DECrepeater 90FS Installation and Configuration
63
Fiber-Optic Loss Budget
This section describes the calculated fiber-optic loss budget for the
DECrepeater 90FS.
Note the labeling on the fiber-optic cable that is being installed with the
DECrepeater 90FS. Cables are tagged according to fiber type (for example, 50/125-,
62.5/125-, 85/125-, or 100/140-micron fiber) and the attenuation of each cable is also
characterized and recorded.
10BaseFL Loss Budget
Table 5 shows the calculated loss budget for 10BaseFL fiber-optic segments used to
interconnect the DECrepeater 90FS with the cable plant. These measurements
account for the connectors at either end of the segment and are calculated using the
transmit and receive optical power levels in decibels of optical power referenced to
one milliwatt (dBm).
NOTE:
When connecting the cables to other devices, take into
account the transmit and receive optical power levels
of the other devices.
Table 5 10BaseFL Worst-Case Loss Budget (0
o
C to 50
o
C, End of Life
1
)
Unit of
Multimode, Graded Index Fiber Size
(Microns)
Measurement
Measure
50/125
62.5/125
85/125
100/140
Numerical aperture
NA
0.2
0.275
0.26
0.3
Minimum average
transmit power (P
T(avg)
)
dBm
–22.8
–19.0
–16.8
–13.5
Minimum average
receive sensitivity
(P
R(avg)
)
dBm
–32.5
–32.5
–32.5
–32.5
10BaseFL loss budget
(P
T(avg)
– P
R(avg)
)
dB
9.7
13.5
15.7
19.0
1
No additional degradation is used. It is included in the vendor’s specified power
calculations.
NOTE:
To ensure accurate measurements, do not measure
optical power levels from cables connected to ports that
are operating as responders in a redundant-link
configuration. (Refer to the section titled Redundant
Fiber-Optic Link Configuration.)
Содержание DECrepeater 90FS
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