35
Provisioning Optical Paths
Measure the OUT port power of the FIU board at the transmit end. Record this reading as
a
.
Measure the fiber input power on the ODF side at the receive end. Record this reading as
c
.
Measure the fiber output power on the ODF side at the transmit end. Record this reading as
b
.
Measure the IN port power of the FIU board at the receive end. Record this reading as
d
.
Subtract
b
from
a
to determine the line-side fiber insertion loss for the upstream station. This insertion
loss must be less than 1 dB. If the insertion loss is greater than 1 dB, clean the fiber connectors on
section 1. If the insertion loss remains greater than 1 dB after the fiber connectors are cleaned, the
fibers on section 1 must be replaced.
Subtract d from c to determine the line-side fiber insertion loss for the downstream station. This insertion
loss must be less than 1 dB. If the insertion loss is greater than 1 dB, clean the fiber connectors on
section 2. If the insertion loss remains greater than 1 dB after the fiber connectors are cleaned, the fibers
on section 2 must be replaced.
After ensuring that the optical paths on sections 1 and 2 are functioning properly, calculate the actual line
attenuation between the two stations according to the formula Line attenuation =
a
-
d
+ 2. (In the formula,
2 indicates 2 dB, which is the insertion loss of each FIU board.) The calculated line attenuation must be
equal to or less than the line attenuation specified in the design documents. If the line attenuation is not
within the specified range, the fibers on section 3 must be replaced.
Restore all fiber and cable connections after completing steps 1 to 3. This concludes the procedure for
provisioning optical paths from west to east.
Repeat the preceding steps to provision optical paths from east to west. Ensure that the optical paths
between the existing stations are functioning properly.
Optical power meter
Fiber patch
cord
West
East
Station B
Station A
