas VHF / UHF - FM. HF Voice, CW, or Digital
1 Emergency Antennas VHF / UHF - FM HF Voice, CW, or Digital 2 Antennas for VHF Quarter Wave Vertical Half Wave Vertical Vertical Dipole J-Pole 3 Design Parameters Primarily line of sight Mounted on trunk
More information3 Methods of radiocommunication
+ + & & * * ) ) From the ITU Emergency Telecommunications handbook; prepared for the 54 th JOTA 2011. 3 Methods of radiocommunication 3.1 Frequencies Radio frequencies should be selected according to propagation
More informationSw earth Dw Direct wave GRw Ground reflected wave Sw Surface wave
WAVE PROPAGATION By Marcel H. De Canck, ON5AU Electromagnetic radio waves can propagate in three different ways between the transmitter and the receiver. 1- Ground waves 2- Troposphere waves 3- Sky waves
More informationChapter 5.0 Antennas Section 5.1 Theory & Principles
Chapter 5.0 Antennas Section 5.1 Theory & Principles G3C11 (B) p.135 Which of the following antenna types will be most effective for skip communications on 40-meters during the day? A. A vertical antenna
More informationRadio Communication. Presentation created by: András Balogh
Radio Communication Presentation created by: András Balogh AM and FM The goal is to transmit a modulating signal S(t) via a wave sin(ωt). In case of AM, the product of the modulation is f(t)=(a+s(t))*sin(ωt);
More informationNVIS PROPAGATION THEORY AND PRACTICE
NVIS PROPAGATION THEORY AND PRACTICE Introduction Near-Vertical Incident Skywave (NVIS) propagation is a mode of HF operation that utilizes a high angle reflection off the ionosphere to fill in the gap
More informationRadio Frequency Propagation: A General Overview from LF to VHF.
Radio Frequency Propagation: A General Overview from LF to VHF. Presented by: Mike Parkin GØJMI Slide 1 Introduction Mike Parkin: First licensed as G8NDJ in 1977. Became GØJMI in 1988. Interests in Radio
More informationEvolution of the WSJT Digital Modes
Evolution of the WSJT Digital Modes Mike Hasselbeck WB2FKO New Mexico TechFest 25 February 2017 WSJT: A software package for digital radio communication Weak Signal communication by Professor Joe Taylor
More informationSCARS Technician / General License Course Week 4
SCARS Technician / General License Course Week 4 Radio Wave Propagation: Getting from Point A to Point B Radio waves propagatein many ways depending on Frequency of the wave Characteristics of the environment
More informationRegional and Long Distance Skywave Communications
Regional and Long Distance Skywave Communications F LAYER SKYWAVE ELEVATION ANGLE STATION - A STATION - B Ken Larson KJ6RZ October 2010 1 Page Title 3 1.0 Introduction 3 2.0 The Earth s Ionosphere 6 3.0
More information# DEFINITIONS TERMS. 2) Electrical energy that has escaped into free space. Electromagnetic wave
CHAPTER 14 ELECTROMAGNETIC WAVE PROPAGATION # DEFINITIONS TERMS 1) Propagation of electromagnetic waves often called radio-frequency (RF) propagation or simply radio propagation. Free-space 2) Electrical
More informationHalf-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 informationBroad Principles of Propagation 4C4
Broad Principles of Propagation ledoyle@tcd.ie 4C4 Starting at the start All wireless systems use spectrum, radiowaves, electromagnetic waves to function It is the fundamental and basic ingredient of
More informationWave Propagation and Antenna Engineering
Wave Propagation and Antenna Engineering Wave Propagation and Antenna Engineering SANJAY KUMAR Air Commodore (Retd.) Former AOC, 9 BRD, IAF Pune and Former Principal Adviser Defence Avionics Research
More informationWSJT: Digital Communication in Extreme Conditions
WSJT: Digital Communication in Extreme Conditions Mike Hasselbeck WB2FKO Socorro Hamfest 15 October 2016 WSJT: A software package for digital radio communication Weak Signal communication by Professor
More informationMuscle Shoals Amateur Radio Club. Extra License Class Training Session 2
Muscle Shoals Amateur Radio Club Extra License Class Training Session 2 Review Test Pool Question Review Questions? Syllabus Week 1 9/4/18: Commission s Rules (6 question areas) Week 2 9/11/18: Operating
More informationCHAPTER 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 information1. What are the applications of loop antenna? (May2011) 2. Define Pattern Multiplication (May2011)
UNIT-II WIRE ANTENNAS AND ANTENNA ARRAYS 1. What are the applications of loop antenna? (May2011) 2. Define Pattern Multiplication (May2011) 3. A uniform linear array contains 50 isotropic radiation with
More informationChapter 4. Propagation, Antennas and Feed Lines. Propagation Black magic topic #1. How do radio waves get from point A to point B?
Chapter 4 Propagation, Antennas and Feed Lines Propagation Black magic topic #1. How do radio waves get from point A to point B? 1 Radio Wave Propagation Normally radio waves travel in a straight line,
More informationFundamentals 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 informationEC 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 informationDiscover the Magic. Revision 2. HF Radio
Discover the Magic Revision 2 Of HF Radio Welcome to Worldwide Communications This presentation is designed to introduce the new or recently upgraded ham to HF radio, and has been modified for the Canadian
More informationAntennas and Propagation
Mobile Networks Module D-1 Antennas and Propagation 1. Introduction 2. Propagation modes 3. Line-of-sight transmission 4. Fading Slides adapted from Stallings, Wireless Communications & Networks, Second
More informationRadar Reprinted from "Waves in Motion", McGourty and Rideout, RET 2005
Radar Reprinted from "Waves in Motion", McGourty and Rideout, RET 2005 What is Radar? RADAR (Radio Detection And Ranging) is a way to detect and study far off targets by transmitting a radio pulse in the
More informationIf maximum electron density in a layer is less than n', the wave will penetrate the layer
UNIT-7 1. Briefly the describe the terms related to the sky wave propagation: virtual heights, critical frequency, maximum usable frequency, skip distance and fading? Ans: Sky wave propagation: It is also
More informationPropagation Tool.
Propagation Propagation Tool http://www.hamqsl.com/solar.html The Ionosphere is made up of several layers at varying heights above the ground: The lowest level is the D Layer (37 to 56 miles), which
More informationANTENNA THEORY WAVE PROPAGATION HF ANTENNAS
ANTENNA THEORY WAVE PROPAGATION & HF ANTENNAS FREQUENCY SPECTRUM INFORMATION Frequency range American designator below 300 Hz..ELF (extremely Low Frequency) 300-3000 Hz..ILF (Intermediate Low Frequency)
More informationTechnician License Course Chapter 2 Radio and Electronics Fundamentals. PHYS 401 Spring 2009 P. Reiff, Rice University
Technician License Course Chapter 2 Radio and Electronics Fundamentals PHYS 401 Spring 2009 P. Reiff, Rice University Basic Station Organization Station Equipment Receiver Transmitter Antenna Power Supply
More informationUNIT Derive the fundamental equation for free space propagation?
UNIT 8 1. Derive the fundamental equation for free space propagation? Fundamental Equation for Free Space Propagation Consider the transmitter power (P t ) radiated uniformly in all the directions (isotropic),
More informationSession2 Antennas and Propagation
Wireless Communication Presented by Dr. Mahmoud Daneshvar Session2 Antennas and Propagation 1. Introduction Types of Anttenas Free space Propagation 2. Propagation modes 3. Transmission Problems 4. Fading
More informationAntennas and Propagation. Chapter 5
Antennas and Propagation Chapter 5 Introduction An antenna is an electrical conductor or system of conductors Transmission - radiates electromagnetic energy into space Reception - collects electromagnetic
More informationAmateur Extra Manual Chapter 9.4 Transmission Lines
9.4 TRANSMISSION LINES (page 9-31) WAVELENGTH IN A FEED LINE (page 9-31) VELOCITY OF PROPAGATION (page 9-32) Speed of Wave in a Transmission Line VF = Velocity Factor = Speed of Light in a Vacuum Question
More informationAntennas and Propagation. Prelude to Chapter 4 Propagation
Antennas and Propagation Prelude to Chapter 4 Propagation Introduction An antenna is an electrical conductor or system of conductors for: Transmission - radiates electromagnetic energy into space (involves
More informationAntennas and Propagation
Antennas and Propagation Chapter 5 Introduction An antenna is an electrical conductor or system of conductors Transmission - radiates electromagnetic energy into space Reception - collects electromagnetic
More informationResonant and Nonresonant Lines. Input Impedance of a Line as a Function of Electrical Length
Exercise 3-3 The Smith Chart, Resonant Lines, EXERCISE OBJECTIVES Upon completion of this exercise, you will know how the input impedance of a mismatched line varies as a function of the electrical length
More informationFUNDAMENTALS OF MICROWAVE COMMUNICATION EXAMINATION Module/SubCourse: SS0345 Edition: 6
FUNDAMENTALS OF MICROWAVE COMMUNICATION EXAMINATION Module/SubCourse: SS0345 Edition: 6 Instructions The final examination contains multiple-choice questions covering all lessons. This is an open-book
More informationIntermediate Course (5) Antennas and Feeders
Intermediate Course (5) Antennas and Feeders 1 System Transmitter 50 Ohms Output Standing Wave Ratio Meter Antenna Matching Unit Feeder Antenna Receiver 2 Feeders Feeder types: Coaxial, Twin Conductors
More informationRADIOWAVE PROPAGATION
RADIOWAVE PROPAGATION Physics and Applications CURT A. LEVIS JOEL T. JOHNSON FERNANDO L. TEIXEIRA The cover illustration is part of a figure from R.C. Kirby, "Introduction," Lecture 1 in NBS Course in
More informationPART 1 RECOMMENDATION ITU-R P.1144 GUIDE TO THE APPLICATION OF THE PROPAGATION METHODS OF RADIOCOMMUNICATION STUDY GROUP 3
Rec. ITU-R P.1144 1 PART 1 SECTION P-A: TEXTS OF GENERAL INTEREST Rec. ITU-R P.1144 RECOMMENDATION ITU-R P.1144 GUIDE TO THE APPLICATION OF THE PROPAGATION METHODS OF RADIOCOMMUNICATION STUDY GROUP 3 (1995)
More informationKINGS COLLEGE OF ENGINEERING. DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING Academic Year (Even Sem) QUESTION BANK (AUTT-R2008)
KINGS COLLEGE OF ENGINEERING DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING Academic Year 2012-2013(Even Sem) QUESTION BANK (AUTT-R2008) SUBJECT CODE /NAME: EC 1352 / ANTENNEA AND WAVE PROPAGATION
More information1 Propagating Light. Reflection and Refraction
PRACTICE FINAL 1 1) An ac source of period T and maximum voltage V is connected to a single unknown ideal element that is either a resistor, and inductor, or a capacitor. At time t = 0 the voltage is zero.
More informationGet Discount Coupons for your Coaching institute and FREE Study Material at COMMUNICATION SYSTEMS
COMMUNICATION SYSTEMS 1. BASICS OF COMMUNICATION 2. AMPLITUDE MODULATION Get Discount Coupons for your Coaching institute and FREE Study Material at www.pickmycoaching.com 1 BASICS OF COMMUNICATION 1.
More informationIonospheric Propagation
Ionospheric Propagation Page 1 Ionospheric Propagation The ionosphere exists between about 90 and 1000 km above the earth s surface. Radiation from the sun ionizes atoms and molecules here, liberating
More informationRange Considerations for RF Networks
TI Technology Days 2010 Range Considerations for RF Networks Richard Wallace Abstract The antenna can be one of the most daunting components of wireless designs. Most information available relates to large
More informationGeneral Class License Theory III. Dick Grote K6PBF
General Class License Theory III Dick Grote K6PBF K6pbfdick@gmail.com 1 Introduction In this session we will learn about: Feed Lines Antennas Safety As in the other theory classes, we will try to present
More informationAntennas & 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 informationTransforms and electrical signal into a propagating electromagnetic wave OR vise versa. - Transducer goes both ways. TX and RX antennas have
Gary Rondeau AF7NX Transforms and electrical signal into a propagating electromagnetic wave OR vise versa. - Transducer goes both ways. TX and RX antennas have different jobs. For TX want to generate as
More informationAntenna 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 informationRadiation and Particles from the. Sun
2017 Radiation and Particles from the Photons Sun Photons (300000km/s ~ 8m 20s) radio waves, infra red, visible light, ultra violet, x-ray, x galactic waves, Solar Flux (30000km/s ~ 8m 20s) The 10.7 cm
More informationAntennas and Propagation. Chapter 5
Antennas and Propagation Chapter 5 Introduction An antenna is an electrical conductor or system of conductors Transmission - radiates electromagnetic energy into space Reception - collects electromagnetic
More informationTechnical and operational characteristics of land mobile MF/HF systems
Recommendation ITU-R M.1795 (03/2007) Technical and operational characteristics of land mobile MF/HF systems M Series Mobile, radiodetermination, amateur and related satellite services ii Rec. ITU-R M.1795
More informationTechnician License Course Chapter 4. Lesson Plan Module 9 Antenna Fundamentals, Feed Lines & SWR
Technician License Course Chapter 4 Lesson Plan Module 9 Antenna Fundamentals, Feed Lines & SWR The Antenna System Antenna: Transforms current into radio waves (transmit) and vice versa (receive). Feed
More informationChapter 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 informationDartmouth College SuperDARN Radars
Dartmouth College SuperDARN Radars Under the guidance of Thayer School professor Simon Shepherd, a pair of backscatter radars were constructed in the desert of central Oregon over the Summer and Fall of
More informationHigh-frequency radio wave absorption in the D- region
Utah State University From the SelectedWorks of David Smith Spring 2017 High-frequency radio wave absorption in the D- region David Alan Smith, Utah State University This work is licensed under a Creative
More informationNVIS Near Vertical Incident Skywave 5/25/2015 1
NVIS Near Vertical Incident Skywave 5/25/2015 1 The Problem 8/15/06 2 Introduction to NVIS What Is NVIS? What are the advantages of NVIS? How to deploy NVIS. 8/15/06 3 What Is NVIS? NVIS, or Near Vertical
More informationKINGS COLLEGE OF ENGINEERING DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING QUESTION BANK
KINGS COLLEGE OF ENGINEERING DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING QUESTION BANK SUB.NAME : ANTENNAS & WAVE PROPAGATION SUB CODE : EC 1352 YEAR : III SEMESTER : VI UNIT I: ANTENNA FUNDAMENTALS
More informationImproved Ionospheric Propagation With Polarization Diversity, Using A Dual Feedpoint Cubical Quad Loop
Improved Ionospheric Propagation With Polarization Diversity, Using A Dual Feedpoint Cubical Quad Loop by George Pritchard - AB2KC ab2kc@optonline.net Introduction This Quad antenna project covers a practical
More informationTechnician Licensing Class T9
Technician Licensing Class T9 Amateur Radio Course Monroe EMS Building Monroe, Utah January 11/18, 2014 January 22, 2014 Testing Session Valid dates: July 1, 2010 June 30, 2014 Amateur Radio Technician
More informationRadio Propagation Fundamentals
Radio Propagation Fundamentals Concept of Electromagnetic Wave Propagation Mechanisms Modes of Propagation Propagation Models Path Profiles Link Budget Fading Channels Electromagnetic (EM) Waves EM Wave
More informationLast year I described several Low Band RX antennas that would enable you to hear DX stations on 160, 80 and 40M. This will show you how to build
Last year I described several Low Band RX antennas that would enable you to hear DX stations on 160, 80 and 40M. This will show you how to build transmit antennas that will help you break the pileups!
More information