VHA Directive 0320.09 Resilient High Frequency Radio Network
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PUBLIC BROADCASTING: a MEDIUM in SEARCH of SOLUTIONS John W
PUBLIC BROADCASTING: A MEDIUM IN SEARCH OF SOLUTIONS JoHN W. MACY, JR.* INTRODUCTION In its simplest and most comprehensive definition, a communications system is a process in which creative communicators become aware of the expressed and some- times unexpressed needs of the users of the system and responsively collect and provide information, entertainment, and other resources toward the satisfaction of these needs. Despite the often quoted and now popular belief that in electronic com- munications systems "the medium is the message,"' the design of a system in which the message is itself the message-and the medium is merely a means of delivering a diversity of messages of intrinsic value to the users-is a mandate for radio and television in the decade of the 1970s. This is one of the basic philosophies behind the approach of the Corporation for Public Broadcasting (CPB) as it builds and develops the public sector of broadcasting. Some time ago Robert Oppenheimer was quoted as saying, "What is new is new not because it has never been there before, but because it has changed in quality."2 This is surely what is new about the Corporation for Public Broadcasting. But to understand the nature and direction of the qualitative changes brought about by its creation and activities, it is necessary to look first at what was there before and how the Corporation came into being. I BACKGROUND OF PUBLIC BROADCASTING Over the past fifty years, the American public, through its elected representatives and otherwise, has made a series of choices to encourage the development of a public alternative in the field of communications. -
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. -
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internet resources John H. Barnett Global voices, global visions International radio and television broadcasts via the Web he world is calling—are you listening? used international broadcasting as a method of THere’s how . Internet radio and tele communicating news and competing ideologies vision—tuning into information, feature, during the Cold War. and cultural programs broadcast via the In more recent times, a number of reli Web—piqued the interest of some educators, gious broadcasters have appeared on short librarians, and instructional technologists in wave radio to communicate and evangelize the 1990s. A decade ago we were still in the to an international audience. Many of these early days of multimedia content on the Web. media outlets now share their programming Then, concerns expressed in the professional and their messages free through the Internet, literature centered on issues of licensing, as well as through shortwave radio, cable copyright, and workable business models.1 television, and podcasts. In my experiences as a reference librar This article will help you find your way ian and modern languages selector trying to to some of the key sources for freely avail make Internet radio available to faculty and able international Internet radio and TV students, there were also information tech programming, focusing primarily on major nology concerns over bandwidth usage and broadcasters from outside the United States, audio quality during that era. which provide regular transmissions in What a difference a decade makes. Now English. Nonetheless, one of the benefi ts of with the rise of podcasting, interest in Web tuning into Internet radio and TV is to gain radio and TV programming has recently seen access to news and knowledge of perspec resurgence. -
Radio Network Coding Requires Logarithmic Overhead
2019 IEEE 60th Annual Symposium on Foundations of Computer Science (FOCS) Radio Network Coding Requires Logarithmic Overhead Klim Efremenko Gillat Kol Raghuvansh R. Saxena Ben-Gurion University Princeton University Princeton University [email protected] [email protected] [email protected] Abstract—We consider the celebrated radio network then, a neighbor u of the node v receives v’s transmission model for abstracting communication in wireless networks. if and only if u decides to receive at time t and v is the In this model, in any round, each node in the network may only neighbor of u that transmits at time t. broadcast a message to all its neighbors. However, a node is able to hear a message broadcast by a neighbor only if no The (noiseless) radio network model received a lot collision occurred, meaning that it was the only neighbor of attention over the last few decades, and has an ever broadcasting. growing number of wireless and distributed applications. While the (noiseless) radio network model received a On the other hand, the effect of noise on radio networks lot of attention over the last few decades, the effect is not well understood, although wireless communication of noise on radio networks is still not well understood. In this paper, we take a step forward and show that errors are extremely common in practice. In our previous making radio network protocols resilient to noise may paper [EKS18], we took a step forward and initiated the require a substantial performance overhead. Specifically, study of interactive coding for the single-hop (clique) we construct a multi-hop network and a communication network, following the great work of [Gam87], [Gal88], protocol over this network that works in T rounds when [GKS08]. -
High-Frequency Radiowa Ve Probing of the High-Latitude Ionosphere
RAYMOND A. GREENWALD HIGH-FREQUENCY RADIOWAVE PROBING OF THE HIGH-LATITUDE IONOSPHERE During the past several years, a program of high-frequency radiowave studies of the high-latitude ionosphere has been developed in the APL Space Department. Studies are now being conducted on the formation and motion of high-latitude ionospheric electron density irregularities, using a sophisti cated high-frequency radar system installed at Goose Bay, .Labrador. The radar antenna is also being used to receive signals from a beacon transmitter located at Thule, Greenland. This information is providing a better understanding of the spatial and temporal variability of high-latitude propagation channels and their relationship to disturbances in the magnetosphere-ionosphere system . INTRODUCTION turbances prior to their impingement on the magneto At altitudes above 100 kilometers, the atmosphere sphere is quite limited. Therefore, we still have only of the earth gradually changes from a predominantly limited success in forecasting sudden changes in the neutral medium to an increasingly ionized gas or plas high-latitude ionosphere and consequently in high ma. The ionization is caused chiefly by a combination latitude radiowave propagation. of solar extreme ultraviolet radiation and, at high lati In order for space scientists to obtain a better un tudes, particle precipitation from the earth's magne derstanding of the various interactions occurring tosphere. Because of its ionized nature between 100 among the solar wind, the magnetosphere, and the ion and 1000 kilometers, this part of the atmosphere is osphere, active measurement programs are conduct commonly referred to as the ionosphere. In this re ed in all three regions. -
FCC-21-42A1.Pdf
Federal Communications Commission FCC 21-42 Before the Federal Communications Commission Washington, D.C. 20554 In the Matter of ) ) Sponsorship Identification Requirements for ) MB Docket No. 20-299 Foreign Government-Provided Programming ) ) REPORT AND ORDER Adopted: April 22, 2021 Released: April 22, 2021 By the Commission: Acting Chairwoman Rosenworcel and Commissioner Starks issuing separate statements. TABLE OF CONTENTS Heading Paragraph # I. INTRODUCTION .................................................................................................................................. 1 II. BACKGROUND .................................................................................................................................... 5 III. DISCUSSION ...................................................................................................................................... 12 A. Entities or Individuals Whose Involvement in the Provision of Programming Triggers a Disclosure ...................................................................................................................................... 14 B. Scope of Foreign Programming that Requires a Disclosure .......................................................... 24 C. Reasonable Diligence ..................................................................................................................... 35 D. Contents and Frequency of Required Disclosure of Foreign Sponsorship .................................... 49 E. Concerns About Overlap with Other Statutory -
Apostolate Logo Here
Apostolate Logo Here Address City State Zip Phone Website STARTING CATHOLIC RADIO __________ (Bishop / Archbishop / Cardinal) Approval of Project We seek the blessing and support of __________ (Bishop / Archbishop / Cardinal Name) for our local Catholic radio station. Prayer is the Foundation of Any Successful Effort "The fruit of the apostolate is directly dependent upon the depth of the spiritual life." (John Paul II - Address on the Jubilee of the Lay-Apostolate) License _______ (Apostolate Name) will be licensee for Radio Station _______ (Call Letters / Frequency / Band) Papal Plea for Catholic Radio Every Pope since the invention of the radio has asked for the medium to be used for the purpose of spreading the Faith. Vatican II repeated this plea and added emphasis on the role of the laity. In its document on Social Communications, the Council said that it is a responsibility of the laity to start Catholic radio stations, and that it would be "shameful" if these efforts were not supported by the faithful. LISTENER SUPPORTED __________ (Apostolate Name) is a 501(c)(3) not-for-profit corporation. As such, we do not have commercials on the radio or other commercial income. The station is supported through listener tax- deductible donations. Without broad listener support, and the commitment and generosity of EWTN, Catholic radio would not be viable on local AM or FM in the community. Parish Pledge Talks One of the most successful methods used in building audience awareness and paying for the operation of local Catholic radio stations is parish pledge talks. A short six-minute scripted talk is given at a weekend slate of Masses. -
UNIT -1 Microwave Spectrum and Bands-Characteristics Of
UNIT -1 Microwave spectrum and bands-characteristics of microwaves-a typical microwave system. Traditional, industrial and biomedical applications of microwaves. Microwave hazards.S-matrix – significance, formulation and properties.S-matrix representation of a multi port network, S-matrix of a two port network with mismatched load. 1.1 INTRODUCTION Microwaves are electromagnetic waves (EM) with wavelengths ranging from 10cm to 1mm. The corresponding frequency range is 30Ghz (=109 Hz) to 300Ghz (=1011 Hz) . This means microwave frequencies are upto infrared and visible-light regions. The microwaves frequencies span the following three major bands at the highest end of RF spectrum. i) Ultra high frequency (UHF) 0.3 to 3 Ghz ii) Super high frequency (SHF) 3 to 30 Ghz iii) Extra high frequency (EHF) 30 to 300 Ghz Most application of microwave technology make use of frequencies in the 1 to 40 Ghz range. During world war II , microwave engineering became a very essential consideration for the development of high resolution radars capable of detecting and locating enemy planes and ships through a Narrow beam of EM energy. The common characteristics of microwave device are the negative resistance that can be used for microwave oscillation and amplification. Fig 1.1 Electromagnetic spectrum 1.2 MICROWAVE SYSTEM A microwave system normally consists of a transmitter subsystems, including a microwave oscillator, wave guides and a transmitting antenna, and a receiver subsystem that includes a receiving antenna, transmission line or wave guide, a microwave amplifier, and a receiver. Reflex Klystron, gunn diode, Traveling wave tube, and magnetron are used as a microwave sources. -
HF Radio Propagation
Introduction to HF Radio Propagation 1. The Ionosphere 1.1 The Regions of the Ionosphere In a region extending from a height of about 50 km to over 500 km, most of the molecules of the atmosphere are ionised by radiation from the Sun. This region is called the ionosphere (see Figure 1.1). Ionisation is the process in which electrons, which are negatively charged, are removed from neutral atoms or molecules to leave positively charged ions and free electrons. It is the ions that give their name to the ionosphere, but it is the much lighter and more freely moving electrons which are important in terms of HF (high frequency) radio propagation. The free electrons in the ionosphere cause HF radio waves to be refracted (bent) and eventually reflected back to earth. The greater the density of electrons, the higher the frequencies that can be reflected. During the day there may be four regions present called the D, E, F1 and F2 regions. Their approximate height ranges are: • D region 50 to 90 km; • E region 90 to 140 km; • F1 region 140 to 210 km; • F2 region over 210 km. At certain times during the solar cycle the F1 region may not be distinct from the F2 region with the two merging to form an F region. At night the D, E and F1 regions become very much depleted of free electrons, leaving only the F2 region available for communications. Only the E, F1 and F2 regions refract HF waves. The D region is very important though, because while it does not refract HF radio waves, it does absorb or attenuate them (see Section 1.5). -
Public Service Broadcasting in Transition: a Documentary Reader
University of Pennsylvania ScholarlyCommons Other Publications from the Center for Global Center for Global Communication Studies Communication Studies (CGCS) 11-2011 Public Service Broadcasting in Transition: A Documentary Reader Monroe Price University of Pennsylvania, [email protected] Marc Raboy Follow this and additional works at: https://repository.upenn.edu/cgcs_publications Part of the Broadcast and Video Studies Commons Recommended Citation Price, Monroe and Raboy, Marc. (2011). Public Service Broadcasting in Transition: A Documentary Reader. Other Publications from the Center for Global Communication Studies. Retrieved from https://repository.upenn.edu/cgcs_publications/1 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/cgcs_publications/1 For more information, please contact [email protected]. Public Service Broadcasting in Transition: A Documentary Reader Abstract This is a book of documents, comments, and cases that has been prepared, at the request of the European Institute for the Media, for the use of government officials and citizens interested in strengthening public service broadcasting in transition societies. In this book we try to provide a small chest of tools and background information that will be of assistance. We start, in Chapter 1, with an overview of some of the general principles of public service broadcasting, and include pertinent comments on each of them. Here, as throughout the book, we concentrate on issues of governance and financing, with some attention as well ot issues surrounding programming. In Chapter 2, we turn to current issues in the European-level debate, partly from the perspective of European expectations and standards that are employed in evaluation and accession processes. -
The BBC's Distribution Arrangements for Its UK Public Services
The BBC’s distribution arrangements for its UK Public Services A report by Mediatique presented to the BBC Trust Finance Committee November 2013 BRITISH BROADCASTING CORPORATION The BBC’s distribution arrangements for its UK Public Services A report by Mediatique presented to the BBC Trust Finance Committee November 2013 Presented to Parliament by the Secretary of State for Culture, Media and Sport by Command of Her Majesty February 2014 © BBC 2013 The text of this document may be reproduced free of charge in any format or medium providing that it is reproduced accurately and not in a misleading context. The material must be acknowledged as BBC copyright and the document title specified. Where third party material has been identified, permission from the respective copyright holder must be sought BBC Trust response to Mediatique’s value for money study: the BBC’s distribution arrangements for its UK Public Services Introduction The BBC exists to educate, inform and entertain through a broad range of high quality programmes and services on TV, Radio and Online. It is also tasked with distributing this content to audiences across the country in ways that are convenient to them. In 2012-13 the cost of these distribution arrangements was £233million or 6.5 percent of the licence fee. The BBC Trust exists to maximise the value audiences receive in return for the licence fee. To help it do this, the Trust commissioned Mediatique to carry out a value for money review of the BBC’s distribution arrangements in the UK. This is one of a number of value for money reports received by the Trust from various organisations, including the NAO, all of which help the Trust to identify ways to improve the way the BBC is run.