[¦trak·iŋ an ¦dad·ə ¦rē‚lā ′sad·ə·‚līt ‚sis·təm] (communications) A system providing telecommunication services between low-earth-orbiting user spacecraft and user control centers; it consists of a series of geostationary spacecraft and an earth terminal located at White Sands, New Mexico. Abbreviated TDRSS.