A Technical RADIO and ELECTRONICS RESEARCH
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Technical Details of the Elliott 152 and 153
Appendix 1 Technical Details of the Elliott 152 and 153 Introduction The Elliott 152 computer was part of the Admiralty’s MRS5 (medium range system 5) naval gunnery project, described in Chap. 2. The Elliott 153 computer, also known as the D/F (direction-finding) computer, was built for GCHQ and the Admiralty as described in Chap. 3. The information in this appendix is intended to supplement the overall descriptions of the machines as given in Chaps. 2 and 3. A1.1 The Elliott 152 Work on the MRS5 contract at Borehamwood began in October 1946 and was essen- tially finished in 1950. Novel target-tracking radar was at the heart of the project, the radar being synchronized to the computer’s clock. In his enthusiasm for perfecting the radar technology, John Coales seems to have spent little time on what we would now call an overall systems design. When Harry Carpenter joined the staff of the Computing Division at Borehamwood on 1 January 1949, he recalls that nobody had yet defined the way in which the control program, running on the 152 computer, would interface with guns and radar. Furthermore, nobody yet appeared to be working on the computational algorithms necessary for three-dimensional trajectory predic- tion. As for the guns that the MRS5 system was intended to control, not even the basic ballistics parameters seemed to be known with any accuracy at Borehamwood [1, 2]. A1.1.1 Communication and Data-Rate The physical separation, between radar in the Borehamwood car park and digital computer in the laboratory, necessitated an interconnecting cable of about 150 m in length. -
A 'T97- 7- Art97- 3
June 22, 1965 SHINTAROOSHIMA ETAL 3,191,053 SIGN DETECTING SYSTEM Fillied Aug. 19, 1960 6 Sheets-Sheet I A 't97- 7- Art97- 3. fend za June 22, 1965 sHINTARO osHIMA ETAL 3,191,053 SIGN DETECTING SYSTEM Filed Aug. 19, 1960 6 Sheets-Sheet 2 Az7-2- ...C I / I I,/ III Asg - F - - June 22, 1965 SHINTARO OSHIMA ETAL 3,191,053 SIGN DETECTING SYSTEM Filled Aug. 19, 1960 6 Sheets-Sheet 3 Zz7- 6 - A - G7 - 9 e2f ASA, a A. A1 A. 62. APPS C AMe O) C As if Asa Af A. O) Z/2 Me O) At(6) A2 ; : : : A2 : WarfO) 72AA Merg 3.N. y eaa June 22, 1965 SHINTARO OSHIMA ETAL 3,191,053 SIGN DETECTING SYSTEM Filed Aug. 19, 1960 6 Sheets-Sheet 4 Z'67-72. A 't:9-73 - As? A. Ca -- G, Ay + \ 42 a .2A A 7 aia 2 A/ A1 Az/4A, Og /We AZeO A.O. We A4 2% O A7. June 22, 1965 SHINTARO OSHIMA ETAL 3,191,053 SIGN DETECTING SYSTEM Filed Aug. 19, l960 6 Sheets-Sheet 5 (o) June 22, 1965 SHINTARO OSHIMA ETAL 3,191,053 SIGN DETECTING SYSTEM Fiied Aug. 19, 1960 6 Sheets-Sheet 6 3,191,053 United States Patent Office Patiented June 22, 1965 2 FIG. 4 is a wave diagram for showing an example of 3,191,053 control time chart for describing the operating principle SIGN DETECTING SYSTEM of the system of the present invention; Shintaro Oshima, Tokyo-to, Hajime Enomoto, ichikawa FIGS. 5 (A) and (B) are characteristic curves for de shi, and Shiyoji Watanabe and Yasuo Koseki, Tokyo-to, 5 scribing an operation principle of the system of the Japan, assignors to Kokusai Denshin Denwa Kablishiki present invention; Kaisha, Tokyo-to, Japan FIGS. -
Radio Communications in the Digital Age
Radio Communications In the Digital Age Volume 1 HF TECHNOLOGY Edition 2 First Edition: September 1996 Second Edition: October 2005 © Harris Corporation 2005 All rights reserved Library of Congress Catalog Card Number: 96-94476 Harris Corporation, RF Communications Division Radio Communications in the Digital Age Volume One: HF Technology, Edition 2 Printed in USA © 10/05 R.O. 10K B1006A All Harris RF Communications products and systems included herein are registered trademarks of the Harris Corporation. TABLE OF CONTENTS INTRODUCTION...............................................................................1 CHAPTER 1 PRINCIPLES OF RADIO COMMUNICATIONS .....................................6 CHAPTER 2 THE IONOSPHERE AND HF RADIO PROPAGATION..........................16 CHAPTER 3 ELEMENTS IN AN HF RADIO ..........................................................24 CHAPTER 4 NOISE AND INTERFERENCE............................................................36 CHAPTER 5 HF MODEMS .................................................................................40 CHAPTER 6 AUTOMATIC LINK ESTABLISHMENT (ALE) TECHNOLOGY...............48 CHAPTER 7 DIGITAL VOICE ..............................................................................55 CHAPTER 8 DATA SYSTEMS .............................................................................59 CHAPTER 9 SECURING COMMUNICATIONS.....................................................71 CHAPTER 10 FUTURE DIRECTIONS .....................................................................77 APPENDIX A STANDARDS -
Analysis of Outdoor and Indoor Propagation at 15 Ghz and Millimeter Wave Frequencies in Microcellular Environment
Advances in Science, Technology and Engineering Systems Journal Vol. 3, No. 1, 160-167 (2018) ASTESJ www.astesj.com ISSN: 2415-6698 Special issue on Advancement in Engineering Technology Analysis of Outdoor and Indoor Propagation at 15 GHz and Millimeter Wave Frequencies in Microcellular Environment Muhammad Usman Sheikh*, Jukka Lempiainen Tampere University of Technology, Department of Electronics and Communications Engineering, Finland. A R T I C L E I N F O A B S T R A C T Article history: The main target of this article is to perform the multidimensional analysis of multipath Received: 26 November, 2017 propagation in an indoor and outdoor environment at higher frequencies i.e. 15 GHz, 28 Accepted: 07 January, 2018 GHz and 60 GHz, using “sAGA” a 3D ray tracing tool. A real world outdoor Line of Sight Online: 30 January, 2018 (LOS) microcellular environment from the Yokusuka city of Japan is considered for the analysis. The simulation data acquired from the 3D ray tracing tool includes the received Keywords: signal strength, power angular spectrum and the power delay profile. The different Multipath propagation propagation mechanisms were closely analyzed. The simulation results show the difference Microcellular of propagation in indoor and outdoor environment at higher frequencies and draw a special 3D ray tracing attention on the impact of diffuse scattering at 28 GHz and 60 GHz. In a simple outdoor System performance microcellular environment with a valid LOS link between the transmitter and a receiver, 5G the mean received signal at 28 GHz and 60 GHz was found around 5.7 dB and 13 dB Millimeter wave frequencies inferior in comparison with signal level at 15 GHz. -
Magnetic Amplifiers & Saturable Reactors
Magnetic amplifiers & Saturable reactors Ricciarelli Fabrizio 01/01/2016 Magnetic amplifiers and saturable reactors Summary SECTION I.......................................................................................................................................................... 2 What are the saturable reactors .................................................................................................................. 2 SECTION II ......................................................................................................................................................... 3 Types of reactors .......................................................................................................................................... 3 Saturable reactors .................................................................................................................................... 4 Linear reactors .......................................................................................................................................... 4 Control modules ....................................................................................................................................... 4 SECTION III ........................................................................................................................................................ 5 History ......................................................................................................................................................... -
Noise and Multipath Characteristics of Power Line Communication Channels
University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School 3-30-2010 Noise and Multipath Characteristics of Power Line Communication Channels Hasan Basri Çelebi University of South Florida Follow this and additional works at: https://scholarcommons.usf.edu/etd Part of the American Studies Commons Scholar Commons Citation Çelebi, Hasan Basri, "Noise and Multipath Characteristics of Power Line Communication Channels" (2010). Graduate Theses and Dissertations. https://scholarcommons.usf.edu/etd/1594 This Thesis is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Noise and Multipath Characteristics of Power Line Communication Channels by Hasan Basri C»elebi A thesis submitted in partial ful¯llment of the requirements for the degree of Master of Science in Electrical Engineering Department of Electrical Engineering College of Engineering University of South Florida Major Professor: HÄuseyinArslan, Ph.D. Chris Ferekides, Ph.D. Paris Wiley, Ph.D. Date of Approval: Mar 30, 2010 Keywords: Power line communication, noise, cyclostationarity, multipath, impedance, attenuation °c Copyright 2010, Hasan Basri C»elebi DEDICATION This thesis is dedicated to my fianc¶eeand my parents for their constant love and support. ACKNOWLEDGEMENTS First, I would like to thank my advisor Dr. HÄuseyinArslan for his guidance, encour- agement, and continuous support throughout my M.Sc. studies. It has been a privilege to have the opportunity to do research as a member of Dr. Arslan's research group. -
The Magnetic Amplifier a Lost Technology of the 1950S Anyone Can Build It! ■ by George Trinkaus
Trinkaus.qxd 1/11/2006 1:04 PM Page 68 The Magnetic Amplifier A Lost Technology of the 1950s Anyone can build it! ■ by George Trinkaus ost folks believe that first came the vacuum tube and right on its heels came its successor, the transistor — an historical fact, correct? Not really. Another competitive control technology developed by US and Nazi engineers came in between. It was the magnetic amplifier. Rugged, dependable, EMP- proof, and capable of handling greater electrical powers than either transistor or tube, the magnetic amplifier is a simple device that can be built by anyone. By the 1950s, the magnetic amplifier M was not just an experimental dream languishing in some inventor’s notebook. Nor was this ingenious technology sitting unexploited in patent archives. The mag amp was in manufac- ture in a number of versions and had a clique of boosters, including many electronics engineers, especially within the US Navy. ■ Home-built Mag Amp. 68 February 2006 Trinkaus.qxd 1/11/2006 1:05 PM Page 69 ■ FIGURE 1. Principle of Operation. ■ FIGURE 2. Saturable Reactor. The mag amp is an American that’s the definition of an “amplifier.” core’s permeability (its receptivity to invention and has been used in heavy A mag amp can be put in series magnetism) can be varied by degrees, electrical machinery regulators since with any circuit carrying an alternat- thus controlling a larger AC flow. 1900. In the 1940s, the Germans took ing current and control that flow. No Fully energized, the control coil the American’s relatively crude device, external power supply is required to can reduce the permeability of the assigned their best scientists, invested run the device. -
Lawrence Berkeley National Laboratory Recent Work
Lawrence Berkeley National Laboratory Recent Work Title EXPERIMENTAL AND EXTERNAL-PROTON-BEAM MAGNET POWER-SUPPLY SYSTEMS AT THE BEVATRON Permalink https://escholarship.org/uc/item/05r5c6gp Author Jackson, Leslie T. Publication Date 1965-02-11 eScholarship.org Powered by the California Digital Library University of California UCRL-11793 University of California Er'nest 0. lawrence Radiation Laboratory EXPERIMENTAL AND EXTERNAL-PROTON-BEAM MAGNET POWER-SUPPLY SYSTEMS AT THE BEVATRON TWO-WEEK LOAN COPY This is a Library Circulating Copy which may be borrowed for two weeks. For a personal retention copy, call Tech. Info. Division, Ext. 5545 ·Berkeley, California DISCLAIMER This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor the Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, or the Regents of the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof or the Regents of the University of California. -
Approved for Public Release. Case 06-1104
APPROVED FOR PUBLIC RELEASE. CASE 06-1104. Engineering Bote E-477 Page 1 of 13 Digital Computer laboratory Massachusetts Institute of Technology Cambridge, Massachusetts SUBJECT: MAGNETIC AND DIEIECTBIC AMPLIFIERS To: Jay W. Forrester From: Dudley A. Buck Date: August 28, 1952 Abstract: This paper was prepared at the request of Professor Arthur B. von Eippel for presentation at a summer symposium on the Theory and. Applications of Dielectric Materials. September 3-12, 1952, at the Massachusetts Institute of Technology* A. INTBODUCTIOH The prime motivation behind recent magnetic and dielectric amplifier research is the quest for amplifiers which are more reliable and more rugged than vacuum-tube amplifiers. Amplifiers of increased reliability and rugged- ness are needed in military and industrial control circuits, in communication circuits, and in information-handling machines* Before describing how a piece of iron alloy or a thin sheet of barium titanate can act as an amplifier, let us briefly consider amplifiers in general. The term amplifier here refers to a power amplifier* Power amplifiers are three terminal-pair devices (Fig* 1)* One terminal pair is associated with the input, or signal to be amplified; one terminal pair is associated with the output, or load; and the third terminal pair is associated with the power supply. The power supply contains no information, that is, it contains no meaningful fluctuating component that is to be amplified. The power supply can be a direct voltage, a sinusoidal voltage, a sequence of pulses, or any other waveform for which the amplifier is designed to operate* Vacuum-tube and transistor amplifiers normally use direct voltage power supply, while magnetic and dielectric amplifiers, by their very nature, must use alternating current or pulsed power supplies* Power amplification, or power gain, may be defined as the average output power divided by the average input power, without reference to the average power delivered by the power supply. -
Influence of Terrain on Multipath Propagation of Fm Signal
Journal of ELECTRICAL ENGINEERING, VOL. 56, NO. 5-6, 2005, 113–120 INFLUENCE OF TERRAIN ON MULTIPATH PROPAGATION OF FM SIGNAL J´an Klima ∗ — Mari´an Moˇzucha ∗∗ FM signal propagating through the troposphere interacts with the terrain as a reflecting plane. These reflected signals are not included into calculations and predictions of the field strength. The reason is simple — it is too difficult for processing, and demanding high quality data. For recent capabilities of computers and resolution level of digital terrain models this is not an irresolvable problem. In the report the authors show a practical demonstration how to include the reflected FM signals into the field strength calculations as well as the comparison with standard methods of field strength predictions. K e y w o r d s: digital terrain model (DTM), reflections, diffraction, multipath propagation 1 INTRODUCTION Here GRF represents a set of points of the terrain, z is the height in a point located in coordinates [x,y], A digital terrain model, as a discrete field of repre- KN F M is the curvature of the terrain as it is seen from sentative and positionally expressed points of the terrain the transmitter, FF M is the form, γF M is the slope, AF M and its approximation equations securing its continuity is the aspect, and δexp F M is irradiation — all from the [8] can serve, besides many other tasks, as a tool for lo- direction of the transmitter. cating, testing and calculating the reflecting planes for We will come from the known fact that the received propagating FM signals. -
An1007 L6561
AN1007 ® APPLICATION NOTE L6561 - BASED SWITCHER REPLACES MAG AMPS IN SILVER BOXES by Claudio Adragna Mag amps (a contraction of "Magnetic Amplifier") are widely used in multi-output switching power supplies to get auxiliary regulated power rails. However, they are expensive, bulky, and require a high level of design expertise. ST’s L6561, an 8-pin Transition Mode PFC (Power Factor Corrector) controller, is surprisingly suit- able for implementing a switch-mode architecture as an alternative to mag amps. Much better per- formance, a dramatic reduction of parts count, cost and design effort are the benefits of such an ap- proach. Drawbacks? None. And once more the L6561 turns out to be a really versatile device. Introduction Desktop computer power supplies provide two or more low-voltage, high-current, isolated power rails, typically a 5V rail and a 12V rail. More an more often, it also provides a 3.3V auxiliary rail with high-cur- rent capability. The power is generated by an off-line forward switching converter (inside the so-called "silver box") that regulates only one power rail through an isolated feedback loop. The other power rails are usually post- regulated to meet the specifications on the output voltage tolerance and regulation. A typical architecture is shown in fig. 1. Figure 1. Typical architecture of an SMPS for desktop computer ("silver box"). (ISOLATED) FEEDBACK MAIN RECTIFIER FILTER OUTPUT DC Input PWM CONTROLLER & POWER SWITCH RECTIFIER MAG AMP + REGULATOR FILTER AUXILIARY DC OUTPUTS MAIN TRANSFORMER RECTIFIER LINEAR + REGULATOR FILTER Many power supply manufacturers use magnetic amplifiers (in short, "mag amps") to achieve secondary post-regulation. -
Mobile Tv: a Technical and Economic Comparison Of
MOBILE TV: A TECHNICAL AND ECONOMIC COMPARISON OF BROADCAST, MULTICAST AND UNICAST ALTERNATIVES AND THE IMPLICATIONS FOR CABLE Michael Eagles, UPC Broadband Tim Burke, Liberty Global Inc. Abstract We provide a toolkit for the MSO to assess the technical options and the economics of each. The growth of mobile user terminals suitable for multi-media consumption, combined Mobile TV is not a "one-size-fits-all" with emerging mobile multi-media applications opportunity; the implications for cable depend on and the increasing capacities of wireless several factors including regional and regulatory technology, provide a case for understanding variations and the competitive situation. facilities-based mobile broadcast, multicast and unicast technologies as a complement to fixed In this paper, we consider the drivers for mobile line broadcast video. TV, compare the mobile TV alternatives and assess the mobile TV business model. In developing a view of mobile TV as a compliment to cable broadcast video; this paper EVALUATING THE DRIVERS FOR MOBILE considers the drivers for future facilities-based TV mobile TV technology, alternative mobile TV distribution platforms, and, compares the Technology drivers for adoption of facilities- economics for the delivery of mobile TV based mobile TV that will be considered include: services. Innovation in mobile TV user terminals - the We develop a taxonomy to compare the feature evolution and growth in mobile TV alternatives, and explore broadcast technologies user terminals, availability of chipsets and such as DVB-H, DVH-SH and MediaFLO, handsets, and compression algorithms, multicast technologies such as out-of-band and Availability of spectrum - the state of mobile in-band MBMS, and unicast or streaming broadcast standardization, licensing and platforms.