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Strategies for estimating atmospheric water vapour using ground-based GPS receivers in AustraliaAgustan, January 2004 (has links)
The Global Positioning System (GPS) of navigation satellites was first developed for global navigation and position determination purposes. Signals from satellites are delayed by the Earths neutral atmosphere on propagating to ground-based receivers, termed the tropospheric delay. Although an unwanted term for precise positioning, the tropospheric delay may be converted to atmospheric water vapour, which is a vital parameter for weather forecasting.This research investigates the optimum GPS processing strategy to estimate atmospheric water vapour derived from ground-based GPS receivers particularly in the Australian region. For this purpose, GPS data observations from GPS permanent stations across Australia, mainly from the Australian Regional GPS Network, will be processed using scientific GPS software in post-processed mode and near real-time mode.This research shows that by applying high accuracy GPS data processing, the tropospheric delay could be estimated precisely. The quality of GPS data processing is indicated by the station coordinates repeatability since the coordinates can gauge at least a coarse assessment of the ability of the processing method to estimate the tropospheric delay.The precipitable water can be estimated from the wet component after separating the tropospheric delay into dry and wet components. High accuracy GPS data processing is dependent on the best choice of processing strategies, and the correct application of error-correction models and a priori constraints. This research finds that the GPS- PW estimation agrees with Radiosonde-PW estimation with an average of standard deviation at 2.5mm level for post-processed strategy and 2.8mm for near real-time strategy. The standard deviation of tropospheric parameter estimates is 1.1mm for post-processed strategy and 1.5mm for near real-time strategy.
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GPS heighting : the effect of the GPS antenna phase center variation on height determinationJohnston, Gary Michael, n/a January 2000 (has links)
This thesis examines the effect on height determination of the antenna phase centre
variation of GPS user segment antennae. A discussion of the various antenna types in
common use is followed by an explanation of the problem at hand. In particular the
effect of the antenna's environment on the phase centre variation is covered more
fully, since the phase variation phenomenon itself is largely unexplained in the
engineering community to date.
A number of examples of the heighting errors caused by this phenomenon are
presented, followed by specifically designed experiments, which quantify the effect.
Finally the phase centre variation itself is modelled for a particular GPS antenna in
common use by surveyors in Australia.
The overall conclusion, arrived at by demonstration, is that the antenna phase centre
offsets and the variation model are very important for high accuracy determinations of
height.
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Gras development, approval and implementation in AustraliaEly, William Stewart, Surveying & Spatial Information Systems, Faculty of Engineering, UNSW January 2006 (has links)
This Thesis covers the development of an alternative Global Navigation Satellite System (GNSS) augmentation technology that has become known as the Ground-based Regional Augmentation System (GRAS). GNSS augmentation technologies in support of aviation have largely been developed by countries with large economies such as the USA and members of the European Union. These technologies have focussed on solutions to the specific problems of the host nations, based on the demographics, political and economic factors relevant to them. Outside these countries, the role of GNSS augmentation has largely been ignored, specifically when considering wide area augmentation utilising Satellite Based Augmentation Systems (SBAS). SBAS technologies are expensive, and cannot be justified for nations like Australia with a relatively small number of aircraft, operated in a focussed geographic area. Utilising SBAS services provided by another country introduces cultural, legal and institutional issues that are not always easily addressed. GRAS was derived to provide a cost-effective wide area augmentation capability to nations that lacked the economic ability to field SBAS technologies. This work covers the evolution of the GRAS concept, the construction and testing of the GRAS test bed and its associated test avionics, as well as the development of standards needed to support GRAS as an internationally accepted aviation standard. The major outcome from this work was the confirmation that GRAS could meet the Required Navigation Performance (RNP) standards for Approaches with Vertical Guidance Level 2 (APV-II) as well as all less demanding modes of flight. Results from numerous ground and flight tests conducted under this research program have been reviewed by the International Civil Aviation Organisation (ICAO) GNSS Panel (GNSSP), and been instrumental in the development and validation of Standards and Recommended Practices (SARPs) which promulgate how ICAO standardised systems should perform. The final component of this work describes the project management and technology approval processes needed to get an internationally standardised system into operational use, and the particular problems that a small country like Australia has in progressing these tasks on the World stage.
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GPS : Nätverks-RTK eller RTK med Fast referensstation i Vänersborgs kommunBjarneskär, Anneli, Eriksson, Eva January 2003 (has links)
No description available.
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Near real-time precise orbit determination of low earth orbit satellites using an optimal GPS triple-differencing techniqueBae, Tae-Suk, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 174-186).
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Least-squares variance component estimation : theory and GPS applications /Amiri-Simkooei, AliReza, January 2007 (has links)
Originally presented as the author's thesis (doctoral)--Delft University of Technology. / Includes bibliographical references (p. [185]-194) and index.
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GPS : Nätverks-RTK eller RTK med Fast referensstation i Vänersborgs kommunBjarneskär, Anneli, Eriksson, Eva January 2003 (has links)
No description available.
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Robust spacecraft attitude determination using global positioning system receiversMadsen, Jared Dale 11 July 2011 (has links)
Not available / text
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GPS technology to study crustal motions in the Philippine region /Silcock, David Martin. Unknown Date (has links)
Thesis (PhD)--University of South Australia, 2002.
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Gras development, approval and implementation in AustraliaEly, William Stewart, Surveying & Spatial Information Systems, Faculty of Engineering, UNSW January 2006 (has links)
This Thesis covers the development of an alternative Global Navigation Satellite System (GNSS) augmentation technology that has become known as the Ground-based Regional Augmentation System (GRAS). GNSS augmentation technologies in support of aviation have largely been developed by countries with large economies such as the USA and members of the European Union. These technologies have focussed on solutions to the specific problems of the host nations, based on the demographics, political and economic factors relevant to them. Outside these countries, the role of GNSS augmentation has largely been ignored, specifically when considering wide area augmentation utilising Satellite Based Augmentation Systems (SBAS). SBAS technologies are expensive, and cannot be justified for nations like Australia with a relatively small number of aircraft, operated in a focussed geographic area. Utilising SBAS services provided by another country introduces cultural, legal and institutional issues that are not always easily addressed. GRAS was derived to provide a cost-effective wide area augmentation capability to nations that lacked the economic ability to field SBAS technologies. This work covers the evolution of the GRAS concept, the construction and testing of the GRAS test bed and its associated test avionics, as well as the development of standards needed to support GRAS as an internationally accepted aviation standard. The major outcome from this work was the confirmation that GRAS could meet the Required Navigation Performance (RNP) standards for Approaches with Vertical Guidance Level 2 (APV-II) as well as all less demanding modes of flight. Results from numerous ground and flight tests conducted under this research program have been reviewed by the International Civil Aviation Organisation (ICAO) GNSS Panel (GNSSP), and been instrumental in the development and validation of Standards and Recommended Practices (SARPs) which promulgate how ICAO standardised systems should perform. The final component of this work describes the project management and technology approval processes needed to get an internationally standardised system into operational use, and the particular problems that a small country like Australia has in progressing these tasks on the World stage.
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