The ERASMO On-Board Unit (OBU) will provide localisation estimates for the navigation of automated vehicles with the highest level of precision, integrity, and availability, by leveraging on the information received from Galileo, the European Union’s Global Satellite Navigation System (GNSS), and a combination of absolute and relative localisation methods. ERASMO makes a determined commitment in favour of the use of Galileo along with other GNSS, so the ERASMO device will be equipped with a GNSS receiver in order to receive the Positioning, Navigation and Timing (PNT) signal broadcasted by the Galileo satellites. The availability of signals is key to ensure safety & continuity of services. This is guaranteed under most driving conditions by having, at any moment in time, a direct line of sight to 6 Galileo satellites that make up the larger constellation of 30 satellites (24 operational and six spare satellites).
Galileo satellites will offer more usable satellites than other constellations, leading to more accurate/reliable positioning and timing synchronisation for end users. This is especially beneficial for navigation in urban settings where satellite signals are often blocked by tall buildings (creating so-called urban canyons) but also in tunnels or due to other type of impediments; the ERASMO solution will make the most of the higher number of Galileo satellites in view. The expected Galileo Open Service Performance is set to achieve an availability of 99.5% *, meaning that at any given day the signal must be available for 23 hours and 52.8 minutes. For the entire duration of the autonomous driving, the ERASMO algorithm will calculate PNT information by relying on Galileo as well as HD maps, an in-Vehicle Motion Detection System (VMDS) and cameras.
The GNSS Receiver will be configured to receive signals in the L1/E1 and L5/E5a bands nominally. This means that dual-frequency measurements will be available for both Galileo and GPS. Furthermore, the PPP–RTK method that combines the concepts of Precise of Point Positioning (PPP) and Real-Time Kinematic (RTK) will be also be based on Galileo and GPS (L1/E1 and L5/E5a), while it will also be possible to reconfigure it to use signals from other GNSS signals present in various bands; This will be enabled by the highly accurate Mosaic-X5 GNSS module that supports many GNSS signals:
– GPSL1CA +GPSL2PY +GPSL2C +GPSL5
– GLOL1CA +GLOL2CA +GLOL3
– GALL1BC +GALE5a +GALE5b +GALE5
– BDSB1I +BDSB2I +BDSB3I +BDSB1C +BDSB2a
ERASMO will optimise the use of Galileo signals in terms of accuracy, integrity, correction features and availability. The ERASMO OBU will allow for the possibility to hybridise GNSS data with information from multi-sensors and vehicle information to attain the best absolute localisation information possible for the highest level of safety.
#galileo #gnss #gps #autonomousdriving #safety #automotive #ppprtk
