UNIT -1 Microwave Spectrum and Bands-Characteristics Of
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Kindergarten High Frequency Word List
Kindergarten High Frequency Word List The following 40 words are the high frequency Kindergarten words. They are divided according to their probability of occurring in the corresponding DRA text levels. However, many of these words can occur throughout all levels. The goal is for all students to read, write, and use these words correctly by the end of Kindergarten. Level 1 Level 2 Level 3 Level 4 Level 5 a me to yes big I go in cat for is at on dog he the you like up she mom we my with this dad it by said look can no love play went see am do was and C:\Users\metcalfr\Downloads\K_5_High_Frequency_Word_Lists (2).docx October 2014 First Grade High Frequency Word list The goal is for all students to read, write, and use these words (and words from the kindergarten word list) correctly by the end of first grade. after have please all her saw an here should are him so as his some be I’m thank because if that but into them came just then come know they could little there day make us did many very end new want from not were get of what goes one when going or where good our who had out will has over would your C:\Users\metcalfr\Downloads\K_5_High_Frequency_Word_Lists (2).docx October 2014 Second Grade High Frequency Word List The goal is for all students to read, write, and use these words (and the words from preceding grade level word lists) correctly by the end of second grade. -
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. -
Revisions to Microwave Spectrum Utilization Policies in the Range of 1-20 Ghz
SP 1-20 GHz January 1995 Spectrum Management Spectrum Utilization Policy Revisions to Microwave Spectrum Utilization Policies in the Range of 1-20 GHz Notice No. DGTP-002-95 Amended by: DGTP-006-99 Amendments to the Microwave Spectrum Utilization Policies in the 1-3 GHz Frequency Range (October 1999) DGTP-006-97 Proposals to Provide New Opportunities for the Use of the Radio Spectrum in the 1-20 GHz Frequency Range (August 1997) DGTP-007-97 Spectrum Policy Provisions to Permit the Use of Digital Radio Broadcasting Installations to Provide to Non-Broadcasting Services (September 1997) DGTP-004-97 Licence Exempt Personal Communications Services in the Frequency Band 1910-1930 MHz (April 1997) DGTP-005-95 / Policy and Call for Applications: Wireless Personal Communications Services in the 2 GHz Range, Implementing PCS DGRB-002-95 in Canada (June 1995) DGTP-007-00 / Policy and Licensing Procedures for the Auction of the Additional PCS Spectrum in the 2 GHz Frequency Range DGRB-005-00 (June 2000) DGTP-003-01 Revisions to the Spectrum Utilization Policy for Services in the Frequency Range 2285-2483.5 MHz (June 2001) DGRB-003-03 Policy and Licensing Procedures for the Auction of Spectrum Licences in the 2300 MHz and 3500 MHz Bands (September 2003) DGRB-006-99 Policy and Licensing Procedures - Multipoint Communications Systems in the 2500 MHz Range (June 1999) DGTP-004-04 Revisions to Allocations in the Band 2500-2690 MHz and Consultation on Spectrum Utilization (April 2004) DGTP-008-04 Revisions to Spectrum Utilization Policies in the 3-30 GHz -
Radio Spectrum a Key Resource for the Digital Single Market
Briefing March 2015 Radio spectrum A key resource for the Digital Single Market SUMMARY Radio spectrum refers to a specific range of frequencies of electromagnetic energy that is used to communicate information. Applications important for society such as radio and television broadcasting, civil aviation, satellites, defence and emergency services depend on specific allocations of radio frequency. Recently the demand for spectrum has increased dramatically, driven by growing quantities of data transmitted over the internet and rapidly increasing numbers of wireless devices, including smartphones and tablets, Wi-Fi networks and everyday objects connected to the internet. Radio spectrum is a finite natural resource that needs to be managed to realise the maximum economic and social benefits. Countries have traditionally regulated radio spectrum within their territories. However despite the increasing involvement of the European Union (EU) in radio spectrum policy over the past 10 to 15 years, many observers feel that the management of radio spectrum in the EU is fragmented in ways which makes the internal market inefficient, restrains economic development, and hinders the achievement of certain goals of the Digital Agenda for Europe. In 2013, the European Commission proposed legislation on electronic communications that among other measures, provided for greater coordination in spectrum management in the EU, but this has stalled in the face of opposition within the Council. In setting out his political priorities, Commission President Jean-Claude Juncker has indicated that ambitious telecommunication reforms, to break down national silos in the management of radio spectrum, are an important step in the creation of a Digital Single Market. The Commission plans to propose a Digital Single Market package in May 2015, which may again address this issue. -
PSAD-79-48A an Unclassified Version of a Classified Report
STUDYBY THE STAFFOF THE‘U.S. General Accounting Office An Unclassified Version Of A Classified Report Entitled “The Navy’s Strategic Communications Systems--Need For Management Attention And Decisionmaking” Peacetime communications systems provide reliable day-to-day communications to the strategic submarine force. However, the Navy’s most survivable wartime communica- tions link to nuclear-powered strategic submarines--the TACAMO aircraft--has cer- tain problems which need attention. Also, the Navy should reconsider whether another peacetime communications system--the extremely low frequency system--is needed. COMPTROLLER GENERAL OF THE UNITED STATES WASHINGTON. O.C. 20548 B-168707 To the President of the Senate and the Speaker of the House of Representatives This report is an unclassified version of a SECRET report (PSAD-79-48, March 19, 1979) to the Congress that describes the various communications systems used by our strategic submarine force and questions the need for the extremely low frequency system. Also, the report addresses the need for support of the TACAMO comnunications system. We made this study because of widespread congressional interest in strategic communications systems, especially the TACAMO and proposed extremely low frequency systems. These issues are receiving increased recognition, and the Navy plans to spend millions of dollars to improve the TACAMO system and conduct research and development on the extremely low frequency system. Copies of this report are being sent to the Secretary of Defense and the Secretary of the Navy. Comptroller General of the United States COMPTROLLER GENERAL'S THE NAVY'S STRATEGIC REPORT TO THE CONGRESS COMMUNICATIONS SYSTEMS--NEED FOR MANAGEMENT ATTENTION AND DECISIONMAKING ------DIGEST Peacetime communications systems provide reliable day-to-day communications to the strategic submarine force. -
Chapter 4, Current Status, Knowledge Gaps, and Research Needs Pertaining to Firefighter Radio Communication Systems
NIOSH Firefighter Radio Communications CHAPTER IV: STRUCTURE COMMUNICATIONS ISSUES Buildings and other structures pose difficult problems for wireless (radio) communications. Whether communication is via hand-held radio or personal cellular phone, communications to, from, and within structures can degrade depending on a variety of factors. These factors include multipath effects, reflection from coated exterior glass, non-line-of-sight path loss, and signal absorption in the building construction materials, among others. The communications problems may be compounded by lack of a repeater to amplify and retransmit the signal or by poor placement of the repeater. RF propagation in structures can be so poor that there may be areas where the signal is virtually nonexistent, rendering radio communication impossible. Those who design and select firefighter communications systems cannot dictate what building materials or methods are used in structures, but they can conduct research and select the radio system designs and deployments that provide significantly improved radio communications in this extremely difficult environment.4 Communication Problems Inherent in Structures MULTIPATH Multipath fading and noise is a major cause of poor radio performance. Multipath is a phenomenon that results from the fact that a transmitted signal does not arrive at the receiver solely from a single straight line-of-sight path. Because there are obstacles in the path of a transmitted radio signal, the signal may be reflected multiple times and in multiple paths, and arrive at the receiver from various directions along various paths, with various signal strengths per path. In fact, a radio signal received by a firefighter within a building is rarely a signal that traveled directly by line of sight from the transmitter. -
Newsgathering Transmission Techniques
NEWSGATHERING TRANSMISSION TECHNIQUES Ennes Workshop – Miami, FL March 8, 2013 Kevin Dennis Regional Sales Manager 2 Vislink is Built on a Firm Foundation 3 Presentation Outline • Advancements in video encoding technology – H.264 versus MPEG-2 • Advancements in licensed microwave technology – Implementing HD/SD H.264 encoding – Modulation, FEC, high power Linear Amps • Advancements in bandwidth capacity of public access networks (Cellular and Wi-Fi) – 3G, 4G, LTE, WiMax – HD/SD Bonded Cellular Video Transmission • Comparison of strengths and weaknesses of licensed microwave transmission versus public network transmissions Newsgathering Transmission Techniques • Advancements in video encoding technology • Advancements in licensed microwave technology • Advancements in bandwidth capacity of public access networks (Cellular and Wi-Fi) • Comparison of strengths and weaknesses of licensed microwave transmission versus public network transmissions H.264 (MPEG-4 AVC / Part10) versus MPEG-2 • H.264/MPEG-4 AVC is a block-oriented motion-compensation based codec standard • First version of the standard was completed in 2003 • H.264 video compression is significantly more efficient than MPEG-2 encoding providing two-fold improvement as compared to MPEG-2 • H.264 HD encoding not excessively expensive to implement as compared to first MPEG-2 encoders H.264 (MPEG-4 AVC) vs. MPEG-2 H.264 is approximately twice as efficient as MPEG-2 Video quality comparison of H.264 (solid blue line with squares) and MPEG-2 (dotted red line with circles) as a function of bit rate compared to 100 Mbps source material. H.264 (MPEG-4 AVC) vs. MPEG-2 Low Motion Video - there is very little video quality difference between H.264 and MPEG-2 Video Images posted by Jan Ozer, Video Technology Instructor H.264 (MPEG-4 AVC) vs. -
Overcoming Barriers to Providing Mobile Coverage Everywhere
WHITE PAPER Overcoming Barriers to Providing Mobile Coverage Everywhere Published by © 2018 Introduction New international efforts to tackle digital While connecting the unconnected is an inequality have made expanding broadband important driver for expanding coverage, it’s not infrastructure a global priority. The United the only one. Operators in developing and Nations’ Broadband Commission for Sustainable developed countries are under pressure to build Development recently set ambitious targets for out infrastructure for a variety of business and 2025 to connect the remaining half of the regulatory reasons. Depending on the market, world’s population to the Internet. The goals operator requirements include meeting coverage include a mandate for all countries to establish obligations attached to spectrum licenses, funded national broadband plans, or broadband providing national emergency or disaster universal service requirements, as well as making recovery services, reducing roaming and leased affordable broadband services available in line costs and growing their customer base. developing countries (costing less than 2% of monthly gross national income per capita) by 2025. Mobile Internet connectivity will be key to “Mobile Internet achieving these broadband sustainable development goals that will bring economic and connectivity is key to social benefits to billions of people worldwide. There are two categories of unconnected achieving sustainable people: those that are covered by mobile broadband, 3G or 4G, infrastructure but do not development goals that use Internet services and those with no access to mobile networks at all. According to the will bring economic and GSMA, about 3.3 billion people are covered but not connected, while 1 billion people are not social benefits to billions covered. -
Spectrum and the Technological Transformation of the Satellite Industry Prepared by Strand Consulting on Behalf of the Satellite Industry Association1
Spectrum & the Technological Transformation of the Satellite Industry Spectrum and the Technological Transformation of the Satellite Industry Prepared by Strand Consulting on behalf of the Satellite Industry Association1 1 AT&T, a member of SIA, does not necessarily endorse all conclusions of this study. Page 1 of 75 Spectrum & the Technological Transformation of the Satellite Industry 1. Table of Contents 1. Table of Contents ................................................................................................ 1 2. Executive Summary ............................................................................................. 4 2.1. What the satellite industry does for the U.S. today ............................................... 4 2.2. What the satellite industry offers going forward ................................................... 4 2.3. Innovation in the satellite industry ........................................................................ 5 3. Introduction ......................................................................................................... 7 3.1. Overview .................................................................................................................. 7 3.2. Spectrum Basics ...................................................................................................... 8 3.3. Satellite Industry Segments .................................................................................... 9 3.3.1. Satellite Communications .............................................................................. -
A Review Paper on Microwave Transmission Using Reflector Antennas
International Journal of Scientific & Engineering Research Volume 8, Issue 10, October-2017 ISSN 2229-5518 251 A Review Paper on Microwave Transmission using Reflector Antennas Sandeep Kumar Singh [1],Sumi Kumari[2] Sr. Lecturer, Dept. of ECE, JBIT, Dehradun [1], Asst. Professor, Dept. of ECE, VGIET, Jaipur[2] [email protected][1] [email protected][2] Abstract: The conventional optimization problem of the beamed microwave energy transmission system is considered. The criterion of maximum efficiency of power intercept is parabolic function of distribution on the transmitting antenna. It is shown that under such a condition of amplitude distribution becomes more uniform than as the unconditional optimization. In this case, we can substantially increase the power radiated by the transmitting antenna losing the power intercept no more than 2%. Keywords: Parabolic Reflector Antenna, Radio Relay, Antenna Gain, Cassegrain Feed. I.INTRODUCTION limited to line of sight propagation; they cannot pass around hills or mountains as lower frequency radio waves can. Microwave radiation is generally defined as that electromagnetic radiation having wavelengths between radio waves and infrared III.ANTENNA radiation. Microwave radiation can be forced to travel in specially designed waveguides. Microwave radiation can be transmitted An antenna (or aerial) is an electrical device which converts through space or through the atmosphere in a microwave beam electric currents into radio waves, and vice versa. It is usually used from a microwave antenna and the microwave energy can be with a radio transmitter or radio receiver. In transmission, a radio collected with a microwave antenna. Microwave antennas are used transmitter applies an oscillating radio frequency electric current to for transmitting and receiving microwave radiation. -
The Electromagnetic Spectrum
The Electromagnetic Spectrum Wavelength/frequency/energy MAP TAP 2003-2004 The Electromagnetic Spectrum 1 Teacher Page • Content: Physical Science—The Electromagnetic Spectrum • Grade Level: High School • Creator: Dorothy Walk • Curriculum Objectives: SC 1; Intro Phys/Chem IV.A (waves) MAP TAP 2003-2004 The Electromagnetic Spectrum 2 MAP TAP 2003-2004 The Electromagnetic Spectrum 3 What is it? • The electromagnetic spectrum is the complete spectrum or continuum of light including radio waves, infrared, visible light, ultraviolet light, X- rays and gamma rays • An electromagnetic wave consists of electric and magnetic fields which vibrates thus making waves. MAP TAP 2003-2004 The Electromagnetic Spectrum 4 Waves • Properties of waves include speed, frequency and wavelength • Speed (s), frequency (f) and wavelength (l) are related in the formula l x f = s • All light travels at a speed of 3 s 108 m/s in a vacuum MAP TAP 2003-2004 The Electromagnetic Spectrum 5 Wavelength, Frequency and Energy • Since all light travels at the same speed, wavelength and frequency have an indirect relationship. • Light with a short wavelength will have a high frequency and light with a long wavelength will have a low frequency. • Light with short wavelengths has high energy and long wavelength has low energy MAP TAP 2003-2004 The Electromagnetic Spectrum 6 MAP TAP 2003-2004 The Electromagnetic Spectrum 7 Radio waves • Low energy waves with long wavelengths • Includes FM, AM, radar and TV waves • Wavelengths of 10-1m and longer • Low frequency • Used in many -
Microwave Receivers with Direct Digitization
Microwave Receivers with Direct Digitization Dmitri E. Kirichenko, Timur V. Filippov, and Deepnarayan Gupta HYPRES, Elmsford, NY, 10532, U.S.A. Abstract — Superconductor analog-to-digital converters integrated circuit (IC) technology with Niobium (Nb) (ADCs) and ultrafast digital circuitry enable processing of Josephson junctions (JJs), currently offer the best solution. microwave signals entirely in the digital domain. We have Superconductor ICs combine high-linearity, wideband ADCs designed and demonstrated a wide variety of continuous-time bandpass delta-sigma modulators using Josephson junction [2] and ultrafast digital logic, called rapid single flux quantum comparators. Featuring sampling frequencies up to 30 GHz, (RSFQ). A family of superconductor digital-RF receiver single-chip digital receivers have been demonstrated by (called ADR) chips (Fig. 1), comprising an ADC and a digital connecting a rapid single flux quantum (RSFQ) digital circuitry channelizer circuit, performing digital down-conversion and with these ADCs. These receiver chips, cooled to 4 K by cryogen- filtering, have been demonstrated. Notably, a digital-RF free refrigerators, have been used with room-temperature digital processors to demonstrate reception of microwave signals for X- receiver system, comprising a cryocooled ADR chip, was band satellite communications and Link-16 data links. To date, demonstrated reception of live satellite communication signals the highest frequency of direct digitization is 21 GHz for satellite in the X-band (7.25-7.75 GHz) [3]. In this paper, we focus on communication. We report recent advances in ADC design to ADCs for various microwave frequency bands ranging from 1 obtain higher dynamic range. GHz to 21 GHz. Index Terms — Analog-to-digital converter, RSFQ, cryogenic, Digital Output (I) SATCOM.