DORIS

DORIS (Doppler Orbitography and Radiopositioning Integrated by Satellite), a dual-frequency Doppler system, is used to determine geodetic positions from analyses of data transmitted from the sites of articial satellites. Receivers are on board specialized satellites while the transmitters are on the ground. The complete set of observations is downloaded from the satellite to the ground centre for analysis.

Source: IERS Technical Note 36: Glossary (PDF, 244KB, Not barrier-free file.) of the IERS Conventions (2010)