High-Frequency Radiowa Ve Probing of the High-Latitude Ionosphere
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
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. -
Overview of Sensors for Applications
OVERVIEW OF SENSORS FOR APPLICATIONS Deepak Putrevu Head, MTDD/AMHTDG EM SPECTRUM Visible 0.4-0.7μm Near infrared (NIR) 0.7-1.5μm Optical Infrared Shortwave infrared (SWIR) 1.5-3.0μm Mid-wave infrared (MWIR) 3.0-8.0μm (OIR) Region Longwave IR(LWIR)/Thermal IR(TIR) 8.0-15μm Far infrared (FIR) Beyond15μm Gamma Rays X Rays UV Visible NIR SWIR Thermal IR Microwave P-band: ~0.25 – 1 GHz Microwave Region L-band: 1 -2 GHz S-band: 2-4 GHz •Sensors are 24x365 C-band: 4-8 GHz •Signal data characteristics X-band: 8-12 GHz unique to the microwave region of the EM spectrum Ku-band: 12-18 GHz K-band: 18-26 GHz •Response is primarily governed by geometric Ka-band: 26-40 GHz structures and hence V-band: 40 - 75 GHz complementary to optical W-band: 75-110 GHz imaging mm-wave: 110 – 300GHz Basic Interactions between Electromagnetic Energy and the Earth’s Surface Incident Power reflected, ρP Reflectivity: The fractional part of the radiation, P incident radiation that is reflected by the surface. Power absorbed, αP Absorptivity: the fractional part of the = Power emitted, εP incident radiation that is absorbed by the surface. Power transmitted, τP Emissivity: The ratio of the observed flux emitted by a body or surface to that of a P= Pr + Pt + Pa blackbody under the same condition. 푃 푃 푃 푟 + 푡 + 푎 = 1 푃 푃 푃 Transmissivity: The fractional part of the ρ + τ + α =1 radiation transmitted through the medium. At thermal equilibrium, absorption and emission are the same. -
Digital Radio Broadcasting Network in the Arctic Region
______________________________________________________PROCEEDING OF THE 24TH CONFERENCE OF FRUCT ASSOCIATION Digital Radio Broadcasting Network in the Arctic Region Oleg Varlamov, Vladimir Varlamov, Anna Dolgopyatova Moscow Technical University of Communications and Informatics Moscow, Russia [email protected], [email protected], [email protected] Abstract—Successful economic development of the Arctic 81°), where the geostationary orbit (GEO) is observed very low zone is impossible without creating a continuous information field above the horizon and only a small portion of it is visible, that covers its entire territory and is available not only at where the satellites of the required operator are not always stationary objects, but primarily in moving vehicles - ships, cars, present, providing information fields using satellites located on airplanes, etc. This information field must consist from the GEO is not possible. Approximately from 81 ° to the poles transmission of audio information (broadcasting programs), data (weather maps, ice conditions, etc.), navigation signals, alerts and GEO from the surface of the Earth is not visible even information about emergencies, and must be reserved from theoretically. different sources. As a backup system (and in the coming years, The most promising for the formation of the main the main one) it is advisable to use single-frequency digital information field in the Arctic zone can be considered satellite broadcasting networks of the Digital Radio Mondiale standard in the low frequency range. This is the most economical system for systems in highly elliptical (HEO) or low Earth (LEO) orbits. covering remote areas. For the use of these systems, have all the At the same time, the high cost of such systems, the long period necessary regulatory framework and standard high-efficiency of infrastructure deployment and the limited lifespan, combined radio transmitters. -
Cisco Broadband Data Book
Broadband Data Book © 2020 Cisco and/or its affiliates. All rights reserved. THE BROADBAND DATABOOK Cable Access Business Unit Systems Engineering Revision 21 August 2019 © 2020 Cisco and/or its affiliates. All rights reserved. 1 Table of Contents Section 1: INTRODUCTION ................................................................................................. 4 Section 2: FREQUENCY CHARTS ........................................................................................ 6 Section 3: RF CHARACTERISTICS OF BROADCAST TV SIGNALS ..................................... 28 Section 4: AMPLIFIER OUTPUT TILT ................................................................................. 37 Section 5: RF TAPS and PASSIVES CHARACTERISTICS ................................................... 42 Section 6: COAXIAL CABLE CHARACTERISTICS .............................................................. 64 Section 7: STANDARD HFC GRAPHIC SYMBOLS ............................................................. 72 Section 8: DTV STANDARDS WORLDWIDE ....................................................................... 80 Section 9: DIGITAL SIGNALS ............................................................................................ 90 Section 10: STANDARD DIGITAL INTERFACES ............................................................... 100 Section 11: DOCSIS SIGNAL CHARACTERISTICS ........................................................... 108 Section 12: FIBER CABLE CHARACTERISTICS ............................................................... -
Portable Shortwave Receivers
Portable Shortwave Receivers ● Longwave, AM, FM and Shortwave ELITE SATELLIT ● VHF Air Band ● HD Radio Reception ● RDS Display ● Superior Sensitivity and Selectivity ● Dual Conversion Design ● Huge 5.7 Inch Backlit Display ● Drift-free Digital Phase Lock Loop ● Direct Frequency and Band Entry ● Single Sideband Synchronous Detector ● Selectable Bandwidths ● High Dynamic Range ● Dual Programmable Clocks ● Dual Event Programmable Timers ● Stereo Line Level Input ● Stereo Line Level Output ● Earphone Jack ● Separate Bass and Treble Controls ● Adjustable AGC: Fast or Slow ● Telescopic Antenna AM/FM/SW ● Battery (4xD) or Included AC Adapter ● Scan and Search ● 1700 Total Memories (500 alphanumeric) ● Deluxe Carry Bag The Elite Satellit is simply the finest full-sized portable in the world. The Elite Satellit is an elegant confluence of performance, features and capabilities. The look, feel and finish of this radio is superb. The solid, quality feel is second to none. The digitally synthesized, dual conversion shortwave tuner covers all long wave, mediums wave (AM) and shortwave frequencies. HD Radio improves audio fidelity and adds additional programming without a subscription fee. Adjacent frequency interference can be minimized or eliminated with a choice of three bandwidths [7.0, 4.0, 2.5 kHz]. The sideband selectable Synchronous AM Detector further minimizes adjacent frequency interference and reduces fading distortion of AM signals. IF Passband Tuning is yet another advanced feature that functions in AM and SSB modes to reject interference. AGC is selectable at fast or slow. High dynamic range permits the detection of weak signals in the presence of strong signals. All this coupled with great sensitivity will bring in stations from every part of the globe. -
Hans Knot International Radio Report April 2016 Welcome to Another
Hans Knot International Radio Report April 2016 Welcome to another edition of the International Radio Report. Thanks all for your e mails, memories, photos, questions and more. Part of the report is what was left after the March edition was totally filled and so let’s go with this edition in which first there’s space for a story I wrote last months after again doing some research: ‘Ronan O’Rahilly, Georgie Fame and the Blue Fames. Where it really went wrong!’ On this subject I’ve written before but let’s go back in time and also add some new facts to it: ‘Was Ronan O’Rahilly the manager of Georgie Fame?’ I can tell you there was a problem with an important instrument. When in April 1964 Granada Television came with an edition of the ‘World in action’ series, which was a production from Michael Hodges, they informed the television public about a new form of Piracy, the watery pirates. Two radio ships bringing music and entertainment under the names of Radio Caroline and Radio Atlanta. Radio Caroline was the first 20th century Pirate off the British coast with programs, at that stage, for 12 hours a day. Interviews with the Caroline people were made in the offices of Queen Magazine in the city of London and included – among others – Jocelyn Stevens and the then 23-year old Irish Ronan O’Rahilly. During this documentary it became known, which we would also read in several newspapers in the then following weeks, that Ronan O’Rahilly had started his radiostation Caroline as he couldn’t get his artists played on stations like Radio Luxembourg. -
Downloaded 09/25/21 09:30 PM UTC
1434 JOURNAL OF HYDROMETEOROLOGY VOLUME 9 NASA Cold Land Processes Experiment (CLPX 2002/03): Local Scale Observation Site ϩ JANET HARDY,* ROBERT DAVIS,* YEOHOON KOH,* DON CLINE, KELLY ELDER,# RICHARD ARMSTRONG,@ HANS-PETER MARSHALL,@ THOMAS PAINTER,& ϩϩ GILLES CASTRES SAINT-MARTIN,** ROGER DEROO,** KAMAL SARABANDI,** TOBIAS GRAF, ϩϩ TOSHIO KOIKE, AND KYLE MCDONALD## *Cold Regions Research and Engineering Laboratory, Engineer Research and Development Center, U.S. Army Corps of Engineers, Hanover, New Hampshire ϩNOAA/NWS/National Operational Hydrologic Remote Sensing Center, Chanhassen, Minnesota #USDA Forest Service, Fort Collins, Colorado @University of Colorado, Boulder, Colorado &University of Utah, Salt Lake City, Utah **University of Michigan, Ann Arbor, Michigan ϩϩUniversity of Tokyo, Tokyo, Japan ##NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California (Manuscript received 12 January 2007, in final form 19 March 2008) ABSTRACT The local scale observation site (LSOS) is the smallest study site (0.8 ha) of the 2002/03 Cold Land Processes Experiment (CLPX) and is located within the Fraser mesocell study area. It was the most intensively measured site of the CLPX, and measurements here had the greatest temporal component of all CLPX sites. Measurements made at the LSOS were designed to produce a comprehensive assessment of the snow, soil, and vegetation characteristics viewed by the ground-based remote sensing instruments. The objective of the ground-based microwave remote sensing was to collect time series of active and passive microwave spectral signatures over snow, soil, and forest, which is coincident with the intensive physical characterization of these features. Ground-based remote sensing instruments included frequency modulated continuous wave (FMCW) radars operating over multiple microwave bandwidths; the Ground-Based Mi- crowave Radiometer (GBMR-7) operating at channels 18.7, 23.8, 36.5, and 89 GHz; and in 2003, an L-, C-, X- and Ku-band scatterometer radar system. -
AN1597 Longwave Radio Data Decoding Using an HC11 and an MC3371
Freescale Semiconductor, Inc... microprocessor used for decoding is the MC68HC(7)11 while microprocessor usedfordecodingisthe MC68HC(7)11 2023. and 1995 between distinguish Itisnotpossible to 2022. and thiscanbeusedtocalculate ayearintherange1995to beworked out cyclecan,however, leap–year/year–start–day data.Thepositioninthe28–year available andcannotbeuniquelydeterminedfromthe transmitted and yeartype)intoday–of–monthmonth.Theisnot dateinformation(day–of–week,weeknumber transmitted the form.Themicroprocessorconverts hexadecimal displayed whilst allincomingdatacanbedisplayedin In thisapplication,timeanddatecanbepermanently standards. Localtimevariation(e.g.BST)isalsotransmitted. provides averyaccurateclock,traceabletonational Freescale AMCU ApplicationsEngineering Topping Prepared by:P. This documentcontains informationonaproductunder development. This to thecompanyleasingitforuseinaspecificapplication. available blocks areusedcommerciallywhereeachblockis other 0isusedfortimeanddate(andfillerdata)whilethe Type purpose.There are16datablocktypes. used foradifferent countriesbuthasamuchlowerdatarateandis European with theRDSdataincludedinVHFradiosignalsmany aswelltheaudiosignal.Thishassomesimilarities data using an HC11 and Longwave an Radio MC3371 Data Decoding Figure 1showsablock diagramoftheapplication; Figure data is transmitted every minuteontheand Time The BBC’s Radio4198kHzLongwave transmittercarries The BBC’s Ltd.,EastKilbride RF AMPLIFIERDEMODULATOR FM BF199 FILTER/INT.: LM358 FILTER/INT.: AMP/DEMOD.: MC3371 LOCAL OSC.:MC74HC4060 -
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. -
World Receiver Yacht Boy 400 Pe Important Notice
WORLD RECEIVER YACHT BOY 400 PE IMPORTANT NOTICE NEED HELP? QUICK SETUP CALL OUR SHORTWAVE HOTLINE (But please read the rest of the manual later!) 1. Insert batteries or connect the included AC adaptor. If, after reading this owner’s manual, you need help learning to operate your YACHT BOY 400 PROFESSIONAL EDITION, call us toll free, Monday through Friday, 8:30 a.m. to 4:30 p.m., 2. Set the DX/LOCAL switch to DX (left side of radio). PST at: 1-800-872-2228 from the U.S. 3. Turn the SSB switch OFF (right side of radio). 1-800-637-1648 from Canada OWNER’S RECORD 4. Fully extend the telescopic antenna. This model is the GRUNDIG YACHT BOY 400 PROFES- 5. With the radio off, press and release the AM button once. SIONAL EDITION, herin after referred to as the YB400PE. The serial number is located on the sticker inside the battery compartment. Refer to this number whenever you call GRUNDIG 6. Immediately press and release the STEP button. regarding this product. “10KHz” now appears in the right side of the display, and will disappear in a few seconds. (See page 4 for more information about this procedure. 7. Turn the radio on by pressing the ON/OFF button. 1 TABLE OF CONTENTS SUBJECT PAGE GRUNDIG TOLL-FREE PHONE NUMBER………………………………………………………….............................. 1 TABLE OF CONTENTS………………………………………………………….……………………............................ 2 YOUR RADIO AT-A-GLANCE………………………………………………….……………………............................. 3 INITIAL SETUP…………………………………………………………………..……………………............................ 4 SUPPLYING POWER…………………………………………………………….……………………............................ 5 GENERAL RADIO OPERATION………………………………………………..……………………............................. 6-8 SHORTWAVE RADIO OPERATION…………………………………………...……………………............................... 9-10 STORING STATIONS INTO MEMORY………………………………………..…………………….............................. 11-12 USING CLOCK, ALARM, AND SLEEP TIMER FEATURES..............................……………………............................ -
Basics of Video
Basics of Video Yao Wang Polytechnic University, Brooklyn, NY11201 [email protected] Video Basics 1 Outline • Color perception and specification (review on your own) • Video capture and disppy(lay (review on your own ) • Analog raster video • Analog TV systems • Digital video Yao Wang, 2013 Video Basics 2 Analog Video • Video raster • Progressive vs. interlaced raster • Analog TV systems Yao Wang, 2013 Video Basics 3 Raster Scan • Real-world scene is a continuous 3-DsignalD signal (temporal, horizontal, vertical) • Analog video is stored in the raster format – Sampling in time: consecutive sets of frames • To render motion properly, >=30 frame/s is needed – Sampling in vertical direction: a frame is represented by a set of scan lines • Number of lines depends on maximum vertical frequency and viewingg, distance, 525 lines in the NTSC s ystem – Video-raster = 1-D signal consisting of scan lines from successive frames Yao Wang, 2013 Video Basics 4 Progressive and Interlaced Scans Progressive Frame Interlaced Frame Horizontal retrace Field 1 Field 2 Vertical retrace Interlaced scan is developed to provide a trade-off between temporal and vertical resolution, for a given, fixed data rate (number of line/sec). Yao Wang, 2013 Video Basics 5 Waveform and Spectrum of an Interlaced Raster Horizontal retrace Vertical retrace Vertical retrace for first field from first to second field from second to third field Blanking level Black level Ӈ Ӈ Th White level Tl T T ⌬t 2 ⌬ t (a) Խ⌿( f )Խ f 0 fl 2fl 3fl fmax (b) Yao Wang, 2013 Video Basics 6 Color