Modem: 16P0274 - Furuno Felcom 250 Service Manual

11.1 Communication unit: FB-2000

11.1.2 MODEM: 16P0274

The MODEM board executes the modulation / demodulation processing (base band) and
the data encryption processing by following the FB: Fleet broadband system
communication protocol.
The I and Q signals for the modulation signals (base band) are output to the IF board, and
nd
are converted into L-Band. The receiving signals are converted into 2 IF: 1.9 MHz by the
IF board, and then are demodulated by the MODEM board.
Fig. 11.1.4 MODEM board block diagram
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