Antenna amplifier module, function - GF82.62-P-3105-04T

Filtering and amplifying radio frequency signals

The electrical filters of the left antenna amplifier module (A2/64) and the right antenna amplifier module (A2/65) select the required frequency bands (AM, FM, TV) from the high-frequency signals received by the rear window antennas. These filters are configured differently depending on the country (e.g. , ), because the transmitting frequencies are country-specific. The filtered frequency bands are then amplified selectively and routed via coaxial lines to the corresponding control units, e.g.:

Audio gateway control unit (N93/1)
TV tuner (A2/10)
Rear SAM control unit with fuse and relay module (N10/2)

Demodulation of radio remote central locking signals

The signals for radio remote central locking (RRCL) are demodulated by the left antenna amplifier module (A2/64) and digitized. The data prepared in this manner are sent over a separate data line to the rear SAM control unit with fuse and relay module (N10/2) and forwarded to the CAN interior (CAN-B).

During demodulation the useful signal (e.g. the radio remote central locking signal) is separated from the high frequency carrier frequency (transmission frequency).

Equipment

The functionality of the left antenna amplifier module (A2/64) corresponds to the three equipment variants for radio operation:

Audio 20 CC (radio (A2)) with AM/FM amplifier and radio remote central locking receiver
With code (525) MB Audio 50 APS radio with AM/FM amplifier with antenna diversity and radio remote central locking receiver
With code (527) Navigation module for COMAND with AM/FM amplifier with antenna diversity and radio remote central locking receiver, as well as 2 TV amplifiers

The right antenna amplifier module (A2/65) with additional TV amplifiers is also required for TV operation. With code (889) Keyless Go this module is also equipped with the required receiver.

The left antenna amplifier module (A2/64) is the receiver for AM/FM and RRCL (radio remote central locking). In vehicles with FM diversity the AM amplifier with diversity unit and the radio remote central locking receiver are installed in the same housing. The module is supplemented with a separate 2x-FM-amplifier, amplifier module 1 and the window antenna (A2/71). Television reception occurs via the right antenna amplifier module (A2/65) in combination with the amplifier module 2, window antenna (A2/72) on model 211.2.

To prevent any interference to the radio and TV frequency ranges, the antenna amplifier modules for each system are diagonally installed.