MTP-200 Series User’s Manual
Shineway Technologies, Inc. - 18 -
between two media of different IOR (For example, connections of faults, connectors, or
optic fiber end). This reflection is used to locate the discontinuous points on optic fiber. The
magnitude of reflection depends on the difference between IOR and the smoothness of
boundary.
OTDR sends out a light pulse into the connected optic fiber, and receive reflections of
events and backward scattering power of pulse in time. Locus will be displayed on LCD.
The Y-axis is dB value of backward scattering power, and the X-axis is the distance.
4.2 Measurement Application of OTDR
OTDR displays power relating to distance of returning signals. This information can be used
to identify the main properties of an optic fiber chain, such as the optic transmission
characteristic of fiber, connector and etc.
Full auto trace analysis will realize the following measurement:
➢ Event location (Distance),end or rupture of optic fiber chain
➢ Attenuation coefficient of fiber
➢ Loss of a single event (e.g. one optic tie-in), or total loss from upper end to end
➢ Range of a single event like reflection of connectors (Or grade of reflection)
➢ Auto measurement of cumulative loss of a single event
➢ Events list: event type, loss, reflection and distance.
4.3 Basic Definition and Classification of Events
Events refer to any abnormal points causing attenuation or sudden change of scattering
power besides the normal scattering of optic fiber, which include all kinds of losses like
bending, connections and ruptures.
Events points displayed on LCD are abnormal points that cause traces to deviate from
straight line.
Events can be classified as reflection events and non-reflection events.
4.3.1 Reflection Events
When some pulse energy is scattered, reflection events happen. When reflection event
To Next Page
Loading...