Range and accuracy in backscatter measurements

摘要

The relationship between measurement accuracy and signal-to-noise ratio for attenuation, joint loss, link loss and fault location measurements is established for both coherent and incoherent OTDRs. For each parameter, range is defined as the maximum distance over which a minimum acceptable measurement accuracy, or corresponding minimum acceptable signal-to-noise ratio, is attained. Range, defined in this way, serves as a basis for the comparison of different OTDRs. Results are presented which verify the theory.