User's Manual

ADCP-75-198 • Issue 1 • October 2005
Page 9
© 2005, ADC Telecommunications, Inc.
3.3 Optical Cabling
3.3.1 Optical Options and Requirements
Each SDR PCIx Host Card and its associated remote (radio head) unit is connected over a pair of
optical fibers. One fiber transports the forward path optical signal and the other fiber transports the
reverse path optical signal. When diversity is used a third fiber is connected to the REV DIV port. 9/
125 single-mode optical fiber is used for the optical transport connection. With 9/125 single-mode
fiber, the optical path may be up to 10 kilometers in length. Optical fibers must be terminated with
duplex LC connectors for connection with the SDR card. Remote unit has SC connectors.
The maximum length of the optical links is dependent on the loss specifications of the optical
fiber and the losses imposed by the various connectors and splices. The system provides an
optical budget of 20dB (typical) when used with 9/125 single-mode fiber.
Whenever possible, use conduit or a guideway to route optical fibers between the SDR PCIx
Host card and the remote (radio head) unit. Avoid routing optical fibers through ladder type
cable racks or troughs that do not provide sufficient support to limit bending or prevent
accidental damage. Tie-wrapping is not recommended as a means of securing fiber optic cables.
Provide sufficient slack at each unit for connecting each fiber to the required port. Fibers may be
pre-terminated or terminated on-site using field-installable LC type connectors.
3.3.2 Optical Connections
The optical interface between the SDR PCIx Host card and the remote (radio head) unit is
supported by two optical ports. Each of the SDR PCIx Host card optical ports provides a duplex
LC-type optical transceiver which is mounted on the SDR PCIx Host card front. The remote
(radio head) unit has SC connectors.
The FWD and REV ports provide forward and reverse optical communications channels in a
non-diversity system. The REV DIV port provides receive optics for a diversity system See
Table 1 for transceiver port designations. See Figure 3 for port designations.
Note: To insure that all optical connectors and transceivers remain dust-free during
installation, leave all dust caps and dust protectors in place until directed to remove them
for connection.
Table 1. Transceiver Port Designations
DESIGNATION DIRECTION REMARKS
FWD Output Forward path (downlink) signal.
REV Input Reverse path (uplink) signal.
TEST Not used
REV DIV Input Receive optics.