GF82.62-P-0001RA Antenna System (ATS), Function
GF82.62-P-0001RA Antenna System (ATS), Function
- with CODE (386) Preinstallation for telephone "Handy", UPCI system
- with CODE (387) Preinstallation for telephone "Handy", UPCI system, USA/Canada
- with CODE (388) Telephone "Handy", UPCI system
- with CODE (359) TELE AID emergency call system
Preliminary remarks
The following describes the antenna systems for audio (code 750), TV (code 860), telephone (code 388), navigation, central locking (code 466) and TELE AID (Code 359).
General information
The different antennas are matched in terms of design to their specific reception and transmitting ranges. There are active and passive antennas. The antennas can be designed as transmitter, receiver or as transmitter-receiver antennas. The antennas transmit or receive, e.g. data and voice output information through conversion of electromagnetic radio waves into high-frequency electrical voltages and vice versa.
Active antennas have a DC voltage provided for the integrated amplifier. The voltage supply is set up through separate lines or by means of signal transfer over the given coaxial lines (phantom supply). The GPS antenna (A2/23) as fitted is an active antenna.
Passive antennas do not require a voltage supply. Installed passive antennas are:
^ Windshield antennas
^ Rear window antenna
^ Rear shelf antenna (A27/68)
^ telephone antenna (A2/22)
^ Emergency call backup antenna (A2/50) (USA only)
Both the passive and active antennas can be designed as transmitter/receiving antennas .
Transmitter/receiving antennas are:
^ telephone antenna (A2/22)
^ TELE AID backup antenna (A2/50) (USA only)
Receiving antennas are:
^ Windshield antennas
^ Rear window antenna
^ Rear shelf antenna (A27/68)
^ GPS antenna (A2/23)
The Keyless Go antenna system (code 889) and the antenna system for the tire pressure monitor (code 475) are described in separate documents.
Antenna system block diagram
Displayed for the following equipment:
^ COMAND APS (with navigation) (code 527)
^ Telephone "portable CTEL" UPCI system (code 388)
^ TELE AID emergency call system (code 359) (USA only)
^ Stationary heater (code 228)
Description of block diagram for antenna system
The AM signal of the rear window antenna (4) is sent over the rear window antenna amplifier module (A2/12) to the antenna switch (3). The AM signal received by the rear shelf antenna (A2/68) is also sent over the rear shelf antenna amplifier (A2/67) to the antenna switch (3). The antenna switch (3) is integrated into the rear shelf antenna amplifier A2/67.
The antenna switch (3) switches, depending on the Vario roof position, either the AM signal of the rear shelf antenna (Vario roof closed) or the AM signal of the rear shelf antenna (A2/68) (Vario roof open) to the left antenna amplifier module (A2/64).
The switching signal for the antenna switch (3) (Vario roof open or closed) comes from the RSC control unit (N52) over the CAN bus to the radio (A2) or to the COMAND operating, display and control unit (A40/3).
The antenna control line (2) of the radio (A2) or the COMAND operating, display and control unit (A40/3) is used to actuate the antenna switch (3) in the rear shelf antenna amplifier (A2/67) using a voltage depending on the roof position.
The FM and TV signals received by the windshield antenna (5) on the left-hand side are sent to the left antenna amplifier module (A2/64). The FM, TV and RRCL signals received by the windshield antenna (5) on the right-hand side are sent to the right antenna amplifier module (A2/65).
In the right antenna amplifier module (A2/65) FM, TV and RRCL signals are filtered and amplified. TV signals are sent to the COMAND operating, display and control unit (A40/3), the FM signals (FM3, FM4) to the left antenna amplifier module (A2/64).
The RRCL signal is demodulated in the right antenna amplifier module (A2/65), digitized and sent via a data output to the overhead control panel (N70).
In the left antenna amplifier module (A2/64) FM and TV signals are filtered and amplified. The TV signals are sent to the COMAND operating, display and control unit (A40/3). The strongest of the 4 FM signals (FM1 up to FM4) is selected and sent to the radio (A2) or the COMAND operating, display and control unit (A40/3). The AM signal from the antenna switch (3) is filtered and also sent to the radio (A2) or the COMAND operating, display and control unit (A40/3).
The signals received by the GPS antenna (A2/23) are sent to the COMAND operating, display and control unit (A40/3).
If an emergency call system control unit (N123/4) (USA only) is installed, an antenna splitter (A2/5) is required, which then splits the GPS signal.
The telephone antenna (A2/22) is used to transmit and receive telephone signals and signals from the stationary heater system. The signals are sent via the telephone/portable CTEL/STH radio remote control antenna splitter (A2/53) to the corresponding component (stationary heater radio remote control receiver (A6/1) or E-net compensator (A28/3)).
If an emergency call system control unit (N123/4) (USA only) is installed, then between the telephone/portable CTEL/STH radio remote control antenna splitter (A2/53) and E-net compensator (A28/3) a frequency switchover control unit (N96) is installed. In an emergency this switches the emergency call system control unit (N123/4) straight through to the telephone antenna (A2/22). If this happens, then no calls can be made.
If reception over the telephone antenna (A2/22) is poor, the signals received by the TELE AID backup antenna (A2/50) are sent to the emergency call system control unit (N123/4), the transmission path is inverted.
In vehicles without stationary heater the telephone/portable CTEL/STH radio remote control antenna splitter (A2/53) is not installed.
With modification year 2004/1 a signal received from the stationary heater radio remote control transmitter (A8/3) by the radio remote control receiver (A6/1) is acknowledged by a radio signal.
