BETS-5 Issue 1 November 1, 1996
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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. -
The Market Leader in Over-The-Air Broadcasting Solutions
Connecting What’s Next The Market Leader in Over-the-Air Broadcasting Solutions GatesAir efficiently leverages broadcast spectrum to maximize performance for multichannel TV and radio services, offering the industry’s broadest portfolio to help broadcasters wirelessly deliver and monetize content. With nearly 100 years in broadcasting, GatesAir’s exclusive focus on the over-the-air market helps broadcasters optimize services today and prepare for future revenue-generating business opportunities. All research, development and innovation is driven from the company’s facilities in Mason, Ohio and supported by the long-standing manufacturing center in Quincy, Illinois. GatesAir’s turnkey solutions are built on three pillars: Content Transport, TV Transmission, and Radio Transmission. GatesAir’s globally renowned Intraplex range comprises the Transport pillar, enabling audio contribution and distribution (along with data) over IP and TDM networks. Intraplex solutions provide value for broadcasters for point-to-point (STL, remote broadcast) and multipoint (single-frequency networks, syndicated distribution) connectivity. GatesAir continues to innovate robust and reliable solutions for traditional RF STL connections that can also accommodate IP traffic. In larger transmitter networks, Simulcasting technology ensures all GatesAir transmitters are time-locked for synchronous, over-the-air content delivery. Powering over-the-air analog and digital radio/TV stations and networks worldwide with the industry’s most operationally efficient transmitters is a longtime measure of success for GatesAir. Groundbreaking innovations in low, medium and high- power transmitters reduce footprint, energy use and more to establish the industry’s lowest total cost of ownership. Support for all digital standards and convergence with mobile networks ensure futureproof systems. -
SBE Comments to FINAL AM Improvement Docket
Before the FEDERAL COMMUNICATIONS COMMISSION Washington, DC 20554 In the Matter of ) ) Revitalization of the AM Radio Service ) MB Docket No. 13-153 To: The Commission COMMENTS OF THE SOCIETY OF BROADCAST ENGINEERS, INCORPORATED 1. The Society of Broadcast Engineers, Incorporated (“SBE”)1 respectfully submits its Comments in response to portions of the Commission’s Notice of Proposed Rulemaking, 13-139, 28 FCC Rcd. 15221, released October 31, 2013 in the above-captioned proceeding (the “Notice”).2 The Notice proposes “to introduce a number of possible improvements to the … AM… radio service and the rules pertaining to AM broadcasting.” The Commission also seeks “to revitalize further the AM band by identifying ways to enhance AM broadcast quality and proposing changes to our technical rules that would enable AM stations to improve their service.” The Commission proposes to “help AM broadcasters better serve the public, thereby advancing the Commission’s fundamental goals of localism, competition, and diversity in broadcast media.” SBE applauds this effort and offers the following comments on some of the technical issues raised in this proceeding. Specifically, SBE offers its comments on four issues that will provide both immediate and long-term relief to AM broadcast licensees: 1 SBE is the national association of broadcast engineers and technical communications professionals, with more than 5,000 members worldwide. 2 The Notice of Proposed Rulemaking was published in the Federal Register November 20, 2013. See, 78 Fed. Reg. 69629. 1 -
Uwìälu @Aiswww@
Nov. 27, 1951 s. s. H|l_|_v 2,576,115 ARRANCEMENT ECR TRANSMIITINC ELECTRIC sICNALs CCCURYINC A wIDE FREQUENCY BAND CvER NARRow BAND CIRCUITS Filed Feb. 4, 1948 Nîä,_ , Emmaüzzwru www@ @waisuwìälu Patented Nov. 27, 1951 ' 2,576,115 UNITED STATES A,lnßxrlszN'r oFFlcE 2,516,115 ARRANGEMENT FOR TRANSMITTING ELEC TRIC SIGNALS OCCUPYING A WIDE FRE QUENCY BAND OVERI NARROW BAND CIR CUITS i Stuart Seymour Hill, London, England, assigner to International Standard Electric Corpora tion, New York, N. Y., a corporation of Dela Application February 4, 1948, Serial No. 6,316 In Great Britain February 7, 1947 13 Claims.` (Cl. 17H4) 2 The present invention relates to electric signal of one or more sections to the frequency range. transmission systems of the kind in which signals passed by the corresponding channel and meansl occupying a relative wide frequency band are for transmitting the frequency shifted sections. transmitted over two or more circuits each of over the respective channels, characterised in which is capable of transmitting only a relative “ this, that the frequency shifting means in thev ly narrow frequency band. case of at least one section comprises two succes The invention has its principal application to sive frequency changes, one of which employs a broadcasting circuits. fixed carrier frequency and the other a carrier It is frequently necessary to send broadcast ma frequency which is adjusted to a value deter terial to the studios by telephone line. Some 10 mined by the cut-off frequency of the correspond times special broadcast channels designed for a ing channel. -
Fcc and Am Stereo: a Deregulatory Breach of Duty
THE FCC AND AM STEREO: A DEREGULATORY BREACH OF DUTY JASON B. MEYERt The trend toward governmental deregulation of private enterprise, which began in earnest in the 1970's1 and has gathered momentum under the Reagan administration, has had a significant effect on the telecommunications industry. The Federal Communications Commis- sion (FCC) has reduced regulation of operation and maintenance log- ging2 and eliminated minimum aural transmission power require- ments.' Similarly, a major effort has been made in Congress to enact a bill deregulating broadcast programming.4 In 1984 the FCC justified eliminating or relaxing many licensing requirements on the grounds that such "actions further the Commission's goals of creating, to the maximum extent possible, an unregulated, competitive environment for t A.B. 1980, Princeton University; J.D. Candidate, 1985, University of Pennsylva- nia. The author wrote this Comment while a student at the University of Pennsylvania Law School. I See, e.g., Depository Institutions Deregulation and Monetary Control Act of 1980, Pub. L. No. 96-221, 94 Stat. 132 (codified at scattered sections of Titles 12, 15, 22 & 42 of the U.S.C.) (reducing regulatory control of banks); Airline Deregulation Act of 1978, Pub. L. No. 95-504, 92 Stat. 1705 (codified at 49 U.S.C. §§ 1300-02, 1305-08, 1324, 1341, 1371-79, 1382, 1384, 1386, 1389, 1461, 1482, 1486, 1490, 1504, 1551-52) (reducing regulatory control of airlines). I See Operating and Maintenance Logs for Broadcast and Broadcast Auxiliary Stations, 48 Fed. Reg. 38,473 (1983). ' The Commission abolished minimum aural power requirements that had previ- ously created a situation in which a station's aural range well exceeded its visual range. -
Short Wave Radio
Short Wave Radio A Working Electronic Sculpture Honoring the History of Radio Please note: This radio picks up short wave stations, but for your best satisfaction it will require a little time and attention, both to learn how to operate it and to appreciate the principles and history that it embodies. You’ll find bare-bones instructions on this page and more details inside the notebook. To turn the radio on, rotate the volume control clockwise until you hear a click, then set its dial to 3 or 4. If the radio was not already turned on, you’ll have to wait about 30 seconds for its vacuum tubes to warm up. •Put on the headphones. •Set the radio’s other controls as follows: •RF Gain: Fully clockwise. •Preselector: 1 •Tuning: 20 •Fine Tuning: 5.0 (This works like a clock, only with ten “hours” instead of 12) •Regeneration: 7 (Or advance slowly clockwise from zero until just after the point you hear a louder hiss in the headphones.) •Volume: Set to a comfortable level, usually about 4. Now, slowly adjust the TUNING control back and forth looking for squeals that indicate signals. (The shortwave broadcast band with 31 meter wavelength is located between about 10 and 30 on the dial.) You’ll should find a few unless ionospheric conditions are particularly poor on this day. Leave the TUNING control set on a loud squeal. Then slowly adjust the FINE TUNING to “zero beat.” (You’ll notice as you move the dial across a signal, it starts with a high-pitched note, moving down to a low-pitched or zero note, then back up to high pitch again. -
Prof. K Radhakrishna Rao Lecture 2 Role of Analog Signal Processing
Analog Circuits and Systems Prof. K Radhakrishna Rao Lecture 2 Role of Analog Signal Processing in Electronic Products – Part 1 1 Structure of an electronic product 2 Electronic Products o Process analog signals and digital data o This involve transmission and reception of signals and data o It is generally necessary to code signal and data to transmit over channels o Transmission can be over wires or wireless o Processing and storage are efficient in digital form o Several human interface technologies are available 3 Products considered o Radio Receiver o Modem o Cell Phone o ECG 4 Radio Receiver o AM Receiver o FM Receiver 5 Radio waves are classified as o Low frequency (LF): 30 kHz – 300 kHz, o Medium frequency (MF): 300 kHz – 3 MHz, o High frequency (HF): 3 MHz – 30 MHz, o Very high frequency (VHF): 30 MHz – 300 MHz, o Ultra high frequency (UHF): 300 MHz – 3 GHz, o Super high frequency (SHF): 3 GHz – 30 GHz, o Extremely high frequency (EHF): 30 GHz to 300 GHz. 6 Radio broadcasting o one-way wireless transmission over radio waves to reach a wide audience o takes place in MF (300 kHz – 3 MHz), HF (3 MHz – 30 MHz) and VHF (30 MHz – 300 MHz) regions 7 Major modes of radio broadcasting o Sine wave (single tone) represented by Vtp sin(ωφ+ ) PM (Analog) where φ = phase in radians PSK (Digital) QPSK( Digital) FM (Analog) ω = frequency in rad/sec FSK (Digital) AM, DSB (Analog) V = peak magnitude in volts p ASK (Digital) 8 AM broadcasting o Amplitude of the carrier signal is varied in response to the amplitude of the signal to be transmitted o Amplitude modulation is done by a unit called mixer (nothing but a multiplier) which produces an output output=+( Vpc V pm sinωω m t )sin c t Vpm where ωm is the modulating frequency = m is known as the Vpc ω is the carrier frequency c modulation index. -
Program and System Information Protocol Implementation Guidelines for Broadcasters
ATSC Recommended Practice: Program and System Information Protocol Implementation Guidelines for Broadcasters Document A/69:2009, 25 December 2009 Advanced Television Systems Committee, Inc. 1776 K Street, N.W., Suite 200 Washington, D.C. 20006 Advanced Television Systems Committee Document A/69:2009 The Advanced Television Systems Committee, Inc., is an international, non-profit organization developing voluntary standards for digital television. The ATSC member organizations represent the broadcast, broadcast equipment, motion picture, consumer electronics, computer, cable, satellite, and semiconductor industries. Specifically, ATSC is working to coordinate television standards among different communications media focusing on digital television, interactive systems, and broadband multimedia communications. ATSC is also developing digital television implementation strategies and presenting educational seminars on the ATSC standards. ATSC was formed in 1982 by the member organizations of the Joint Committee on InterSociety Coordination (JCIC): the Electronic Industries Association (EIA), the Institute of Electrical and Electronic Engineers (IEEE), the National Association of Broadcasters (NAB), the National Cable Telecommunications Association (NCTA), and the Society of Motion Picture and Television Engineers (SMPTE). Currently, there are approximately 140 members representing the broadcast, broadcast equipment, motion picture, consumer electronics, computer, cable, satellite, and semiconductor industries. ATSC Digital TV Standards include -
RADIO's DIGITAL DILEMMA: BROADCASTING in the 21St
RADIO’S DIGITAL DILEMMA: BROADCASTING IN THE 21st CENTURY BY JOHN NATHAN ANDERSON DISSERTATION Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Communications in the Graduate College of the University of Illinois at Urbana-Champaign, 2011 Urbana, Illinois Doctoral Committee: Professor John C. Nerone, Chair and Director of Research Associate Professor Michelle Renee Nelson Associate Professor Christian Edward Sandvig Professor Daniel Toby Schiller ii ABSTRACT The interaction of policy and technological development in the era of “convergence” is messy and fraught with contradictions. The best expression of this condition is found in the story behind the development and proliferation of digital audio broadcasting (DAB). Radio is the last of the traditional mass media to navigate the convergence phenomenon; convergence itself has an inherently disruptive effect on traditional media forms. However, in the case of radio, this disruption is mostly self-induced through the cultivation of communications policies which thwart innovation. A dramaturgical analysis of digital radio’s technological and policy development reveals that the industry’s preferred mode of navigating the convergence phenomenon is not designed to provide the medium with a realistically useful path into a 21st century convergent media environment. Instead, the diffusion of “HD Radio” is a blocking mechanism proffered to impede new competition in the terrestrial radio space. HD Radio has several critical shortfalls: it causes interference and degradation to existing analog radio signals; does not have the capability to actually advance the utility of radio beyond extant quality/performance metrics; and is a wholly proprietary technology from transmission to reception. -
Kidsdictionary.Pdf
Access Charges: This is a fee charged by local phone companies for use of their networks. Amplitude Modulation (AM) that's the "AM" Band on your Radio: A signaling method that varies the amplitude of the carrier frequencies to send information. The carrier frequency would be like 910 (kHz) AM on your AM dial. Your radio antenna receives this signal and then decodes it and plays the song. Analog Signal: A signaling method that modifies the frequency by amplifying the strength of the signal or varying the frequency of a radio transmission to convey information. Bandwidth The amount of data passing through a connection over a given time. It is usually measured in bps (bits-per- second) or Mbps. Broadband Broadband refers to telecommunication in which a wide band of frequencies is available to transmit information. More services can be provided through broadband in the same way as more lanes on a highway allow more cars to travel on it at the same time. Broadcast To transmit (a radio or television program) for public or general use. In other words, send out or communicate, especially by radio or television. Cable A strong, large-diameter, heavy steel or fiber rope. The word history of cable derives from Middle English, from Old North French, from Late Latin capulum, lasso, from Latin capere, meaning to seize. Calling Party Pays A billing method in which a wireless phone caller pays only for making calls and not for receiving them. The standard American billing system requires wireless phone customers to pay for all calls made and received on a wireless phone. -
750 Review Insert
The Eton Elite 750 is much more than just a fancy-looking boom-box shortwave receiver, reports WB6NOA, who listened to all it has to offer, including longwave, shortwave, the AM and FM broadcast bands, and the VHF air band. CQ Reviews: Eton Elite 750 Shortwave Receiver BY GORDON WEST,* WB6NOA s ham operators, we know not to pre-judge a radio by just how it Alooks, or how many buttons and meters it may have on the face. Like many of you, I have a collection of no- name bargain mail-order portable shortwave (SW) receivers, but few can hold a candle to those from name-brand manufacturers. Now, this monster- sized Eton receiver is hitting the mar- ket in grand style. The Eton Elite 750 is major-sized multi-mode receiver, fun for a radio enthusiast wanting to tune in what’s out there from 100 kHz to 30 MHz, plus the AM and FM broadcast bands and AM air-band reception. The Eton name may be unfamiliar to you, and the 750 looks a lot like a pre- vious radio from Grundig. Actually, the two companies have a relationship that spans 35 years, as explained by Eton CEO and Chairman Esmail Amid- The large speaker makes the Eton Elite 750 a great poolside or beach enter- Hozour. “From our initial partnership tainment radio, too! Plenty of audio output, enough to also power a personal with Max Grundig in 1979, Eton has car- music player that can plug in. ried on Grundig’s 75+ year legacy in developing the best-in-class world band we bring new and exciting shortwave non-directional radio beacons (NDBs), radios.” Esmail continued, “Eton’s dedi- products to the market each year.” Navtex, 630-meter ham radio CW bea- cation to design and innovation spans cons, and various government stations partnerships with Drake to ensure high- Exploring the Elite 750 lurking down here. -
Digital Terrestrial Radio for Australia
Parliament of Australia Department of Parliamentary Services Parliamentary Library Information, analysis and advice for the Parliament RESEARCH PAPER www.aph.gov.au/library 19 December, no. 18, 2008–09, ISSN 1834-9854 Going digital—digital terrestrial radio for Australia Dr Rhonda Jolly Social Policy Section Executive summary th • Since the early 20 century radio has been an important source of information and entertainment for people of various ages and backgrounds. • Almost every Australian home and car has at least one radio and most Australians listen to radio regularly. • The introduction of new radio technology—digital terrestrial radio—which can deliver a better listening experience for audiences, therefore has the potential to influence people’s lives significantly. • Digital radio in a variety of technological formats has been established in a number of countries for some years, but it is expected only to become a reality in Australia sometime in 2009. • Unlike the idea of digital television however, digital radio has not fully captured the imagination of audiences and in some markets there are suggestions that it is no longer relevant. • This paper provides a simple explanation of the major digital radio standards and a brief history of their development. It particularly examines the standard chosen for Australia, the Eureka 147 standard (known also as Digital Audio Broadcasting or DAB). • The paper also traces the development of digital radio policy in Australia and considers issues which may affect the future of the technology. Contents Introduction ................................................................................................................................. 1 Radio basics: AM and FM radio ................................................................................................. 3 How do AM and FM work? ................................................................................................... 3 How AM radio works .......................................................................................................