The SDAR antenna (A2/82) receives signals from satellites and is also able to receive (with a special antenna on the ground) these signals from earth-bound fill-in transmitters (usually in cities). The signals received by the SDAR antenna (A2/82) are relayed over a coaxial cable to the SDAR control unit (N87/5). The SDAR control unit (N87/5) receives and decodes the signals. These signals are then transmitted over the digital data bus (D2B) to the COMAND operating, display and control unit (A40/3). This function can be activated with the "SAT" button.
The Sirius satellite-radio receiver is planned to be available as a dealer-installed option for USA version vehicles. These vehicles will be pre-wired at the factory for this service. The SDAR control unit (N87/5) and the SDAR antenna (A2/82) will then have to be installed by the dealer.