Leica released an enhancement for the GS50 family of GIS/GPS receivers of an optional real-time satellite (RTS) differential module that provides submeter positioning accuracy. The RTS package consists of a small lightweight satellite receiver that mounts directly on the side of the main GS50 unit, and a combined GPS/DGPS antenna unit. The Leica RTS module works with the Racal LandStar system, a satellite-based positioning service that transmits differential GPS corrections via geostationary satellites. (Leica Geosystems, Norcross, Ga.)