3D urban models and availability and accuracy of global navigation satellite systems
No Thumbnail Available
URL
Journal Title
Journal ISSN
Volume Title
School of Engineering |
Master's thesis
Checking the digitized thesis and permission for publishing
Instructions for the author
Instructions for the author
Authors
Date
2012
Department
Major/Subject
Kartografia ja geoinformatiikka
Mcode
Maa-123
Degree programme
Language
en
Pages
x + 48 + [15]
Series
Abstract
The aim of this thesis was to investigate if a combined constellation of global navigation satellite systems would increase the availability and accuracy of signals in urban canyons. This was done by using a 3-D data model. Achieving the aim was possible through integrating 3-D GIS with integrated GNSS. Hence the thesis has two parts. The first deals with the different GNSS and the second with 3D GIS. The method applied was Hillshade technique in ArcMap. A satellite (which could be modeled in ArcMap by taking its azimuth and elevation) was taken as an illumination source and it was checked if a particular satellite was visible from a given place or not. This was carried out for GPS, Galileo and GPS and Galileo combined. The azimuth and elevation were extracted for the complete constellations and then processed with python. MATLAB was used to compute the Geometric Dilution of Precision, which is a measure of how good the availability of signals is. The results revealed that there was a slight improvement with combined constellation of GPS and Galileo over the stand alone systems of GPS and Galileo. The conclusion was that the combined system would certainly improve the availability of signals and their accuracy; but it was also observed that it will not help pedestrians greatly. This can be supported further by the fact that the results are only based on the Geometric Dilution of Precision and many more factors are ignored which can affect the results in different ways.Description
Supervisor
Virrantaus, KirsiThesis advisor
Vermeer, MartinVerbree, Edward
Rantala, Jaakko
Keywords
GNSS, positioning, location based services, 3D GIS, urban models