| 摘要 |
An optical time domain reflectometer (OTDR) is treated as a linear shift-invariant system modeled as a ideal resistive-capacitive network. A step pulse is applied to a fiber under test and the return optical energy from the fiber under test is converted to signal samples representative of the return optical energy. The signal samples are processed in a controller for producing step impulse stimulus signal samples corrected for the bandwidth limited system response of the optical time domain reflectometer by modeling the OTDR as an exponential linear shift-invariant system that includes the optical transmitter, optical receiver and the fiber under test. The controller takes the time derivative of the step impulse stimulus signal samples for generating signal samples representative of the impulse response for the fiber under test. Standard OTDR interrogating pulses may be used to produce signal samples representing the ideal impulse response with bandwidth correction over the region of the pulsewidth for improved event dead zone accuracy.
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