GCI Ofix GP-1000, Руководство пользователя

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Event Type
Types of event
The events on trace are all the points that the value of power loss fluctuates
abnormally. It usually contains various types of connection and bending, crack, broken
and etc. The event points marked on trace with special marks are the abnormal points in
a fiber that cause the excursion of a normal trace.
The events can be divided into Reflection-event and Non-reflection-event
Start event
The Start-Event on an OTDR trace is the initial point. Under the default setup,
Start-Event is located on the first event (usually it is a connection between the
OTDR launching port and the connector of a fiber) of a fiber. It is a Reflection-
event.
End event
The End-Event on an OTDR trace is the end point of a fiber. Under the default
setup, End-Event is located on the last event (usually it is an end face or a broken
down point of a fiber). Usually, it is a Reflection-event.
Reflection-event
The phenomenon on a trace that some power of the optical pulse is reflected
called a reflection event. Reflection-event is displayed as a peak signal on a trace.
Non-reflection-event
The phenomenon on a trace that there exists some abnormal loss in an optical
line, but no reflection occurred is called a Non-reflection-event. It is displayed as a
drop with no peak on a trace.
Event detection
OTDR launches a bunch of optical pulse into an under-test fiber, receives the
returned optical signal and starts calculating the distance from an event. The
more the distance from the event is, the longer the returning time is cost.
According to the receiving time, distance can be calculated. By detecting the trace
generated by the returned optical signal, the attributes of the fiber itself, the
connector of the fiber, adaptor in the fiber and splicing point in the fiber can be
confirmed.