F I M - 1 0 8 F I B E R I N T E R F A C E
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CONNECTING INTERCOM STATIONS TO THE CENTRAL MATRIX
The Clear-Com FIM-108 system transmits audio and data signals from up to eight intercom units to the matrix frame
through the process illustrated in Figure 2. For the purposes of simplification, the illustration shows only one direction
of the signal flow, while in reality the opposite direction of signal flow occurs in a a similar fashion and simultaneously,
so that the system always transmits in full-duplex mode.
Figure 1: Connecting Intercom Stations to the Central Matrix
Matrix Plus intercom stations transmit
analog
audio signals and
digital
data signals to the first FIM-108 unit via
copper cable terminated with RJ-45 connectors.
The first FIM-108 unit converts the analog audio signals to digital audio signals through an analog-to-digital
converter (ADC) located on the FIM-108 unit’s main circuit board.
The first FIM-108 unit then multiplexes (combines) the digital audio signals with the already digital data signals.
The first FIM-108 unit then converts the multiplexed digital signal into an optical signal.
The first FIM-108 unit then transmits the optical signal over up to 12 miles (20 km) of fiber-optic cable (or
1,000 ft. of coaxial cable) to the second FIM-108 unit, where a similar but reverse process occurs to convert the
signal back to its original format.
The second FIM-108 unit converts the received optical signal to a digital signal.
The second FIM-108 unit then “demultiplexes” (separates) the digital signal back into its separate audio and data
signals for each intercom unit.
The second FIM-108 unit then converts the
digital
audio signals for each intercom station to
analog
audio signals
by sending the signals through a digital-to-analog converter (DAC) located on the FIM-108 unit’s main circuit
board.
The second FIM-108 unit then transmits the analog audio and digital data signals for each intercom station to
the central matrix over copper cable terminated with RJ-45 connectors.
The central matrix receives the intercom stations’ audio and data signals in the same format in which they were
originally sent by the Matrix Plus 3 intercom stations.
Second FIM-108 unit converts received optical signal to digital signal ...
then demultiplexes (separates) the digital signal into the
separate audio and data signals for each intercom unit ...
then converts the digital-audio signals to analog-audio signals ...
The central matrix receives the intercom
stations' audio and data signals exactly
as they were originally sent.
First FIM-108 unit converts intercom audio signals to digital ...
then multiplexes digital-audio and digital-data signals into one digital signal ...
then converts multiplexed digital signal into an optical signal.
FIM-108
FIM-108
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Fiber-optic cable transmits optical signal
up to 12 miles (20 km)
Intercom stations transmit
analog-audio and digital-data signals
over copper cable to the first FIM-108 unit.
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and then transmits the analog-audio and digital-data signals
for each intercom station over copper cable to the central matrix.
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