IEC 62104-2015 pdf free download.Characteristics of DAB receivers.
4.6.2 DAB services
The audio decoder shall conform to the subset of ISOIIEC 11172-3 as defined in ETSI EN 300 401 The conformity is described ri ETSI TS 101 757. The audio decoder should Include an error concealment melhod which may be based on the scale factor-cyclic redundancy check (ScF-CRC) as defined within ETSI EN 300 401. If, for any reason, the data stream cannot be decoded, the receiver shall mute
The audio part shall be able to decode DAB bitstreams corresponding to both 24 kHz and 48 kHz sampling frequencies
It shall comply with lSOi’IEC 11172-3 and ISOIIEC 13818-3 (bit-rates above 256 kbitis are optional).
4.6.3 DAB. services
The audio decoder shall conform to the subset of ISOIIEC 14496-3 as defined in ETSI TS 102 583 including the error concealment function in Annex A. If, for any reason, the data stream cannot be decoded, the receiver shall mute.
The audio part shall be able to decode DAB. bitstreams corresponding to all sampling frequencies defined in ETSI TS 102 563.
4.7 AutomatIc switching to another ensemble
In order to allow service foflowing of a particular DAB service, the ability of an automotive DAB receiver to switch automatically to another ensemble is mandatory. Service following shall be as described in ETSI TS 103 176. Receivers shall actively decode and act upon changes to the service following information.
4.8 Response to conditional access (CAt servIces
4.8.1 General
In DAB some service components belonging to a service may be indrvidually encrypted to
make these components incomprehensible for unauthorized users,
4.8.2 R.qulrements for DAB receivers without CA capabilitIes
These receivers shall not make encrypted service components available for selection.
Special care shall be taken in the transition from unencrypted to encrypted When this occurs on one of the selected service components, the receiver shall mute the audio in the case of an audio component. A data component shall continue to be decoded depending on the capabilibes of the receiver, In all cases where the encryphon has changed, an appropriate indication shall be given.
NOTE CA capstsMle are oebonei.
4.9 Output for audio and other services
4.9.1 General
The DAB system provides both programme and data services.
Programme services are comprised of an audio primary service component and optionally additional secondary service components. Each audio service component can also contain programme associated data (PAD) which is used to convey information intimately linked to the Sound programme In terms of content and synchronization.IEC 62104 pdf download.