User Manual

DELTANODE FIBER DAS MANUAL
©DeltaNode Solutions 2012
15
Revision 12-03
Safety and Care for fibers
The laser is a Class 3b laser that produces invisible infra-red coherent light. Avoid looking
into connected fibers and receptacles. Not safe to view with optical instruments. Always
put the protection caps on not used fibers and receptacles.
Every time a fiber is disconnected and re-connected care should be taken to avoid dust to settle on the
connector or in the receptacle. Clean with a dry fiber cleaning tool before reconnecting the fiber at all
times. A single speck of dust can impact the transmission severely. Do not touch the fiber ends with your
fingers. That will leave grease on the connectors and may cause severe problems.
Functional description
The FOI has a nominal gain of 35 dB and the laser transmitter should see a maximum composite power in
of ca 0 dBm. This means that for 0 dB attenuation in the DL a maximum input of -35 dBm composite
power is recommended (when attenuators are set to 0 dBm). If the DL attenuator is set to a higher value
the maximum recommended input is adjusted accordingly.
The output power of the laser is calibrated to 3 000 µW. This can be used to check the loss over fiber in
the remote because the remote reports the received optical levels. The loss may be different in the UL
compared to the DL because of different wavelengths on the laser.
The FOI is powered from the rack backplane and communicates with Ethernet with the other modules in
the Master Unit.
The unit contains several adjustable attenuators which means that it can compensate for loss before the
FOI (e.g. in the POI) and for loss on the fiber in the uplink. There are two sets of RF ports on the FOI that
can be used to connect signals from two different strips in the POI.
The Ethernet communication between the Master Unit and the Remote Unit takes place on two
subcarriers in the FOI where the Ethernet signals are superimposed on the RF signals.