GNSS stands for “Global Navigation Satellite System”, and it includes all the satellite-based positioning systems currently in orbit, either fully operational or under development. The constellations that have at least one satellite currently  in orbit are (as of November 2014):

  • GPS (United States)
  • GLONASS (Russia)
  • Galileo (European Union)
  • BeiDou (China)
  • QZSS (Japan)
  • IRNSS (India)
Galileo constellation

Galileo constellation design (credit ESA-J. Huart)

GNSS positioning is based on the reception of radio-signals emitted by a constellation of artificial satellites orbiting the Earth. The system is designed to allow, in any time and place, the tridimensional positioning of objects (including moving objects). The idea is to measure the signal “flight time”, i.e. the time interval between the emission of the signal by the satellite and the reception of the same signal by the receiver.

GReD provides the decade-long experience of its researchers in the field of GNSS positioning, particularly for:

  • development of tailored GNSS positioning software
  • analysis and processing of GNSS positioning signals
  • adjustment and maintenance of regional networks of GNSS permanent stations
  • GNSS-based monitoring of infrastructures and land deformations
COMO permanent station

The GNSS permanent station on the rooftop of Politecnico di Milano – Polo Territoriale di Como