Enhanced GNSS Signals to Improve Galileo System Performance

Romain Desplats, Scot Gael, Laurent Lestarquit, Lionel Ries, Jean-Luc Issler, Jose-Angel Avila Rodriguez, G√ľnter Hein

The patents disclose a clever signal design that optimises the Galileo space segment and spectrum use, allowing for better measurement accuracy (noise and multipath) for high-end receivers.

  • CBOC Patent (EP1836778): Better signal performance by adding a high-frequency component to the BOC (1,1) baseline signal in the E2-L1-E1 band. Compatibility and interoperability with the future baseline GPS civilian L1C signal.
  • Alt-BOC patent (EP1570287): Allows transmission of a total of four navigation codes in the E5a and E5b bands with constant envelope modulation. This results in high efficiency for the E5A/E5B transmission chain and minimised inter-frequency bias.

This technology has been demonstrated with a number of initial satellites as part of Galileo Signal Standard Worldwide availability and is expected to be part of the European Commission’s final Galileo programme. Signals are available right away from the Galileo satellite infrastructure. This system is compatible with existing receivers and improves on high-end receiver accuracy. CBOC: uses the high-frequency component in addition to the BOC (1,1) component Alt-BOC: processes Alt-BOC as a very wideband signal.

Contact:
Gael.Scot@cnes.fr
www.cnes.fr