A completely geometric approach for precise orbit determination (POD) of low earth orbiter (LEO) spacecraft has been devised by the authors which does not use dynamic models, but only data from the GPS receiver onboard the LEO and the International GPS Service (IGS) precise GPS ephemeris product. The strategy relies on combining the time-continuous measurement strength of the pseudorange and ca...

Figure 1 represents the paradigm of laser scanning. A paradigm as generally known focuses on the basics and ignores minor matters. The paradigm of laser scanning can be characterised in the following way: • A bundle of 3D-vectors, positioned by GPS and oriented by IMU • Active sensors Figure 2 illustrates the paradigm of Stereo-Photogrammetry and can be characterized by: • 2 directed bundles, w...

A structural monitoring project in Singapore is described in which an RTK-GPS system comprising a pair of Leica GPS receivers installed on the Republic Plaza Building (at 280m, the maximum height of any Singaporean building) will be used to generate time series of antenna positions. This system will contribute to a project of monitoring that commenced in 1995 with the installation of two pairs ...

Recently, co-seismic seismic source characterization based on GPS measurements has been completed in near- and far-field with remarkable results. However, the accuracy of the ground displacement measurement inferred from GPS phase residuals is still depending of the distribution of satellites in the sky. We test here a method, based on the double difference (DD) computations of Line of Sight (L...

A structural monitoring project in Singapore is described, in which an RTK-GPS system comprising a pair of Leica GPS receivers installed on the Republic Plaza building (at 280m, the maximum height of any Singaporean building) will be used to generate time series of antenna positions. This system will contribute to a project of monitoring that commenced in 1995 with the installation of two pairs...

Day-scale Earth's free oscillation after large earthquakes has been detected by underground instruments such as strainmeters, gravimeters and seismometers, to investigate Earth's internal structure, geodynamics, and source properties of earthquakes. Here we show that Global Positioning System (GPS) can also detect the signals of the Earth's free oscillation. A dense GPS array in Japan (GEONET) ...