Ericsson RX1290, Reference Manual

Page: 121 / 176

Technical Specification
B.2 Audio Decoding and Output Stage
B.2.1 General
•
The Multi-Format Receiver is capable of simultaneously decoding four PES
streams of audio from the transport stream. Each of the decoders is identical in
operation, but act completely independently of the other.
•
Each channel supports extraction of four types of coded audio from the
Transport Stream as follows:
•
MPEG-1, Layer 2 Audio (Musicam): ISO/IEC 13818-3
•
Dolby Digital AC-3 Audio: ATSC document A/52
•
Linear Audio: SMPTE 302M – 2000
•
DTS Audio pass-through
•
AAC
•
HE-AAC
•
Dolby E pass-through
Audio component selection is automatic or may be specified from the User Interface
or remote interfaces. The Multi-Format Receiver automatically detects the audio
type of the selected audio component and applies the appropriate algorithm. Audio
component selection is based on the position of the component descriptor in the
PMT. Audio 1 takes the first component, Audio 2 the second, Audio 3 the third and
Audio 4 the fourth. These may be overridden by selecting User-specified component
PIDs.
B.2.2 MPEG Audio
The Multi-Format Receiver supports decoding of MPEG audio as follows:
•
Compression layers: MPEG-1 layers I and II
•
Sampling rate (kHz): 48
•
Maximum compressed data rate: 384 kbps (layer II)
B.2.3 Dolby Digital AC-3 Audio
The Multi-Format Receiver is able to decode and output the primary stereo pair of a
Dolby Digital AC-3 encoded audio stream. When there is data encoded on the audio
surround channels, the Decoder applies down mixing, so that either a surround
encoded stereo pair (LtRt down mix) or a conventional stereo pair (LoRo down mix)
is available at the output.
EN/LZT 790 0003/2 R1A B-7