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 13 of 13 for “"Radio occultation"”.
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Using a co-located GNSS radio occultation payload for microwave radiometer calibration
… an orbital cross-track scanning microwave radiometer using a co-located radio occultation (RO) instrument with Global Navigation Satellite Systems (GNSS). The radiometer and RO receiver periodically observe the same volume of atmosphere near the earth's limb, allowing for overlapping, or …
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Rotational Transformation Methods for Radio Occultation and Passive Microwave Radiometry Colocation Analysis
Global Navigation Satellite System Radio Occultation (GNSS-RO) and passive microwave radiometry (MWR) provide useful atmospheric profiles for inputs into Numerical Weather Prediction models. However, both remote sensing techniques face unique challenges that require auxiliary atmospheric data to …
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Variations Of E-Region Total Electron Content And Electron Density Profiles Over High Latitudes During Winter Solstice 2007 Using Radio Occultation Measurements
… 80-150 km above the surface of the Earth, using radio occultation measurements obtained by COSMIC satellites and using Ionospheric Data Assimilation Four-Dimensional algorithm (IDA4D) which is used to mitigate the effects of F-region in the E-region estimation (Bust, Garner, & Gaussiran, 2004). …
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Laboratory Measurements of the Millimeter Wavelength Opacity of Phosphine (PH3) and Ammonia (NH3) Under Simulated Conditions for the Cassini-Saturn Encounter
… for the study of planetary atmospheres is the radio occultation experiment ??method that uses radio links between Earth, and the spacecraft which passes behind the planet. The Cassini mission to Saturn, which will be conducting such experiments at Ka-band as well as S (2.3 GHz) and X (8.4 GHz) …
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SIGNAL ANALYSIS AND RADIOHOLOGRAPHIC METHODS FOR AIRBORNE RADIO OCCULTATIONS
Global Positioning System (GPS) radio occultation (RO) is an atmospheric sounding technique utilizing the change in propagation direction and delay of the GPS signal to measure refractivity, which provides information on temperature and humidity. The GPS-RO technique is now operational on several …
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Radio and Optical Techniques for Locating Equatorial Plasma Irregularities
… and scintillation (fading) of trans-ionospheric radio communication and navigation signals are well-known symptoms of depletions. This dissertation describes new techniques to combine optical and radio ionospheric remote sensing data in common formats to leverage observational strengths and …
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Millimeter-wavelength remote sensing of the atmospheric structure and composition of Venus
Microwave radiometric observations and radio occultations are capable of providing insight into the properties of the Venus atmosphere within and below layers of clouds which cover the entire planet. To interpret such observations, accurate models for the absorption of the atmospheric constituents …
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Formation of RAAN-Spread CubeSat Constellations Utilizing Onboard Low-Thrust Propulsion
… To characterize these internal gravity waves, radio occultation sampling must occur within a timeframe and distance that allows for adequate capture of the horizontal wave vector. Receivers used in radio occultation have been successfully used on CubeSats. A CubeSat constellation of satellites …
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Resource-constrained avionics design for CubeSats
… the avionics hardware design for the Microwave Radiometer Technology Acceleration (MiRaTA) 3U CubeSat, funded by the NASA Earth Science Technology Office (ESTO), as a case study for our optimization analysis. MiRaTA will demonstrate a three-band microwave radiometer and GPS radio occultation …
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Machine Learning for Improvement of Ocean Data Resolution for Weather Forecasting and Climatological Research
… forecasts. Examining satellite datasets reveals radio occultation (RO) provides the most accurate 5-25 km altitude atmospheric measurements. However, below 5 km accuracy remains insufficient over oceans versus land areas. Some recent benchmark study e.g. Patil Iiyama (2022), and Wei Guan (2022) …
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Three-dimensional water vapor retrieval using a network of scanning compact microwave radiometers
… profiles are obtained using in-situ sensors on radiosondes and remotely using lidars, GPS ground-based networks, CPS radio occultation from satellites and a relatively small number of space-borne microwave and infrared radiometers. In-situ radiosonde measurements have excellent vertical …
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Improving nanosatellite capabilities for atmospheric sounding and characterization
… of atmospheric sensors: (i) passive microwave radiometers, (ii) atmospheric occultation experiments and (iii) coronagraphic direct imaging of exoplanets. Microwave radiometers (MWR) measure brightness temperatures in multiple channels across bands centered on atmospheric absorption features. …