Satellite transmissions have an important role in telephone communications, television broadcasting, computer communications, maritime navigation, and military command and control. Moreover, in many situations they may be the only possible communication set-up. Recent trends in telecommunications indicate that four major growth market/service areas are: messaging and navigation services (wirele...

The objective of this study was to identify task and vehicle factors that may affect driver situation awareness (SA) and its relationship to performance, particularly in strategic (navigation) tasks. An experiment was conducted to assess the effects of in-vehicle navigation aids and reliability on driver SA and performance in a simulated navigation task. A total of 20 participants drove a virtu...

Global Navigation Satellite System performance can be significantly enhanced by introducing inter-satellite links (ISLs) in navigation constellation. The improvement in position, velocity, and time accuracy as well as the realization of autonomous functions requires ISL distance measurement data as the original input. To build a high-performance ISL, the ranging consistency among navigation sat...

Inter-Satellite links (ISLs) will be an important technique for a global navigation satellite system (GNSS) in the future. Based on the principles of general relativity, the time transfer in an ISL is modeled and the algorithm for onboard computation is described. It is found, in general, satellites with circular orbits and identical semi-major axes can benefit inter-satellite time transfer by ...

R2CGGTTS is a software program dedicated to provide clock solutions for GNSS time transfer in the standard CGGTTS (Common GPS GLONASS Time Transfer Standard) from RINEX observation files. This paper presents the upgrade of the R2CGGTTS to include observations of the future Galileo satellites; the approach is validated using the GIOVE data. A second part of the paper presents the possibilities o...

Contemporary land-survey micro-satellites have general mass up to 100 kg and are placed on the orbit altitudes from 600 up to 800 km. For such spacecraft some principle problems on attitude determination, in-flight calibration and alignment are considered and elaborated methods are presented for their solving. We present discrete algorithms for calibration and alignment of the low cost strap-do...

In a context of the evolution of localization based on the technological progress and the implementation of GNSS such as GPS or the European Galileo project to used in outdoor environment allowing accuracy of a few meters, but for an indoor environment, the signal is deteriorated due to the obstacles, so other techniques are used. This paper provides an overview of the indoor localization techn...

“Successful introduction of the satellite navigation technology in the railway safety needs accreditation of a new mode of thinking, innovation, convincing demonstration of concept and lifting of technical and mentality barriers.” This article shows a the state of the art of the SATLOC project aiming at reporting on the baseline of the project according to the objectives, in line with the terms...

Global Positioning System (GPS) has been proved to be a powerful tool for measuring co-seismic ground displacements with an application to seismic source inversion. Whereas most of the tsunamis are triggered by large earthquakes, GPS can contribute to the tsunami early warning system (TEWS) by helping to obtain tsunami source parameters in near real-time. Toward the end of 2012, the second phas...

The use of location based services has increased significantly over the last few years. However, location information is only sparsely used as a security mechanism. One of the reasons for this is the lack of location verification techniques with global coverage. Recently, a new method for authenticating signals from Global Navigation Satellite Systems(GNSS) such as GPS or Galileo has been propo...