Technical data

TraverseEdge 2020 Applications and Engineering Guide, Chapter 7: Optical Link Design
Page 7-12 Turin Networks Release 5.0.x
P
rmax
, are used in the link budget calculations.
P
rmin
is the lowest average optical power level at which the optical signal can be recovered
with guaranteed bit error rate of 10
-12
. This parameter is used when calculating the maxi-
mum link distance. P
rmax
is the average optical power level above which the optical
receiver is in ‘overload.’ In some situations, a span is short enough (low enough loss) that
additional attenuation is required to bring the average optical power below P
rmax
.
Connector Loss (L
c
)
Each mechanical optical connection is accomplished using one of several standard connector types
(e.g., SC, LC, FC). While some connectors are ‘better’ than others, all cause degradation such as
attentuation and reflectance to optical signals passing through them. The primary parameter com-
promising span length attributable to professionally installed connectors is attentuation, also called
“Insertion Loss” (IL, expressed in dB). All such connectors are capable of incurring an IL no more
than 0.25dB.
Figure 7-1 Connector Loss
Since the loss associated with the connectors attached to the optical transmitter and receiver are
included in the optical power and receiver sensitivity parameters these connectors are not included
separately as connector loss in optical link budget calculations. A typical fiber optic span is shown
in Figure 7-1 In fiber reach calculations two connector losses (those incurred at the two LDFs) are
included (i.e., 2 x 0.25db = 0.5dB) in the fiber reach calculations.
Turin Networks offers a number of fiber jumpers to be used in conjunction with the TE-2020 prod-
uct. Table 7-14 identifies specifications and type of finish for each of the connector type offered.
All single mode fibers follow the Corning SMF-28 fiber specification, and all multi mode fibers
follow the Corning 50/125 Infinicore standard specification.
Table 7-14 Table 1 - Connector Specifications
Connector Finish Type Insertion
Loss (dB)
Return Loss
(dB)
MPO – Single Mode Angle Polish 0.75 55