Improving signal aspect awareness of a driver advisory system over the Dutch signalling system to increase capacity

The increasing passenger demand for rail service in the Netherlands, urges the Dutch infrastructure manager (IM) ProRail to increase network capacity. Instead of building new infrastructure, ProRail promotes information and communications technology solutions which aim for a more efficient utilization of the existing infrastructure. One of the...

Precision analysis of troposphere sensing using GPS single-frequency signals

Various studies have been performed to investigate the accuracy of troposphere zenith wet delays (ZWDs) determined from GPS. Most of these studies use dual-frequency GPS data of large-scale networks with long baselines to determine the absolute ZWDs. For small-scale networks the estimability of the absolute ZWDs deteriorates due to high...

A modified carrier-to-code leveling method for retrieving ionospheric observables and detecting short-term temporal variability of receiver differential code biases

Sensing the ionosphere with the global positioning system involves two sequential tasks, namely the ionospheric observable retrieval and the ionospheric parameter estimation. A prominent source of error has long been identified as short-term variability in receiver differential code bias (rDCB). We modify the carrier-to-code leveling (CCL), a...

On Evaluating Floating Car Data Quality for Knowledge Discovery

Floating car data (FCD) denotes the type of data (location, speed, and destination) produced and broadcasted periodically by running vehicles. Increasingly, intelligent transportation systems take advantage of such data for prediction purposes as input to road and transit control and to discover useful mobility patterns with applications to...

Lane Determination with GPS Precise Point Positioning

Modern intelligent transport solutions can achieve an improvement of traffic flow on motorways. With lane-specific measurements and lane-specific control, more measures are possible. Single frequency precise point positioning (PPP) is a newly developed and affordable technique to achieve an improved position accuracy compared with global...

On User Algorithms for GNSS Precise Point Positioning

Precise Point Positioning (PPP) is a Global Navigation Satellite System (GNSS) processing method with the objective of providing high positioning accuracy without the need for a nearby base station or dense network of reference stations operated by the user. To reach this objective, PPP uses the very precise carrier phase measurements in...

Publications 1998 Delft Geodetic Computing Centre

Attitude estimation for low-cost spacecraft equipped with GPS

The objective of the present paper is to give an overview of spacecraft attitude determination with GPS. GPS receivers with single or multiple antennas nowadays are low-cost sensors that constitute a valuable complement to existing sensor suites. GPS has been widely used for positioning and vehicle navigation. However, using GPS as an attitude...

Linear prediction for narrow-band interference cancellation in digital Global Positioning System receivers

Radio Frequency Interference can easily degrade the performance of the Global Positioning System (GPS), a satellite based navigation system. In order to use the GPS as a landing system in commercial aviation, GPS receivers should be protected from the harmful effects of interference. This project has proposed an interference cancellation...

A position reference system for flight test, based on GPS/IRS integration

Nowadays, several flight test organizations recognize the potential of the Navstar Global Positioning System (GPS) for flight test trajectorydetermination. In 1990 the National Aerospace Laboratory of the Netherlands (NLR) started the development of a Position Reference System (PRS) based on an Inertial Reference System (IRS), updated by GPS...

Investigations on the use of GPS for geodetic and orbit determination applications

Experiences with two GPS SPS receivers in northern Europe

Results are given of measurements with two hand-held GPS C/A- code SPS (Standard Positioning Service) receivers at thirty locations in Finland, Norway and Sweden. Comparison is made between computed positions by the receivers and positions on geographic maps. It is concluded that both receivers have pros en cons. A combination of the...

A positioning system based on NAVSAT

A worldwide navigation system called NAVSAT is discussed. This positioning system is based on satellites which broadcast information which can be used by receivers of this Information to estimate their position. The motion of the users is modelled by splines. The estimation procedure is based on the extended Kalman filter approach.

Theoretical and computational aspects of adaptively controlled Navstar antennas