Radio Relay Link (RRL) for Cassini-Huygens Mission

Cassini-Huyghens target launch date is 1995. The combined Orbiter (Cassini) and Probe (Huygens) spacecraft is foreseen to arrive in proximity of Titan for 2004. Science and housekeeping data will be transmitted by the Probe to the Orbiter for transmission to ground via the Probe Data Relay Subsystem (PDRS) operating at S band. Doppler data between the two spacecraft are needed also for reconstruction of the trajectory and definition of the wind profiles encountered by the Probe in its descent on Titan. This paper discuss the architecture, the main system analysis results and the implementation aspects of such a crucial link for the success of the mission.