The transmission is based on the Musicam method according to MPEG-1-Audio Layer-II (MP2). The audio subcarriers are modulated using quadrature phase modulation( QPSK) with a bandwidth of 130 kHz with the two channels for stereophony. The net data rate is 192 kbit/s, which corresponds to a CD-quality transmission.
For transmission of Internet data via the ADR system, there is DISCOS, which stands for Digital Subscriber on Satellite. A data channel with a transmission rate of 9.6 kbit/s is available for radio text ( RDS), program control data and conditional access( CA).
Astra Digital Radio is transmitted via the Astra 1A to 1D satellites.