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Frequency Plan, 2004
BOTSWANA RADIO FREQUENCY PLAN, 2004 . Botswana Radio Frequency Plan, 2004 Published on 16 April 2004. TABLE OF CONTENTS Part 1 PRELIMINARY 1. Introduction. 2. Definitions. 3. Interpretation of Table of Frequency Allocations. Part II TABLE OF FREQUENCY ALLOCATIONS 4. Table of Frequency Allocations. 5. ITU Radio Regulations Footnotes National Radio Frequency Plan 2004 Page 1 BOTSWANA RADIO FREQUENCY PLAN, 2004 . PART 1 - PRELIMINARY 1. Introduction The basis for the Botswana Radio Frequency Band Plan is Section 43 of the Telecommunications Act, 1996 [No. 15 of 1996] and Article 5 of the International Telecommunication Union (ITU) Radio Regulations. The ITU Radio Regulations are annexed to the ITU Convention and are revised by the ITU World Radiocommunication Conference, normally held every three years. The Botswana frequency allocations are broadly in consonance with the ITU requirements for Region 1, within which Botswana falls under 2. Definitions In these regulations, unless the context otherwise requires, “Act” refers to the Telecommunications Act No. 15 of 1996. “Administration” means a government or public authority of a country that is responsible for giving effect to the obligations of the country as a member of International Telecommunications Union (ITU). Botswana Telecommunication Authority (BTA) is the Botswana administration. “Additional Allocation” means an allocation, in the form of Footnote, which is added in this area or in this country to the services or services which are indicated in Table of Frequency allocation. “Aeronautical Mobile Service” a mobile service between aeronautical stations and aircraft stations, or between aircraft stations, in which survival craft stations may participate; emergency position-indicating radiobeacon stations may also participate in this service on designated distress and emergency frequencies. -
Comparing Four Methods of Correcting GPS Data: DGPS, WAAS, L-Band, and Postprocessing Dick Karsky, Project Leader
United States Department of Agriculture Engineering Forest Service Technology & Development Program July 2004 0471-2307–MTDC 2200/2300/2400/3400/5100/5300/5400/ 6700/7100 Comparing Four Methods of Correcting GPS Data: DGPS, WAAS, L-Band, and Postprocessing Dick Karsky, Project Leader he global positioning system (GPS) of satellites DGPS Beacon Corrections allows persons with standard GPS receivers to know where they are with an accuracy of 5 meters The U.S. Coast Guard has installed two control centers Tor so. When more precise locations are needed, and more than 60 beacon stations along the coastal errors (table 1) in GPS data must be corrected. A waterways and in the interior United States to transmit number of ways of correcting GPS data have been DGPS correction data that can improve GPS accuracy. developed. Some can correct the data in realtime The beacon stations use marine radio beacon fre- (differential GPS and the wide area augmentation quencies to transmit correction data to the remote GPS system). Others apply the corrections after the GPS receiver. The correction data typically provides 1- to data has been collected (postprocessing). 5-meter accuracy in real time. In theory, all methods of correction should yield similar In principle, this process is quite simple. A GPS receiver results. However, because of the location of different normally calculates its position by measuring the time it reference stations, and the equipment used at those takes for a signal from a satellite to reach its position. stations, the different methods do produce different Because the GPS receiver knows exactly where results. -
963837070-MIT.Pdf
Characterization of Redundant UHF Communication Systems for CubeSats by Stephen J. Shea Jr. B.S. Astronautical Engineering United States Air Force Academy, 2014 SUBMITTED TO THE DEPARTMENT OF AERONATICS AND ASTRONAUTICS IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN AERONAUTICS AND ASTRONAUTICS AT THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY JUNE 2016 C 2016 Massachusetts Institute of Technology. All rights reserved. Signature of Author: Signature redacted Department of AfironauticWoUnd XeronaTtics May 19, 2016 Certified by: _____Signature redacted KerCahoy Assistant Professor of Aeronautics and Astronautics Thesis Supervisor Accepted by: Signature redacted / Paulo C. Lozano Associate Professor of Aerofautics and Astronautics Chair, Graduate Program Committee MASSACHUSETTS INSTITUTE OF TECHNOLOGY JUN 2 8 2016 LIBRARIES ARCHIVES The opinions expressed in this thesis are the author's own and do not reflect the view of the United States Air Force, the Department of Defense, or the United States government. 2 Characterization of Redundant UHF Communication Systems for CubeSats by Stephen Joseph Shea, Jr Submitted to the Department of Aeronautics and Astronautics on , in partial fulfillment of the requirements for the degree of Master of Science in Aeronautics and Astronautics Abstract In this thesis we describe the process of determining the likelihood of two different Ultra High Frequency (UHF) radios damaging each other on orbit, determining how to mitigate the damage, and testing to prove the radios are protected by the mitigation. The example case is the Microwave Radiometer Technology Acceleration (MiRaTA) CubeSat. We conducted a trade study over three available radio architectures: primary radio and a beacon, high speed primary and low speed backup radios, and two fully capable radios. -
Imet-4 Radiosonde 403 Mhz GPS Synoptic
iMet-4 Radiosonde 403 MHz GPS Synoptic Technical Data Sheet Temperature and Humidity Radiosonde Data Transmission The iMet-4 measures air temperature with a The iMet-4 radiosonde can transmit to an small glass bead thermistor. Its small size effective range of over 250 km*. minimizes effects caused by long and short- wave radiation and ensures fast response times. A 6 kHz peak-to-peak FM transmission maximizes efficiency and makes more channels The humidity sensor is a thin-film capacitive available for operational use. Seven frequency polymer that responds directly to relative selections are pre-programmed - with custom humidity. The sensor incorporates a temperature programming available. sensor to minimize errors caused by solar heating. Calibration Pressure and Height The iMet-4’s temperature and humidity sensors are calibrated using NIST traceable references to As recommended by GRUAN3, the iMet-4 is yield the highest data quality. equipped with a pressure sensor to calculate height at lower levels in the atmosphere. Once Benefits the radiosonde reaches the optimal height, pressure is derived using GPS altitude combined • Superior PTU performance with temperature and humidity data. • Lightweight, compact design • No assembly or recalibration required The pressure sensor facilitates the use of the • GRUAN3 qualified (pending) sonde in field campaigns where a calibrated • Status LED indicates transmit frequency barometer is not available to establish an selection and 3-D GPS solution accurate ground observation for GPS-derived • Simple one-button user interface pressure. For synoptic use, the sensor is bias adjusted at ground level. Winds Data from the radiosonde's GPS receiver is used to calculate wind speed and direction. -
Comparison Between GPS Radio Occultation and Radiosonde Sounding Data
Comparison Between GPS Radio Occultation and Radiosonde Sounding Data Dione Rossiter Academic Affiliation, Fall 2003: Senior University of California, Berkeley SOARS® Summer 2003 Science Research Mentors: Christian Rocken, Bill Kuo, and Bill Schreiner Writing and Communications Mentor: David Gochis Community Mentor: Annette Lampert Peer Mentor: Pauline Datulayta ABSTRACT Global Positioning System (GPS) Radio Occultation (RO) is a new technique for obtaining profiles of atmospheric properties, specifically: refractivity, temperature, pressure, water vapor pressure in the neutral atmosphere, and electron density in the ionosphere. The data received from GPS RO contribute significant amounts of information to a range of fields including meteorology, climate, ionospheric research, geodesy, and gravity. Low-Earth orbiting satellites, equipped with a GPS receiver, track GPS radio signals as they set or rise behind the Earth. Since GPS signals are refracted (delayed and bent) by the Earth's atmosphere, these data are used to infer information about atmospheric refractivity. Before the GPS RO data are used for research and operations, it is essential to assess their accuracy. Therefore, this research provided quantitative estimates of the accuracy of GPS RO when compared with measurements of known accuracy. Profile statistics (mean, standard deviation, standard error) were computed as a function of altitude to quantify the errors. Comparing RO data with nearby (300km; 2hr) radiosonde data yielded small mean error for all of the statistical plots generated, affirming that the RO technique is accurate for measuring atmospheric properties. Comparison of RO data with sounding data from different radiosonde systems showed that the RO technique was of high enough accuracy to differentiate differences in performance of various types of radiosonde systems. -
GPS-Based Measurement of Height and Pressure with Vaisala Radiosonde RS41
GPS-Based Measurement of Height and Pressure with Vaisala Radiosonde RS41 WHITE PAPER Table of Contents CHAPTER 1 Introduction ................................................................................................................................................. 4 Executive Summary of Measurement Performance ............................................................................. 5 CHAPTER 2 GPS Technology in the Vaisala Radiosonde RS41 ........................................................................................... 6 Radiosonde GPS Receiver .................................................................................................................. 6 Local GPS Receiver .......................................................................................................................... 6 Calculation Algorithms ..................................................................................................................... 6 CHAPTER 3 GPS-Based Measurement Methods ............................................................................................................... 7 Height Measurement ......................................................................................................................... 7 Pressure Measurement ..................................................................................................................... 7 Measurement Accuracy..................................................................................................................... 8 CHAPTER -
ESSENTIALS of METEOROLOGY (7Th Ed.) GLOSSARY
ESSENTIALS OF METEOROLOGY (7th ed.) GLOSSARY Chapter 1 Aerosols Tiny suspended solid particles (dust, smoke, etc.) or liquid droplets that enter the atmosphere from either natural or human (anthropogenic) sources, such as the burning of fossil fuels. Sulfur-containing fossil fuels, such as coal, produce sulfate aerosols. Air density The ratio of the mass of a substance to the volume occupied by it. Air density is usually expressed as g/cm3 or kg/m3. Also See Density. Air pressure The pressure exerted by the mass of air above a given point, usually expressed in millibars (mb), inches of (atmospheric mercury (Hg) or in hectopascals (hPa). pressure) Atmosphere The envelope of gases that surround a planet and are held to it by the planet's gravitational attraction. The earth's atmosphere is mainly nitrogen and oxygen. Carbon dioxide (CO2) A colorless, odorless gas whose concentration is about 0.039 percent (390 ppm) in a volume of air near sea level. It is a selective absorber of infrared radiation and, consequently, it is important in the earth's atmospheric greenhouse effect. Solid CO2 is called dry ice. Climate The accumulation of daily and seasonal weather events over a long period of time. Front The transition zone between two distinct air masses. Hurricane A tropical cyclone having winds in excess of 64 knots (74 mi/hr). Ionosphere An electrified region of the upper atmosphere where fairly large concentrations of ions and free electrons exist. Lapse rate The rate at which an atmospheric variable (usually temperature) decreases with height. (See Environmental lapse rate.) Mesosphere The atmospheric layer between the stratosphere and the thermosphere. -
The Impact of Dropsonde and Extra Radiosonde Observations During NAWDEX in Autumn 2016
FEBRUARY 2020 S C H I N D L E R E T A L . 809 The Impact of Dropsonde and Extra Radiosonde Observations during NAWDEX in Autumn 2016 MATTHIAS SCHINDLER Meteorologisches Institut, Ludwig-Maximilians-Universitat,€ Munich, Germany MARTIN WEISSMANN Hans-Ertel Centre for Weather Research, Deutscher Wetterdienst, Munich, Germany, and Institut fur€ Meteorologie und Geophysik, Universitat€ Wien, Vienna, Austria ANDREAS SCHÄFLER Institut fur€ Physik der Atmosphare,€ Deutsches Zentrum fur€ Luft- und Raumfahrt, Oberpfaffenhofen, Germany GABOR RADNOTI European Centre for Medium-Range Weather Forecasts, Reading, United Kingdom (Manuscript received 2 May 2019, in final form 18 November 2019) ABSTRACT Dropsonde observations from three research aircraft in the North Atlantic region, as well as several hundred additionally launched radiosondes over Canada and Europe, were collected during the international North Atlantic Waveguide and Downstream Impact Experiment (NAWDEX) in autumn 2016. In addition, over 1000 dropsondes were deployed during NOAA’s Sensing Hazards with Operational Unmanned Technology (SHOUT) and Reconnaissance missions in the west Atlantic basin, supplementing the conven- tional observing network for several intensive observation periods. This unique dataset was assimilated within the framework of cycled data denial experiments for a 1-month period performed with the global model of the ECMWF. Results show a slightly reduced mean forecast error (1%–3%) over the northern Atlantic and Europe by assimilating these additional observations, with the most prominent error reductions being linked to Tropical Storm Karl, Cyclones Matthew and Nicole, and their subsequent interaction with the midlatitude waveguide. The evaluation of Forecast Sensitivity to Observation Impact (FSOI) indicates that the largest impact is due to dropsondes near tropical storms and cyclones, followed by dropsondes over the northern Atlantic and additional Canadian radiosondes. -
A Survey of Indoor Localization Systems and Technologies Faheem Zafari, Student Member, IEEE, Athanasios Gkelias, Senior Member, IEEE, Kin K
1 A Survey of Indoor Localization Systems and Technologies Faheem Zafari, Student Member, IEEE, Athanasios Gkelias, Senior Member, IEEE, Kin K. Leung, Fellow, IEEE Abstract—Indoor localization has recently witnessed an in- cities [5], smart buildings [6], smart grids [7]) and Machine crease in interest, due to the potential wide range of services it Type Communication (MTC) [8]. can provide by leveraging Internet of Things (IoT), and ubiqui- IoT is an amalgamation of numerous heterogeneous tech- tous connectivity. Different techniques, wireless technologies and mechanisms have been proposed in the literature to provide nologies and communication standards that intend to provide indoor localization services in order to improve the services end-to-end connectivity to billions of devices. Although cur- provided to the users. However, there is a lack of an up- rently the research and commercial spotlight is on emerging to-date survey paper that incorporates some of the recently technologies related to the long-range machine-to-machine proposed accurate and reliable localization systems. In this communications, existing short- and medium-range technolo- paper, we aim to provide a detailed survey of different indoor localization techniques such as Angle of Arrival (AoA), Time of gies, such as Bluetooth, Zigbee, WiFi, UWB, etc., will remain Flight (ToF), Return Time of Flight (RTOF), Received Signal inextricable parts of the IoT network umbrella. While long- Strength (RSS); based on technologies such as WiFi, Radio range IoT technologies aim to provide high coverage and low Frequency Identification Device (RFID), Ultra Wideband (UWB), power communication solution, they are incapable to support Bluetooth and systems that have been proposed in the literature. -
Launching of New RS90-AG Radiosonde Valuable
40813_VaisalaNews_155 7.12.2000 18:29 Sivu 1 155/2001155/2001 After Extensive Field Testing: Launching of New RS90-AG Radiosonde Customer Satisfaction Survey for WOBS Customers: Valuable Customer Feedback Using Product Platforms: Next Generation of Surface Weather Software Products New ROSA Weather Station Generation: Evolution Rather Than Revolution 40813_VaisalaNews_155 7.12.2000 18:29 Sivu 2 Contents President’s Column 3 Serving Better Our Customers 4 Customer Satisfaction Survey for WOBS Customers: Valuable Customer Feedback 6 Next Generation of Surface Weather Software Products 8 Meteorological Data Management System: Aurora’s payload system was MetMan for Multi-purpose Data Collection 10 developed for high altitude dropsonde missions, for use on Compact MAWS301 Automatic Weather Station 12 low speed platforms such as Demanding Tactical Military Needs 14 Pathfinder, Altus and Perseus B. Due to funding cuts, the Vaisala Technology for the U.S. Air Force 17 dropsonde payload was not Military Exhibition EUROSATORY 2000 in France 18 permitted to be deployed and Climatological Conditions on the My Thuan Bridge 19 operated from Pathfinder. Nevertheless, Aurora tested and Major Contract from the U.S. qualified the payload for flight, National Weather Service 20 using its high altitude test Using L and S-Band Boundary Layer Radars and a chambers. Vaisala’s dropsondes were an integral part of this Millimeter-wave Doppler Radar with Vaisala MAWS: scientific experiment. Weather Observations 20 Researchers are using dropson- Royal Botanic Gardens Melbourne: des to get a more accurate pic- Fostering Plant Conservation 24 ture of hurricanes. Fire RAWS Unit on the Bircher Burned Over 26 Launching of RS90-AG Radiosonde 29 Vaisala’s MAWS301 Automatic Global Positioning System 31 Weather Station is a new gener- ation weather station especially Significant Radiosonde Order designed for applications where from Met Service Canada 32 no commercial power or com- Vaisala’s Next Generation munication networks are avail- 32 able or economically installed. -
Worldwide Availability of Maritime Medium-Frequency Radio Infrastructure for R-Mode-Supported Navigation
Journal of Marine Science and Engineering Article Worldwide Availability of Maritime Medium-Frequency Radio Infrastructure for R-Mode-Supported Navigation Paul Koch * and Stefan Gewies German Aerospace Center (DLR), Institute of Communications and Navigation, Kalkhorstweg 53, 17235 Neustrelitz, Germany; [email protected] * Correspondence: [email protected] Received: 10 January 2020; Accepted: 11 March 2020; Published: 18 March 2020 Abstract: The Ranging Mode (R-Mode), a maritime terrestrial navigation system under development, is a promising approach to increase the resilient provision of position, navigation and timing (PNT) information for bridge instruments, which rely on Global Navigation Satellite Systems (GNSS). The R-Mode utilizes existing maritime radio infrastructure such as marine radio beacons, which support maritime traffic with more reliable and accurate PNT data in areas with challenging conditions. This paper analyzes the potential service, which the R-Mode could provide to the mariner if worldwide radio beacons were upgraded to broadcast R-Mode signals. The authors assumed for this study that the R-Mode is available in the service area of the 357 operational radio beacons. The comparison with the maritime traffic, which was generated from a one-day worldwide Automatic Identification System (AIS) Class A dataset, showed that on average, 67% of ships would operate in a global R-Mode service area, 40% of ships would see at least three and 25% of ships would see at least four radio beacons at a time. This means that R-Mode would support 25% to 40% of all ships with position and 67% of all ships with PNT integrity information. -
Methods of Radio Direction Finding As an Aid to Navigation
FWD : MWB Letter 1-6 DP PA RT*«ENT OF COMMERCE Circular BUREAU OF STANDARDS No. 56 WASHINGTON (March 27, 1923.)* 4 METHODS OF RADIO DIRECTION F$JDJipG AS AN AID TO NAVIGATION; THE RELATIVE ADVANTAGES OB£&fmTING THE DIRECTION FINDER ON SHORg$tgJFcN SHIPBOARD By F. W, Dunmo:^, Associate Physicist Now that the great value of the radio direction finder as an aid to navigation is being generally recognized, consider- able importance attaches to the question whether Its proper location is on shipboard, in the hands of the navigator, or on shore. The essential part of a radio direction finding equipment or '‘radio compass'' consists of a coil of wire usually wound on a frame from four to five feet square, so mounted as to be rotatable about a vertical axis. Suitable radio receiving apparatus is connected to this coil for the reception of the radio beacon signals. The construction and operation of the direction finder have been discussed in detail in Bureau of Standards Scientific Paper No. 438, by F.A.Kolster and F.W. Dunmore, to which the reader may refer for further . informa- tion.* The present paper is concerned primarily with a com- parison of the relative advantages of the location of the •direction finder on shore and on shipboard, The two methods may be briefly described as follows; 1. Direction Finder on Shore. --This method, usually con- sists in the use of two or more radio direction finder station installations on shore, each of these compass stations being connected by wire to a controlling transmitting station.