2.The Methods
(1)Audio encoding system

・ MPEG-2 AAC (Advanced Audio Coding) and SBR (Spectral
Band Replication) have been adopted. However, SBR is optional.

・ This system satisfies the ITU-R standard, which enables high-quality multiple channeling at a low bit rate of 144kbps or so. It has been adopted by BS digital broadcasting and terrestrial digital TV broadcasting. The adoption to the DSB resulted from the consideration of cross-media communications.