GF82.60-P-3020CA Digital Audio Broadcasting (DAB), Function

GF82.60-P-3020CA Digital Audio Broadcasting (DAB), Function
MODEL 207.3 /4
- with CODE (537) Digital radio

Function requirements for Digital Radio (DAB), general
^ Circuit 30g ON

Digital Radio (DAB), general
The Digital Audio Broadcasting control unit (N87/3) allows reception of stations in DAB format. DAB offers the following advantages:
- Reliable and static-free reception of radio stations
- Reception of international radio stations
- High sound quality
- Future-safe by multimedia capability
The DAB function consists of the following processes:
^ Control of the DAB functions
^ Receipt and output of the DAB signals
^ Reception-specific switchover from DAB to FM
In vehicles as of 1.7.2011 with code (512) COMAND APS with DVD changer or code (527) COMAND APS with single DVD drive (with navigation), the Digital Audio Broadcasting control unit is designed as a dual tuner. Additional information on the DAB dual tuner can be found at the end of this document.

Control of the DAB functions
The DAB functions are operated via menu guidance in the audio equipment, which can be operated via one of the following controls:
- Buttons on audio unit
- Voice control system (VCS) (with code (511) Audio 50 APS with DVD changer or code (512) COMAND APS with DVD changer or code (527) COMAND APS with single DVD drive (with navigation))
- Audio/COMAND control panel (A40/9)
- Left multifunction steering wheel button group (S110 ) and right multifunction steering wheel button group (S111)
The control signals on the buttons on the audio equipment and the selection of the voice control are processed internally by the audio equipment.
The audio equipment reads in the voice commands for the VCS via the hands-free system microphone (A67b1).
The audio equipment receives the settings for the Audio/COMAND control panel via the telematics CAN (CAN A).
The control signals of the multifunction steering wheel button groups are forwarded to the "audio unit" via the following route:
- Steering wheel electronics (N135)
- Steering LIN (LIN E1)
- Steering column tube module control unit (N80)
- Chassis CAN (CAN E)
- Instrument cluster (A1)
- Interior CAN

Receipt and output of the DAB signals
The antenna system components receive the radio signals:
- Multifunction antenna (A28/11) receives DAB-L band signals (in vehicles up to 30.11.2010)
- Model 207.3:
The FM 2 and DAB antenna amplifier (A2/19) receives DAB Band III signals via the antenna structure in the rear window
- Model 207.4:
The TV 3, FM2 and DAB Band-III antenna amplifier (A2/54) receives DAB Band III signals via the antenna structure in the windshield
The DAB signals are forwarded to the Digital Audio Broadcasting control unit using coaxial cables. In model 207.4 with code (863) Digital/analog TV Tuner, the signals from the TV 3, FM2 and DAB Band III antenna amplifier are forwarded via the TV antenna splitter (A2/89).
Data is exchanged between the Digital Audio Broadcasting control unit and the audio equipment over the media-oriented system transport (MOST).
On vehicles without code (810) Sound system, the audio signals from the audio equipment are relayed to the following speakers via direct line and output from there:
- Left door tweeter (H4/1h1)
- Left door bass speaker (H4/1h2)
- Right door tweeter (H4/2h1)
- Right door bass speaker (H4/2h2)
- Left rear tweeter (H4/3h1)
- Left rear bass speaker (H4/3h2)
- Right rear tweeter (H4/4h1)
- Right rear bass speaker (H4/4h2)
In vehicles with code (810) Sound system the audio equipment transmits the audio signals via MOST to the sound system amplifier control unit (N40/3).
The sound system amplifier control unit processes the audio signals and relays them for output via direct lines to the following speakers:
- Door tweeter
- Door bass speaker
- Rear tweeter
- Rear bass speaker
- Center instrument panel speaker (H4/27)
- Rear shelf bass speaker (H4/29)
- Left rear surround speaker (H4/54)
- Right rear surround speaker (H4/57)

Reception-specific switchover from DAB to FM
The audio unit transmits the FM station lists to the Digital Audio Broadcasting control unit. If a comparable FM station is found, it is requested by the Digital Audio Broadcasting control unit. If the DAB reception starts to deteriorate, a switch to the FM station of the audio device occurs.
On vehicles as of 1.7.2011 with code (512) COMAND APS with DVD changer or code (527) COMAND APS with single DVD drive (with navigation), the reception-specific switchover from DAB to FM is optimized through "Seamless Linking". The digital audio broadcasting control unit compensates for the time offset between the digital and analog signals so that it is virtually impossible to hear the switchover. This requires that the audio equipment send the FM signals to the MOST when the DAB mode is active. DAB dual tuner (as of 1.7.2011 with code (512) COMAND APS with DVD changer or code (527) COMAND APS with single DVD drive (with navigation))
The Digital Audio Broadcasting control unit is designed as a dual tuner and provides not only the known functions but also the following optimizations and extensions:
- Background tuner collects the names of all available stations and Ensembles for display on the Audio/COMAND display
- Display of data for electronic program index "Electronic Program Guide" in the Audio/COMAND display (e.g. broadcast times)
- Faster switchover to another Ensemble
- Almost inaudible switchover between various Ensembles with identical program (e.g. Deutschlandradio in various Ensembles nationwide)
- Support of the extended audio codecs DAB+ and Digital Multimedia Broadcasting (DMB) audio and therefore reception of programs transmitted with these codecs