Method and apparatus for optical time domain reflectometry (OTDR) analysis

An apparatus for testing fiber-optic cable represented by a trace, the trace including reflectance spikes and a slope, the apparatus comprising:

• means for sampling the trace thereby producing sampled values;
• means for generating a first-order derivative of the sampled values thereby producing differential values including the reflectance spikes and the slope;
• means for removing the reflectance spikes from the differential values thereby producing sloped values including the slope;
• means for removing the slope from the sloped values thereby producing filtered values;
• and
• means for identifying a discontinuity in the filtered values thereby determining a fault.

An apparatus for testing fiber-optic cable represented by a trace including reflectance spikes, the apparatus comprising:

• means for generating a first-order derivative of the trace including the reflectance spikes;
• means for removing the reflectance spikes;
• and
• means for determining a fault in response to removing the reflectance spikes.

A method of testing comprising the steps of:

• acquiring an OTDR trace signal from a fiber-optic cable, the an OTDR trace signal characterizing operation of the fiber-optic cable;
• determining a rate of change of the an OTDR trace signal;
• removing the rate of change of the OTDR trace signal;
• and
• determining a fault in the fiber-optic cable in response to removing the rate of change of the an OTDR trace signal.

An apparatus for testing comprising:

• means for acquiring an OTDR trace signal from a fiber-optic cable, the an OTDR trace signal characterizing operation of the fiber-optic cable;
• means for determining a rate of change of the an OTDR trace signal;
• means for removing the rate of change of the OTDR trace signal;
• and
• means for determining a fault in the fiber-optic cable in response to removing the rate of change of the an OTDR trace signal.