Public defence in geoinformatics, M.Sc. Ulla Kallio

The reference frames of different space geodetic techniques (GNSS, VLBI, SLR, DORIS) are connected to each other by local ties, the vectors between the reference points of space geodetic instruments. An important role is played by geodetic stations with more than one space geodetic instrument, one of which is the Metsähovi Geodetic Research Station. Accurate local tie vectors improve the quality of global coordinate systems and are an important part, one technique, of global coordinate system integration. 

In this dissertation, two different techniques to measure and calculate the local tie vectors between the reference points of space geodetic instruments was investigated. The first technique is based on kinematic GPS, while the second is based on the precise angle and distance measurements. 

Since GPS is a central part of the measurements in this work, the variation of the phase centre of the GPS antennas during the measurements constitutes a source of uncertainty that must be taken into account. The method to validate the calibrations of GPS antennas was developed in this dissertation, and the dedicated test field for this purpose was built at Metsähovi. 

The most important results of this dissertation are the set of local tie vectors in the global ITRF2014 reference frame and up-to-date automatic methods for measuring and calculating GNSS-based and terrestrial local ties.

Opponent: Professor Krzysztof Sośnica, Wrocław University of Environmental and Life Sciences, Poland

Custos: Assistant Professor Maaria Nordman, Aalto University School of Engineering, Department of Built Environment

Contact information of the doctoral student: Ulla Kallio, ulla.kallio@maanmittauslaitos.fi

The public defence will be organised on campus (auditorium M1, Otakaari 1). 

The thesis is publicly displayed 10 days before the defence in the publication archive Aaltodoc of Aalto University. 

Electronic thesis