An OTDR
An optical time-domain reflectometer, often truncated to OTDR, is a measurement tool for measuring fiber optic (cables). An OTDR is often used to check whether a fiber optic range operates within the predefined requirements. Also, it is a useful tool for determining a fiber breakage where a malfunction occurred.
The OTDR is connected to the fiber optic connection to be measured. When the measurement begins, a short light pulse is sent to the fiber. This light pulse moves through the fiberglass. The reflection of the light that occurs in the fiber through contaminants in the glass travels backwards through the fiber to the OTDR. The optical level of this signal is measured and deposited against the time needed to go through the fiber. In this way, it is possible to generate a graph that includes the damping (decrease of the power of the light) of the fiber as a function of the distance.
Welding, joints and other features of a fiber optic range can be recognized by a glass fiber specialist in this graph. In this manner, fiber optic networks can be measured for delivery or malfunctions are located.
The output of the output light pulse is much higher than the return signal. Often, therefore, a bias reel: a glass fiber cable of several hundred meters, between the meter and the fiber optic. This prevents the first part of the trajectory from being measured. Also see Externe link
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