ANNEX I CRequirements for construction, testing, installation, and inspection
Appendix 12
POSITIONING BASED ON GLOBAL NAVIGATION SATELLITE SYSTEM (GNSS)
3.NMEA SENTENCES
F1GNS_5The Vehicle Unit shall store in the VU database the position information for latitude and longitude with a resolution of 1/10 of minute or 1/600 of a degree as described in Appendix 1 for type GeoCoordinates.
The GPS DOP and active satellites (GSA) command can be used by the VU to determine and record the signal availability and accuracy. In particular the HDOP is used to provide an indication on the level of accuracy of the recorded location data (see 4.2.2). The VU will store the value of the Horizontal Dilution of Precision (HDOP) calculated as the minimum of the HDOP values collected on the available GNSS systems.
The GNSS Id. indicates the corresponding NMEA Id. for every GNSS constellation and Satellite-Based Augmentation System (SBAS).
