What datum is OmniSTAR on?
A. OmniSTAR VBS in North America is on the NAD83 datum and ITRF 2005 in all other OmniSTAR world areas. OmniSTAR HP and XP are in ITRF 2005, worldwide. Some GPS receivers have the capability to convert and output the Position Data in various datums. This is a choice made by Receiver Manufacturers. Check for this option and your receiver settings to be sure. The reason for keeping the VBS in NAD83 in North America, is somewhat complex. When GPS was first installed in 1984, WGS84 matched NAD83, because it was a U.S. system. However, over the years, GPS has gradually moved to the new world datum, ITRF. OmniSTAR has elected to keep its North American VBS system on the NAD83 datum to stay consistent with prior VBS survey data.
