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Attenuation
Chapter 3 Optical TAPs 38
rev. 1
Use this page to create your own power loss budget from Link A to
Link B if you are considering an Optical TAP with a split ratio other
than 50/50. Then use it for your Link A or Link B to the analyzer,
whichever link has the longer fiber length. Use
Table 5 on page 33 to
assist you.
Attenuation and optical cables
Optical cables also contribute to signal attenuation. As light travels
through an optical cable, some of its energy gets dispersed and
absorbed by the cable. The attenuation rate varies depending on the
cable type used.
Depending on your transmission technology, you may be required to
use a specific cable type. Examples include single-mode (for LX or
LR) and multimode (for SX or SR). Multimode cable has a larger core
diameter than single-mode cable, resulting in greater light dispersion.
Unless the cable run is extremely long, the signal attenuation for both
cable types is minor contributor to the power loss budget. However,
multimode cable does cause higher signal attenuation than single-
Network
→
Analyzer
Send Device Power
Receive Device Sensitivity -
Power Loss Budget
Number of Connectors
Connector Loss
x
Connector Loss
Fiber Length Link A (or Link B)
Fiber Loss Link A (or Link B)
x
Fiber Loss Link A (or Link B) total +
Fiber Length to Analyzer
Fiber Loss Analyzer
x
Fiber Loss Analyzer total +
Attenuation -
Power Loss Budget - Attenuation
1
1. Light power available for analyzer. Any split ratio smaller than this number is
feasible.