Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 21 for “"HF Radar"”.
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HF Radar Observations of Inter-Annual variations in Mid-Latitude Mesospheric Winds
… study, we have used the mid-latitude SuperDARN HF radar at Saskatoon (52.16 N, -106.53 E) to study inter-annual variation in mesospheric winds. The specific aim was to determine whether or not a Quasi Biennial signature could be identified in the Saskatoon mesosphere, and if so, to understand …
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Influence of Plasma Trails from Hypersonic Events on HF Radar Data Capture
… cause atmospheric disturbances. The SuperDARN HF radar is designed to measure the ionosphere, typically to create hemisphere wide maps of ionospheric plasma convection, but meteor events are attributed to noise experienced in its data. This thesis first brings together plasma physics …
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Testing the Re-designed SuperDARN HF Radar and Modeling of a Twin Terminated Folded Dipole Array
The Super Dual Auroral Radar Network (SuperDARN) is an international collaboration of researchers interested in Earth's near-space plasma environment. This group uses high frequency (HF) radars and backscatter from magnetic field-aligned plasma irregularities to study space weather manifested in …
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Ray Tracing Analysis for the mid-latitude SuperDARN HF radar at Blackstone incorporating the IRI-2007 model
The Super Dual Auroral Radar Network (SuperDARN) is an international network of high frequency (HF) coherent scatter radars, employed to detect backscatter from magnetic field aligned plasma irregularities in the ionosphere and to study the near- Earth space weather. Space weather impacts many …
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High frequency surface wave radar demonstrator
High Frequency Surface Wave Radar (HFSWR) is used around the globe for the mapping of sea currents and coastal monitoring of the Exclusive Economic Zone. Decision to build an HF radar at the University of Cape Town (UCT) was made by Daniel O’Hagan and Andrew Wilkinson in February 2015 immediately …
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Calibration of a SuperDARN Radar Antenna by means of a Satellite Beacon
… facilitate the reception of the high frequency (HF) beacon signal from the 1 U CubeSat ZACUBE 1 by the SuperDARN HF radar in Antarctica, and by the HF direction-finding (DF) systems in both Pretoria and Hermanus. The primary objective of the HF beacon on ZACUBE 1 is to provide a continuous radio …
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Simultaneous multi-angle measurements of plasma turblence at HAARP
… recent series of experiments employing the HAARP HF transmitter to generate and study strong Langmuir turbulence (SLT) in the interaction region of overdense ionospheric plasma. Diagnostics included the Modular UHF Ionospheric Radar (MUIR) sited at HAARP, the Super DARN-Kodiak HF radar, and HF …
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Studies of aspect angle dependence of plasma turbulence at HAARP
… a recent series of campaigns employing the HAARP HF transmitter to generate and study strong Langmuir turbulence (SLT) in the interaction region of overdense ionospheric plasma. Diagnostics included the Modular UHF Ionospheric Radar (MUIR) sited at HAARP, the Super DARN-Kodiak HF radar, and HF …
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Evolution of diurnal surface winds and surface currents for Monterey Bay
… surface current observations from two CODAR (HF radar) sites are used to explore the ocean's response to diurnal-period forcing. An average diurnal cycle is formed at each wind station and at all CODAR bins. The earliest sea breeze response is seen at the coastal wind stations where morning …
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Implementation of the Transmitting Functionality on the TIGER-3 FPGA-based Transceiver Platform
High Frequency (HF) radio waves (3-30 MHz) are commonly used in long-range communication applications or in radars that require long-range detection capabilities. This is due to the refraction of HF radio waves, where the transmitted wave bends back towards to the Earth. HF radio waves can …
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Energy deposition in the lower auroral ionosphere through energetic particle precipitation
… are used in conjunction with ionospheric radars and satellite instruments to investigate high-energy precipitation in the auroral zone. There are two dominant precipitation regimes in the auroral zone which lead to enhanced high frequency radio absorption; high energy electrons (> keV) …
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Detecting and analyzing coherent structures in two-dimensional dynamical systems
… surface velocity measurements via systems like HF radar stations. An untapped resource is the data collected from float trajectories. With the goal of eventual application to these data sets, we develop a coherent structure detection algorithm utilizing sparse trajectory data. This new approach …
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Ionospheric Disturbances: Midlatitude Pi2 Magnetospheric ULF Pulsations and Medium Scale Traveling Ionospheric Disturbances
… dissertation research utilizes high frequency (HF) radio remote sensing techniques to study three distinct types of ionospheric disturbances. First, ground magnetometers and a new mid latitude SuperDARN HF radar at Blackstone, Virginia are used to observe magnetospheric Pi2 ultra low frequency …
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Morphology and dynamics of storm-time ionospheric density structures
… airglow imagers (ASIs), and Super Dual Auroral Radar Network (SuperDARN) HF radar backscatter. Simultaneous measurements from these data sets allow for continuous tracking of patch location, horizontal extent, and velocity even under adverse observational conditions for one or more of the …
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Characterization and Modeling of Solar Flare Effects in the Ionosphere Observed by HF Instruments
… role in trans-ionospheric high frequency (HF, 3-30 MHz) radiowave propagation. Solar activities, such as solar flares, radiation storms, coronal mass ejections (CMEs), alter the state of the ionosphere, a phenomenon known as Sudden Ionospheric Disturbance (SID), that can severely disrupt HF …
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Antenna systems research
… - Transmission lines and baluns, - High Radar Cross Section Reflectors for Spaceborne Radar Calibration, - Miscellaneous Antenna Investigations. These investigations have resulted in various outcomes: in new antenna types and in improved antenna configurations; in improved techniques for …
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Design of Software Defined Radio for SuperDARN Radar
… Recently, SDR has been incorporated into radar systems, particularly for ionospheric research. This study investigated the benefits and design of a high frequency (HF) SDR receiver for the next generation of Super Dual Auroral Network (SuperDARN) radars. This work analyzed digital …
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Reverse Convection Potential Saturation in the Polar Ionosphere
The results of an investigation of the reverse convection potentials in the day side high latitude ionosphere during periods of steady northward interplanetary magnetic field (IMF) are reported. While it has been shown that the polar cap potential in the ionosphere exhibits non-linear saturation …
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The Mid-Latitude Ionosphere: Modeling and Analysis of Plasma Wave Irregularities and the Potential Impact on GPS Signals
… observed by the Super Dual Auroral Radar Network (SuperDARN). In the context of this dissertation, we focus on investigating the plasma waves responsible for the mid-latitude ionospheric irregularities and studying their influence on Global Positioning System (GPS) scintillations. …
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Characterising Spatial and Temporal Ionospheric Variability with a Network of Oblique Angle-of-arrival and Doppler Ionosondes
… high frequency radio waves, to the detriment of radar and communication systems. In order to better understand the electron density structures associated with such variability at mid-latitudes, a network of oblique angle-of-arrival (AoA) and Doppler ionosondes were installed in central and …
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