A Multi-Constellations Satellite Selection Algorithm for Integrated Global Navigation Satellite Systems

The U.S. Global Positioning System (GPS) is currently the only fully operational global navigation satellite system (GNSS) that has been widely utilized in navigation and data collection, among other applications. In the near future, there will be other GNSSs such as the Russian GLONASS, the European Galileo, and the Chinese Compass that provide compatible services with GPS and will be available to all users. Besides operating in the single GNSS mode, future GNSS receivers will have the capability to operate in an integrated GNSS mode where they will be able to couple satellites from all available constellations for positioning solutions. However, tracking all visible satellites simultaneously increases the computational load of the receivers. This is particularly true with low-cost and compact receivers, which have limited computational resources and are commonly used in real-time intelligent transportation system (ITS) applications such as automatic vehicle location, route guidance, fleet management, vehicle dispatch, traveler information, and car navigation. These real-time applications also impose time constraints on positional updates (maximum required time interval between two epochs) while requiring high accuracy positioning solutions. To mitigate such burdens while maintaining benefits of the combined system, this article presents a new heuristic algorithm called a multi-constellations satellite selection algorithm (MCSSA). The algorithm allows an integrated GNSS receiver to track only a smaller set of visible satellites that can provide acceptable positioning solutions in the required time intervals. The MCSSA considers the geometric arrangements of visible satellites and selects the ones that spread evenly over the observed sky view. The performance of the MCSSA was validated by simulating the combined GPS and Galileo constellations. The accuracy and computation time of the MCSSA were compared with selected existing satellite selection algorithms. The results indicate that the MCSSA provides the set of satellites with near-optimal geometries giving high positional accuracy in a reasonably small computation time and thus is suitable for real-time applications.

Language

  • English

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 01140678
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Sep 16 2009 10:30AM