Draw block diagram of OTDR and explain its working.

Draw block diagram of OTDR and explain its working.
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1 Answer

Answer :

Block diagram of OTDR

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Working principle of OTDR:

A light pulse is launched into the fiber in the forward direction from an injection laser using either a directional coupler or a beam splitter

Beam splitter or coupler makes possible to couple the optical power impulse into the tested fiber and simultaneously to deviate the backscattered power to the optical receiver.

The backscattered light is detected using avalanche photodiode receiver. Output of photodiode receiver drivers an integrator.

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