Monitoring Times 2000 INDEX
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5.1 Optical Nanostrip Antenna
Copyright Undertaking This thesis is protected by copyright, with all rights reserved. By reading and using the thesis, the reader understands and agrees to the following terms: 1. The reader will abide by the rules and legal ordinances governing copyright regarding the use of the thesis. 2. The reader will use the thesis for the purpose of research or private study only and not for distribution or further reproduction or any other purpose. 3. The reader agrees to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage. IMPORTANT If you have reasons to believe that any materials in this thesis are deemed not suitable to be distributed in this form, or a copyright owner having difficulty with the material being included in our database, please contact [email protected] providing details. The Library will look into your claim and consider taking remedial action upon receipt of the written requests. Pao Yue-kong Library, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong http://www.lib.polyu.edu.hk INVENSTIGATION OF SOLAR ELECTRIC SYSTEMS BASED ON NANO RECTENNA WANG JIAJIE, IVAN Ph.D The Hong Kong Polytechnic University 2014 I II The Hong Kong Polytechnic University Department of Building Services Engineering Investigation of Solar Electric Systems Based on Nano Rectenna WANG Jiajie, Ivan A thesis submitted in partial fulfillment of the requirements for the Degree of Doctor of Philosophy September 2013 III IV CERTIFICATE OF ORIGINALITY I hereby declare that this thesis is my own work and that, to the best of my knowledge and belief, it produces no material previously published or written nor material which has been accepted for the award of any other degree or diploma, except where due acknowledgement has been made in the text. -
FCC-06-11A1.Pdf
Federal Communications Commission FCC 06-11 Before the FEDERAL COMMUNICATIONS COMMISSION WASHINGTON, D.C. 20554 In the Matter of ) ) Annual Assessment of the Status of Competition ) MB Docket No. 05-255 in the Market for the Delivery of Video ) Programming ) TWELFTH ANNUAL REPORT Adopted: February 10, 2006 Released: March 3, 2006 Comment Date: April 3, 2006 Reply Comment Date: April 18, 2006 By the Commission: Chairman Martin, Commissioners Copps, Adelstein, and Tate issuing separate statements. TABLE OF CONTENTS Heading Paragraph # I. INTRODUCTION.................................................................................................................................. 1 A. Scope of this Report......................................................................................................................... 2 B. Summary.......................................................................................................................................... 4 1. The Current State of Competition: 2005 ................................................................................... 4 2. General Findings ....................................................................................................................... 6 3. Specific Findings....................................................................................................................... 8 II. COMPETITORS IN THE MARKET FOR THE DELIVERY OF VIDEO PROGRAMMING ......... 27 A. Cable Television Service .............................................................................................................. -
Antenna Theory and Design SECOND EDITION
Antenna Theory and Design SECOND EDITION Warren L. Stutzman Gary A. Thiele WILEY Contents Chapter 1 • Antenna Fundamentals and Definitions 1 1.1 Introduction 1 1.2 How Antennas Radiate 4 1.3 Overview of Antennas 8 1.4 Electromagnetic Fundamentals 12 1.5 Solution of Maxwell's Equations for Radiation Problems 16 1.6 The Ideal Dipole 20 1.7 Radiation Patterns 24 1.7.1 Radiation Pattern Basics 24 1.7.2 Radiation from Line Currents 25 1.7.3 Far-Field Conditions and Field Regions 28 1.7.4 Steps in the Evaluation of Radiation Fields 31 1.7.5 Radiation Pattern Definitions 33 1.7.6 Radiation Pattern Parameters 35 1.8 Directivity and Gain 37 1.9 Antenna Impedance, Radiation Efficiency, and the Short Dipole 43 1.10 Antenna Polarization 48 References 52 Problems 52 Chapter 2 • Some Simple Radiating Systems and Antenna Practice 56 2.1 Electrically Small Dipoles 56 2.2 Dipoles 59 2.3 Antennas Above a Perfect Ground Plane 63 2.3.1 Image Theory 63 2.3.2 Monopoles 66 2.4 Small Loop Antennas 68 2.4.1 Duality 68 2.4.2 The Small Loop Antenna 71 2.5 Antennas in Communication Systems 76 2.6 Practical Considerations for Electrically Small Antennas 82 References 83 Problems 84 Chapter 3 • Arrays 87 3.1 The Array Factor for Linear Arrays 88 3.2 Uniformly Excited, Equally Spaced Linear Arrays 99 3.2.1 The Array Factor Expression 99 3.2.2 Main Beam Scanning and Beamwidth 102 3.2.3 The Ordinary Endfire Array 103 3.2.4 The Hansen-Woodyard Endfire Array 105 3.3 Pattern Multiplication 107 3.4 Directivity of Uniformly Excited, Equally Spaced Linear Arrays 112 3.5 Nonuniformly -
Cetiie B Tia Nature Red Acted
Probabilistic Methods for Systems Engineering with Application to Nanosatellite Laser Communications by Emily B. Clements Submitted to the Department of Aeronautics and Astronautics in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 2018 Massachusetts Institute of Technology 2018. All rights reserved. Autholr Signature redacted (J Department of Aeronautics and Astronautics May 24,2018 Cetiie b tianature red acted Kerri L. Cahoy Associate Professor of Aeronautics and Astronautics red acted Thesis Supervisor Certified by ... Signatu re ........................ David 0. Caplan Senior Staff, MIT Lincoln Laboratory Certified by, S ignature redacted Jeffrey A. Mendenhall Lincoln Laboratory C ignature red acted Senior Staff, MIT Certified by. ................................... David W. Miller Jerome Hunsaker Professor of Aeronauticq and Astronautics Accepted by......... .................. Signature redacted MASSACHUSETTS INSTITUTE Hamsa Balakrishnan OF TECHNOLOGY Associate Professor of Aeronautics and Astronautics JUN 28 2018 Chair, Graduate Program Committee LIBRARIES ARCHIVES 2 Probabilistic Methods for Systems Engineering with Application to Nanosatellite Laser Communications by Emily B. Clements Submitted to the Department of Aeronautics and Astronautics on May 24, 2018, in partial fulfillment of the requirements for the degree of Doctor of Philosophy Abstract Risk-tolerant platforms such as nanosatellites may be able to accept moderate perfor- mance uncertainty -
High Frequency Communications – an Introductory Overview
High Frequency Communications – An Introductory Overview - Who, What, and Why? 13 August, 2012 Abstract: Over the past 60+ years the use and interest in the High Frequency (HF -> covers 1.8 – 30 MHz) band as a means to provide reliable global communications has come and gone based on the wide availability of the Internet, SATCOM communications, as well as various physical factors that impact HF propagation. As such, many people have forgotten that the HF band can be used to support point to point or even networked connectivity over 10’s to 1000’s of miles using a minimal set of infrastructure. This presentation provides a brief overview of HF, HF Communications, introduces its primary capabilities and potential applications, discusses tools which can be used to predict HF system performance, discusses key challenges when implementing HF systems, introduces Automatic Link Establishment (ALE) as a means of automating many HF systems, and lastly, where HF standards and capabilities are headed. Course Level: Entry Level with some medium complexity topics Agenda • HF Communications – Quick Summary • How does HF Propagation work? • HF - Who uses it? • HF Comms Standards – ALE and Others • HF Equipment - Who Makes it? • HF Comms System Design Considerations – General HF Radio System Block Diagram – HF Noise and Link Budgets – HF Propagation Prediction Tools – HF Antennas • Communications and Other Problems with HF Solutions • Summary and Conclusion • I‟d like to learn more = “Critical Point” 15-Aug-12 I Love HF, just about On the other hand… anybody can operate it! ? ? ? ? 15-Aug-12 HF Communications – Quick pretest • How does HF Communications work? a. -
ZS6BKW Vs G5RV Antenna
ZZS6BS6BKWKW vsvs G5RG5RVV Antenna Patterns/SWR at 40 ft Center height, 27 ft end height ~148 Degree Included Angle Compiled By: Larry James LeBlanc 2010 For the AARA Ham Radio Club Note: All graphs computed using MMANA GAL http://mmhamsoft.amateur-radio.ca/mmana/index.htm ZSZS6BK6BKWW // G5RVG5RV WhaWhatt isis it?it? In the mid-1980s, Brian Austin (ZS6BKW) ran computer analysis to develop an antenna System that, for the maximum number of HF bands possible, would permit a low Standing Wave Ratio (SWR) without antenna tuner to interface with a 50-Ohm coaxial cable as the main feed line. He identified a range of lengths which, when combined with a matching ladder line length, would provide this characteristic. According to an acknowledged expert in computer antenna design and modeling, L. B. Cebik: “Of all the G5RV antenna system cousins, the ZS6BKW antenna system has come closest to achieving the goal that is part of the G5RV mythology: a multi-band HF antenna consisting of a single wire and simple matching system to cover as many of the amateur HF bands as possible.” Both are “good” antennas and will work well in defined situations. This presentation is not designed to “bash” the G5RV, but to possibly convince you or a new ham to enjoy the benefits of lower SWR, lower loss, and greater signal strength by using the ZS6BKW version of a ladder line fed dipole. ZZSS66BBKWKW // GG55RRVV WWhhyy II liklikee itit 1. Has low swr in several ham bands at the matching point at the end of the ladder line resulting in lower losses in the coax cable. -
The G5rv Antenna
SUCCESSFUL WIRE ANTENNAS Band (metres) 80 40 30 20 17 15 12 10 6 2 L1 end (2) 168 89.4 63.2 45 35.3 30 25.6 22.4 12.7 4.37 L2 centre (2) 65 34.7 24.6 17.5 13.7 11.7 9.97 8.72 4.95 1.70 L3 total size 467 248 176 125 98 83.3 71.2 62.3 35.4 12.2 L4 stubs 48.6 25.8 18.3 13 10.2 8.66 7.4 6.47 3.68 1.26 L5 height 120 64 45 32 25 21 18 16 10 10 Inductor (μH) 25.9 11.7 7.3 4.9 3.4 2.8 2.2 1.9 0.85 0.13 Gain (dBi) 11.4 11.4 11.3 11.2 11.1 11.0 11.0 11.0 11.4 10.9 Freq (MHz) 3.8 7.15 10.1 14.2 18.12 21.3 24.93 28.5 50.2 146 Table 4.3: Lengths (in feet) of an HGSW beam for 10 amateur bands. insulators as shown. The lower ends of the two lines should be stripped and bent over and soldered together. The resultant active line length must be 13ft. The dis- tance from the centre insulator to the ladder line should be 17.5ft. If you have a lot of wind in your area you might want to tie a 1oz lead fishing sinker to the bottom of each of the phasing lines. Alternately a string can be attached and tied to some secure point below the antenna. -
Nested Loop Antennas This Low-Cost Five Band Loop Array Blends Into the Background
Nested Loop Antennas This low-cost five band loop array blends into the background. G. Scott Davis, N3FJP This multi-band nested loop antenna array replaces my tribander Yagi, which is only up 20 feet. Inspired by suggestions from Bill Wisel, K3KEI, I first tried a full wave 20 meter band square loop antenna. On the air comparisons with my low Yagi confirmed instantly that this design was a hands-down winner for working both local and distant stations. I replaced that mono-band loop with a nested loop array for the 20, 17, 15, 12, and 10 meter bands. The antenna blends into the surroundings, so I needed the morning sun shining directly on it to snap the lead photo. This became a nice father-son project with my son Brad, KB3MNE. Here’s how we built the antenna. Construction We constructed the square loops shown in Figure 1 according to the dimensions in Table 1. The loops hang from a tree limb in the vertical plane. Because I feed them This stealthy nested loop is almost invisible among the trees. from the bottom corners, the loops radiate horizontal polarization. Calculate the perimeter size, P, of each holes through the pipe for the loop wire. screws into the PVC to hang the dipole loop by dividing the frequency in MHz After you run the wire through the holes, connectors seen in Figure 2. wrap a bit of electrical tape on each side of into 1005 feet. Table 1 shows the loop Matching and Feeding dimensions. Start with the 20 meter loop, the wire next to the pipe to keep the wire from sliding and to give the pipe additional Each loop antenna feed point impedance is the largest loop. -
4DTV Sidecar April01.Qxd
The Motorola 4DTV Digital Sidecar The Motorola 4DTV® digital sidecar gives you access to up to 200 digital channels currently available to C-Band customers. DigiCipher® II Programming: The Motorola 4DTV® digital sidecar give you access to up to 200 digital The Motorola 4DTV sidecar is a digital satellite channels currently available to C-Band customers. receiver that you add to your current analog C- Band system allowing you to access all the digital Free Digital Channels: If you already have access to the analog version of a channel many programmers will channels available to C-Band customers. The way give you the digital version for free. it works is simple: your analog receiver controls your dish allowing you to continue to receive Easy to Use: The Motorola 4DTV digital satellite sidecar provides features that make channel surfing a channels the same way you do now. The Motorola breeze. Search for future programs up to 7 days in 4DTV sidecar provides access to up to 200 digital advance or customize your Motorola 4DTV sidecar channels currently available to C-Band while giving with 4 favorite categories. you the digital features that make your satellite Access to High Definition: The Motorola 4DTV sidecar system easier to use. comes with a port that will allow you to access high definition television with the HDD-200 decoder. The benefit of upgrading your C-Band system with the Motorola 4DTV digital sidecar is that the 3-in-1 Remote: Control your sidecar, VCR and TV with 4DTV digital sidecar is designed to work with one remote. -
Reconfigurable Plasma Antenna Array by Using Fluorescent Tube for Wi-Fi Application
RADIOENGINEERING, VOL. 25, NO. 2, JUNE 2016 275 Reconfigurable Plasma Antenna Array by Using Fluorescent Tube for Wi-Fi Application Hajar JA’AFAR1, Mohd Tarmizi ALI 2, Ahmad Nazri DAGANG3, Idnin Pasya IBRAHIM2, Nur Aina HALILI2, Hanisah MOHD ZALI2 1Faculty of Electrical Engineering, Universiti Teknologi MARA (Terengganu), Sura Hujung 23000 Dungun, Malaysia 2Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia 3 School of Ocean Engineering, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia [email protected] Manuscript received March 19, 2016 Abstract. This paper presents a new design of reconfigura- generated by UV laser irradiation, or by laser initiated pre- ble plasma antenna array using commercial fluorescent ionization followed by high voltage break down to form tube. A round shape reconfigurable plasma antenna array the main conducting channel or by simply using commer- is proposed to collimate beam radiated by an omnidirec- cial fluorescence tube to serve as reflector, or by much tional antenna (monopole antenna) operating at 2.4 GHz more expensive electron beam [2]. There were also exotic in particular direction. The antenna design consists of methods like explosion generating plasma antenna for a monopole antenna located at the center of a circular alu- fusion research. The plasma will be present when electron minum ground. The monopole antenna is surrounded by and nucleus that form the atom is no longer able to stay a cylindrical shell of conducting plasma. The plasma shield together due to high kinetic energy. It happens due to the consists of 12 commercial fluorescent tubes aligned in electrons are stripped out from the atoms. -
Class C Pool of Questions
Class C Pool of Questions T2 1. What is the most common repeater frequency offset in the 2 meter band? T2 2. What is the national calling frequency for FM simplex operations in the 70 cm band? T2 3. What is a common repeater frequency offset in the 70 cm band? T2 4. What is an appropriate way to call another station on a repeater if you know the other station's call sign? T2 5. How should you respond to a station calling CQ? T2 6. What must an amateur operator do when making on-air transmissions to test equipment or antennas? T2 7. Which of the following is true when making a test transmission? T2 8. What is the meaning of the procedural signal “CQ”? T2 9. What brief statement is often transmitted in place of “CQ” to indicate that you are listening on a repeater? T2 10. What is a band plan, beyond the privileges established by the SMA? T2 11. Which of the following is an SMA rule regarding power levels used in the amateur bands, under normal, non-distress circumstances? T2 12. Which of the following is a guideline to use when choosing an operating frequency for calling CQ? T2B – VHF/UHF operating practices: SSB phone; FM repeater; simplex; splits and shifts; CTCSS; DTMF; tone squelch; carrier squelch; phonetics; operational problem resolution; Q signals T2 1. What is the term used to describe an amateur station that is transmitting and receiving on the same frequency? T2 2. What is the term used to describe the use of a sub-audible tone transmitted with normal voice audio to open the squelch of a receiver? T2 3. -
Notes on HF Discone Antennas
Notes on HF Discone Antennas L. B. Cebik, W4RNL The discone antenna is a broadband basic antenna originally designed for VHF-UHF service. Indeed, it is a staple for upper-range scanning receivers. Developed during WWII by A. G. Kandoian, and brought to the attention of radio amateurs in the later 1940s, the following years saw conversions of the design to HF use. Amateurs have used it from 160 meters up through 10 meters, although the operating passband for any single implementation is limited to about a 2.5:1 frequency range. Even though the antenna is quite basic in concept, its shape seems to elicit strange reactions from newer amateurs. The reactions run from simple quizzical looks to occasional bizarre explanations of its operation. In these notes we shall look at the antenna with a series of inquiries. We shall start by putting the antenna into its proper class. Then we shall turn to questions of modeling the antenna, sorting out what we can glean from models and what we cannot. Since operating bandwidth is the most pressing question in many minds, we shall next look at that matter, followed by questions of performance. The performance facets of HF versions of the antenna over ground are perhaps the most important, since that is the environment in which we must use the antenna, if we choose to build one. To set a proper framework for judgment by the prospective builder, we shall look at a few other antenna designs that may be relevant. In order to focus our attention on the properties of the HF discone, we shall confine our attention to creating one to cover the upper HF set of amateur allocations from 14 to 30 MHz.